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Conversational agents (CAs) primarily adopt knowledge scaffolding (KS) or emotional scaffolding (ES) to intervene in learners' knowledge gain and emotional experience in online learning. However, the ill-defined design for KS and ES, as well as insufficient understanding of their interactive effects on learning outcomes, have hindered the advancement of CAs in theory and practice. This study proposed systematic KS and ES design principles based on Zone of Proximal Development and growth mindset theories. We investigated their individual and combined impacts on knowledge gain and emotional experience. A quasi-experiment was conducted with 128 undergraduate students divided into four groups, corresponding to four distinct CAs: a non-scaffolding control group (CG), ES, KS, and Knowledge and Emotional Scaffolding (K＆ES) CA. The results showed that K＆ES-based CA had a significant impact on knowledge gain and emotional experience, with both being slightly improved compared to CG. Besides, KS-based CA had a positive effect on knowledge gain and emotional experience, while ES-based CA only slightly improved emotional experience compared to CG. The results validated the effectiveness of the proposed ES and KS design principles. The fine-grained analysis revealed a significant correlation between the achievement positive emotion and knowledge transfer, highlighting the importance of integrating KS and ES. In conclusion, this study offers valuable theoretical, methodological, and empirical insights for utilizing CAs to optimize online learning experiences.

Kentucky bluegrass ( Poa pratensis L.), a native grass species of the Qinghai-Tibetan Plateau, is widely used for ecological restoration due to its high growth rate and strong adaptability. However, monocultures of Poa pratensis are prone to rapid degradation and low productivity, limiting their suitability for animal husbandry. To address these challenges, this study evaluated the production performance and interspecific relationships of different mixed-sown and monoculture grasslands to identify optimal cultivation strategies. Field experiments were conducted over a six-year period, with three mixed-sown treatments— Poa pratensis combined with Siberian wildrye ( Elymus sibiricus L.), Chinese fescue ( Festuca sinensis Engler ex S.L.Lu), and alkali grass ( Puccinellia tenuiflora (Griseb.) Scribn. & Merr.)—alongside their respective monocultures. LASSO regression (Least Absolute Shrinkage and Selection Operator Regression) and ROC curve analysis (Receiver Operating Characteristic Curve Analysis) were applied to identify key factors influencing production performance. The results indicated that the mixed-sown grassland of Elymus sibiricus and Poa pratensis significantly boosted forage yield by 216.88% to 323.06% in comparison with monoculture Poa pratensis . Additionally, the comprehensive evaluation index, which integrates forage yield and nutritional quality, was 16.41% higher for the Elymus sibiricus and Poa pratensis mixture than for the monoculture Poa pratensis grassland. These findings imply that the mixed-sown grassland of Elymus sibiricus and Poa pratensis effectively addresses the low productivity issue often seen in monoculture Poa pratensis grasslands. However, in terms of yield stability and interspecific compatibility, the mixed-sown grassland of Puccinellia tenuiflora and Poa pratensis demonstrated superior performance. Its relative total yield (RTY) consistently exceeded 1.0 from the third to the sixth year, reflecting higher interspecific compatibility and stable productivity over time. And the Poa pratensis and Puccinellia tenuiflora mixture showed the best performance, achieving the highest stability value of 3.12. Therefore, the combination of Poa pratensis and Puccinellia tenuiflora is recommended as the optimal strategy for achieving long-term yield stability and high productivity in cultivated grasslands.

Fires alter the stability of organic matter and promote soil erosion which threatens the fundamental coupling of soil biogeochemical cycles. Yet, how soil biogeochemistry and its environmental drivers respond to fire remain virtually unknown globally. Here, we integrate experimental observations and random forest model, and reveal significant divergence in the responses of soil biogeochemical attributes to fire, including soil carbon (C), nitrogen (N), and phosphorus (P) contents worldwide. Fire generally decreases soil C, has non-significant impacts on total N, while it increases the contents of inorganic N and P, with some effects persisting for decades. The impacts of fire are most strongly negative in cold climates, conifer forests, and under wildfires with high intensity and frequency. Our work provides evidence that fire decouples soil biogeochemistry globally and helps to identify high-priority ecosystems where critical components of soil biogeochemistry are especially unbalanced by fire, which is fundamental for the management of ecosystems in a world subjected to more severe, recurrent, and further-reaching wildfires. Wildfires are intensifying as a result of rapid climate change. By integrating experimental observations with random forest model, the authors discovered that fires decouple soil biogeochemistry worldwide, providing critical insights for ecosystem management.

SRSF2 plays a dual role, functioning both as a transcriptional regulator and a key player in alternative splicing. The absence of Srsf2 in MyoD + progenitors resulted in perinatal mortality in mice, accompanied by severe skeletal muscle defects. SRSF2 deficiency disrupts the directional migration of MyoD progenitors, causing them to disperse into both muscle and non-muscle regions. Single-cell RNA-sequencing analysis revealed significant alterations in Srsf2-deficient myoblasts, including a reduction in extracellular matrix components, diminished expression of genes involved in ameboid-type cell migration and cytoskeleton organization, mitosis irregularities, and premature differentiation. Notably, one of the targets regulated by Srsf2 is the serine/threonine kinase Aurka. Knockdown of Aurka led to reduced cell proliferation, disrupted cytoskeleton, and impaired differentiation, reflecting the effects seen with Srsf2 knockdown. Crucially, the introduction of exogenous Aurka in Srsf2 -knockdown cells markedly alleviated the differentiation defects caused by Srsf2 knockdown. Furthermore, our research unveiled the role of Srsf2 in controlling alternative splicing within genes associated with human skeletal muscle diseases, such as BIN1 , DMPK , FHL1 , and LDB3 . Specifically, the precise knockdown of the Bin1 exon17-containing variant, which is excluded following Srsf2 depletion, profoundly disrupted C2C12 cell differentiation. In summary, our study offers valuable insights into the role of SRSF2 in governing MyoD progenitors to specific muscle regions, thereby controlling their differentiation through the regulation of targeted genes and alternative splicing during skeletal muscle development.

Oat ( L.) is an important food and forage crop whose yield and quality are influenced by genotype, environmental conditions, and sowing regimes. The stay-green (SG) trait, which delays leaf senescence and maintains photosynthetic capacity, can enhance yield and forage quality; however, systematic evaluation in oat remains limited. Two genotypes-QINGYAN 3 (control, CK) and its stay-green mutant (SG)-were evaluated over two consecutive years (2023-2024) at Huangzhong, Qinghai and Yuanmou, Yunnan under contrasting eco-sowing conditions. The SG mutant was developed through field-based phenotypic selection and long-term cultivation, resulting in a stable trait. Yield, nutritional composition, forage value, and stability were evaluated. Genotype, environment, and sowing regime effects were analyzed using linear mixed models (LMM), the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), and the Analytic Hierarchy Process (AHP) . The SG genotype showed significantly higher biomass, grain yield, starch, protein, and fat contents than CK. It also had lower fiber fractions (ADF and NDF) and higher digestibility indicators, including dry matter intake (DMI), digestible dry matter (DDM), total digestible nutrients (TDN), relative feed value (RFV), and relative forage quality (RFQ). Environmental and inter-annual effects were pronounced: warm, low-latitude conditions favored higher yield, while cool, high-altitude conditions enhanced nutritional composition and forage quality. Overall, the SG genotype outperformed CK in both yield and quality, while CK exhibited slightly greater stability across environments. The SG trait combines high yield with superior quality, providing valuable germplasm for oat improvement. Selecting genotypes according to ecological zones can further enhance forage yield and quality, supporting sustainable livestock production.

Oat is a dual-purpose crop valued for both grain and forage. The stay-green (SG) trait, which delays leaf senescence and prolongs photosynthesis, has been shown to increase yield and quality in several crop species, yet its performance across diverse environments in oats remains underexplored. In this study, multi-location field trials were conducted in Ledu, Huangzhong and Haiyan, Qinghai Province, China, to comprehensively evaluate the performance of stay-green oat lines. The traits evaluated included grain yield components, nutritional quality, and seedling establishment traits. A TOPSIS (technique for order preference by similarity to an ideal solution) model, coefficient of variation (CV) and G × E (genotype × environment) visualization were used to assess adaptability, stability, and genotype × environment interactions. On average, the stay-green lines exhibited an 16.00% increase in plot yield and a 22.93% increase in thousand-grain weight compared to controls. Notable improvements were also observed in the starch (7.58% LN_SG in HZ and HY) and protein (3.58%, QY5_SG all the sites) contents, as well as multiple seedling establishment indices, with the seedling vigor indices increasing by more than 50%. Stability analysis further showed that the stay-green lines were stable in spike length, thousand-grain weight, water-soluble carbohydrates, and seed and seedling vigor. TOPSIS analysis identified ‘LN_SG’ as the top-performing and most adaptable genotype across all environments. Overall, stay-green oat lines demonstrated superior performance in grain yield, nutritional quality, and seedling establishment. These findings highlight their potential for field application and their value as parental materials in oat breeding programs enhancing environmental adaptability and stability.

Soil salinization critically impacts potato cultivation by restricting growth, yield, and tuber quality. The MAPK pathway, evolutionarily conserved in plants, modulates hormonal balance, development, and abiotic stress responses. This study investigates the functional role of StMAPK19 , a TDY-type mitogen-activated protein kinase gene, in potato salt tolerance. Phylogenetic analysis classified StMAPK19 into a TDY-motif subgroup, and subcellular localization revealed its presence in the plasma membrane, cytoplasm, and nucleus. Under NaCl stress (50, 100, and 150 mM), StMAPK19 expression was significantly upregulated in roots, stems, and leaves. Phenotypic analyses demonstrated that StMAPK19 -overexpressing (OE) plants exhibited enhanced salt tolerance, marked by improved plant height, tuber yield, and biomass (fresh/dry weights), whereas RNA interference (RNAi) knockdown lines showed reduced growth. OE plants displayed elevated antioxidant enzyme activities, such as catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), higher proline accumulation, and reduced oxidative stress markers, including hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), while RNAi lines exhibited compromised antioxidant capacity and exacerbated oxidative damage. Expression profiling revealed upregulation of stress-responsive genes ( StCAT , StSOD , StPOD , StP5CS ) in OE plants and downregulation in RNAi lines. Gas exchange measurements further indicated that OE plants maintained higher photosynthetic rates, transpiration, and stomatal conductance under salt stress compared to non-transgenic (NT) controls, whereas RNAi plants experienced significant declines. These findings demonstrate that StMAPK19 enhances salt tolerance by modulating ROS scavenging, osmoregulatory substance biosynthesis, photosynthetic efficiency, and stress-related gene expression. This study provides critical insights into the molecular mechanisms of salt tolerance in potatoes, offering potential targets for breeding resilient varieties to mitigate salinity-induced agricultural losses.

Chiral supramolecular polymers with stimuli‐responsive circularly polarized luminescence (CPL) are highly desirable for smart flexible optoelectronic devices, but remain rarely reported. Here, a simple solvent‐free supramolecular polymerization for preparing chiral polyurethanes is presented by in situ induced self‐assembly strategy, using cellulose nanocrystals (CNCs)‐based isocyanate prepolymers and macromolecular polyols as precursors, achieving precise control over polymer chain assembly with spot‐like arrangement. More importantly, by further incorporating a π‐conjugated luminescent dihydroxynaphthalene molecule, CPL‐active flexible polyurethane films with feather‐like nanostructures are constructed, which promote the ordered arrangement of CNCs‐based isocyanate segments due to the increased spatial resistance. The π─H bond network between CNCs and urethane‐linked benzene rings drives the self‐assembly, enabling higher‐level chiral amplification and enhanced fluorescence. Interestingly, the prepared chiral fluorescent polyurethanes display multimodal chiroptical stimuli responsiveness under various stimuli, such as temperature, solvent polarity, pH, and polarized light, due to the sensitivity of the π─H bond network. This work offers new insights into designing solvent‐free chiral supramolecular polymers with significant chiroptical potentials. Precise construction of the feather‐like nanostructured chiroptical polyurethanes using cellulose nanocrystals (CNCs)‐based isocyanate prepolymers with fluorescent naphthalene structures and macromolecular polyols as precursors is manifested by solvent‐free supramolecular polymerization. Furthermore, the sensitivity of the π─H bond network to various stimuli, including temperature, solvent polarity, pH, and polarized light, is applied to realize multimodal chiroptical stimuli responsiveness.

Background Suaeda salsa ( S. salsa ) is a euhalophyte with high economic value. S. salsa can produce dimorphic seeds. Brown seeds are more salt tolerant, can germinate quickly and maintain the fitness of the species under high saline conditions. Black seeds are less salt tolerant, may become part of the seed bank and germinate when soil salinity is reduced. Previous reports have mainly focused on the ecophysiological traits of seed germination and production under saline conditions in this species. However, there is no information available on the molecular characteristics of S. salsa dimorphic seeds. Results In the present study, a total of 5825 differentially expressed genes were obtained; and 4648 differentially expressed genes were annotated based on a sequence similarity search, utilizing five public databases by transcriptome analysis. The different expression of these genes may be associated with embryo development, fatty acid, osmotic regulation substances and plant hormones in brown and black seeds. Compared to black seeds, most genes may relate to embryo development, and various genes that encode fatty acid desaturase and are involved in osmotic regulation substance synthesis or transport are upregulated in brown seeds. A large number of differentially expressed genes related to plant hormones were found in brown and black seeds, and their possible roles in regulating seed dormancy/germination were discussed. Conclusions Upregulated genes involved in seed development and osmotic regulation substance accumulation may relate to bigger seed size and rapid seed germination in brown seeds, compared to black seeds. Differentially expressed genes of hormones may relate to seed dormancy/germination and the development of brown and black seeds. The transcriptome dataset will serve as a valuable resource to further understand gene expression and functional genomics in S. salsa dimorphic seeds.

Potato is sensitive to heat stress particularly during plant seedling growth. However, limited studies have characterized the expression pattern of the family genes under heat stress and lacked validation of its function in potato plants. Potato plants were cultivated at 30°C and 35°C to induce heat stress responses. qRT-PCR was carried out to characterize the expression pattern of family genes in potato plants subjected to heat stress. loss-of-function and gain-of-function plants were established. Morphological phenotypes and growth were indicated by plant height and mass. Photosynthesis and transpiration were suggested by stomatal aperture, net photosynthetic rate, transpiration rate, and stomatal conductance. Biochemical and genetic responses were indicated by enzyme activity and mRNA expression of genes encoding CAT, SOD, and POD, and contents of H O , MDA, and proline. The expression patterns of family genes were altered in response to heat stress. StGATA2 protein located in the nucleus. is implicated in regulating plant height and weight of potato plants in response to heat stresses, especially acute heat stress. over-expression promoted photosynthesis while inhibited transpiration under heat stress. overexpression induced biochemical responses of potato plant against heat stress by regulating the contents of H O , MDA and proline and the activity of CAT, SOD and POD. overexpression caused genetic responses (CAT, SOD and POD) of potato plant against heat stress. Our data indicated that could enhance the ability of potato plants to resist heat stress-induced damages, which may provide an effective strategy to engineer potato plants for better adaptability to adverse heat stress conditions.