Search Results (45,289)

Reinforcement-learning-based pedestrian agents can acquire adaptive behaviors without hand-crafted motion rules, but training from scratch in each environment is computationally expensive and often environment dependent. This paper investigates a two-stage transfer-learning framework for Deep Q-Network (DQN)-based pedestrian agents and analyzes how single-agent pretraining changes subsequent learning and behavior formation in multi-agent environments. A shared Q-network is first pretrained over four single-agent source tasks using Conservative Q-Learning with adaptive source-task allocation and is then transferred as the initial network of every agent in four multi-agent target tasks. Unlike fixed curriculum training, the source tasks are not traversed in a predetermined order; instead, experience collection is reallocated according to current collision and goal-progress performance. Compared with random initialization, the transferred network improves early-stage learning in intersection, bi-flow, and bi-door environments and significantly reduces target-task training time in these three tasks. In the bottleneck environment, the improvement is limited and the reduction in target-task training time is not statistically significant. Behavioral analysis further shows that pretraining changes early exploration: in the bi-door task, transferred agents reach goal-side and door regions earlier while spending less time near walls. Post-training trajectories also reveal collision avoidance and diverse route choices. These results clarify both the benefits and limitations of single-agent pretraining for efficient and interpretable behavior acquisition in multi-agent pedestrian simulation. Full article

Extended Reality (XR) is increasingly used to support learning experiences in cultural heritage education, but how learners interact with XR content—rather than the sophistication of the underlying technology—can meaningfully shape the quality of the learning experience. This study investigates the effects of interaction structure on cultural heritage learning in XR. A HoloLens 2 XR application for Gyeongbokgung Palace was developed using three interaction conditions: Information-Presentation (Text+Image), Inquiry-Based Exploration (QA), and Assessment-Participation (Quiz). All content was pre-generated using a Large Language Model (LLM) to hold information constant across conditions, ensuring that any observed differences in user experience could be attributed to interaction structure rather than to content. Participants experienced all three interaction types in a partially counterbalanced order, and their interest, immersion, ease of use, perceived learning comprehension, intention to reuse, and perceived difficulty were assessed. The results revealed distinct strengths for each interaction structure. Quiz generated higher preference for interest and immersion, but was also rated the most cognitively demanding condition. Text+Image achieved the highest ease-of-use ratings. QA received the numerically highest preference for perceived learning comprehension, but the difference across conditions was not statistically significant, indicating that this study did not detect a reliable preference difference on this dimension. Within this single-site, single-device study, these findings indicate that interaction structure was associated with systematically different user experience profiles, even when the underlying content was held constant. The study provides design implications for structuring interaction in cultural heritage XR learning environments. Full article

Concentrated poly(vinyl alcohol) (PVA) gel-forming networks are characterized by extensive hydrogen bonding, pronounced chain entanglement, and restricted molecular diffusion, which collectively limit oxidant accessibility and impede efficient oxidative transformation. Herein, a γ-Al₂O₃-supported MnFe₂O₄ catalyst (FMA) was developed to regulate interfacial redox properties and enhance H₂O₂ activation, thereby promoting oxidative chain scission of concentrated PVA gel-forming networks. The γ-Al₂O₃ support effectively suppressed MnFe₂O₄ aggregation, leading to enhanced specific surface area and increased exposure of accessible Fe/Mn active sites. Under optimized conditions, the FMA/H₂O₂ system achieved approximately 90% PVA conversion within 120 min, together with 89.2% TOC removal and a decrease in molecular weight from 68,892 to 2063 Da, demonstrating efficient oxidative chain scission and deep mineralization. Mechanistic investigations using XPS, EPR, and radical-quenching experiments revealed that synergistic Fe/Mn redox cycling promoted H₂O₂ activation and hydroxyl radical generation, which dominated PVA chain cleavage. The catalyst exhibited excellent stability with limited metal leaching during repeated cycles. This work demonstrates that γ-Al₂O₃-mediated interfacial regulation provides an effective strategy for designing supported metal oxide catalysts toward controlled transformation of highly entangled gel-related polymer networks, providing insights into the oxidative deconstruction of PVA-based gel and hydrogel systems. Full article

This study investigated the effects of cotton-stalk-derived wood vinegar produced at different pyrolysis temperatures on nitrogen and phosphorus transformations and the associated microbial mechanisms during the aerobic composting of chicken manure. Wood vinegar produced at 300, 350, 400, 450, and 500 °C was applied in a 38-day composting experiment. Changes in physicochemical properties, nitrogen and phosphorus fractions, bacterial community succession, and potential functional profiles were analyzed using 16S rRNA gene sequencing, Spearman correlation analysis, and PICRUSt2-based COG functional prediction. The results showed that cotton-stalk-derived wood vinegar improved the composting process and regulated nutrient transformation. Compared with T0, the thermophilic phase was prolonged by 1–4 days in T1, T3, and T5. At the end of composting, the pH and electrical conductivity of all treatments ranged from 7.45 to 7.72 and from 1.37 to 1.75 mS/cm, respectively, which were within acceptable ranges for mature compost. The effects of wood vinegar on nitrogen and phosphorus transformations varied with pyrolysis temperature. All wood-vinegar-amended treatments maintained higher final TN concentrations than T0. Among them, T4 maintained a high final TN concentration of 22.90 g/kg, which was 11.17% higher than that of T0 and close to the highest value observed among all treatments. However, inorganic nitrogen responses differed among treatments: T1 showed more efficient conversion of NH₄⁺-N to NO₃⁻-N, whereas T3 had the lowest NH₄⁺-N/NO₃⁻-N ratio, indicating relatively higher compost maturity. Therefore, the nitrogen results should be interpreted on a concentration basis rather than as evidence of reactor-scale total nitrogen retention or nitrogen loss. Wood vinegar also affected phosphorus transformation, with T4 achieving a higher available phosphorus concentration. Bacterial community analysis showed that Bacillota and Actinomycetota dominated the composting process, and T4 maintained a more stable bacterial community structure during maturation. T4 was enriched in potential functional genera, including Saccharomonospora and Thermoactinomyces. Spearman correlation analysis indicated that Weissella and Pediococcus were significantly associated with nitrogen-related parameters in T4, whereas Saccharomonospora was closely linked to phosphorus transformation. PICRUSt2-based COG prediction further suggested that T4 maintained relatively stable nitrogen- and phosphorus-related functional potentials. Full article

Intravesical Bacillus Calmette–Guérin (BCG) remains the standard adjuvant treatment for intermediate- and high-risk non-muscle-invasive bladder cancer. However, 30–50% of patients fail to respond or experience recurrence within two years, while clinical and pathological risk models have limited accuracy in predicting individual response. This narrative review summarizes molecular classifications and candidate biomarkers associated with BCG response and assesses their potential clinical utility, based on a focused search of PubMed, Scopus, and Web of Science through July 2026, supplemented by ClinicalTrials.gov, regulatory documents, and current guidelines. Transcriptomic classifications, including UROMOL2021, BCG Response Subtypes (BRS), MSP888, and subtypes defined in stage T1 disease, identify tumor phenotypes associated with differences in recurrence, progression, and outcomes after BCG. BRS3 is characterized by basal-squamous and immunosuppressive features and is associated with shorter recurrence-free and progression-free survival. Genomic alterations, including FGFR3 and TERT promoter mutations and APOBEC signatures; DNA methylation markers such as GATA2, TBX3, and GPR158; and tumor microenvironment features, including regulatory T cells, exhausted CD8+ T cells, and PD-L1 expression, have been associated with outcomes in individual cohorts but remain unvalidated as treatment-specific predictors. Bladder-preserving options for BCG-unresponsive disease include pembrolizumab, nadofaragene firadenovec, nogapendekin alfa inbakicept-pmln with BCG, and the gemcitabine intravesical system. Randomized trials adding checkpoint inhibition to BCG in BCG-naive disease have reported inconsistent results. No molecular biomarker is currently validated for treatment selection. Molecular profiling remains investigational and may complement, but not replace, established clinical risk assessment. Clinical implementation requires prospective biomarker-stratified trials with standardized definitions, assays, and endpoints. Full article

Although rubric co-construction has been associated with positive outcomes in L2 writing classrooms, relatively little is known about how multilingual learners experience participation in rubric development or how collaborative interactions contribute to learning. This qualitative case study examined rubric co-construction in an undergraduate ESL writing course to investigate (1) students’ perceptions of participating in rubric development and (2) the interactional processes through which assessment criteria were negotiated. Data included classroom recordings, collaborative worksheets, rubric drafts, student reflections, semi-structured interviews, and researcher field notes, and were analyzed thematically through the lenses of democratic assessment, assessment for learning, and sociocultural theory. Findings indicate that rubric co-construction clarified expectations, strengthened students’ engagement with assessment, and increased confidence in evaluating both their own writing and that of their peers. Collaborative dialogue, negotiation of meaning, consensus building, instructor scaffolding, and the development of shared assessment criteria emerged as key mechanisms supporting assessment literacy. The findings suggest that the educational value of rubric co-construction lies not only in the resulting rubric but also in the participatory processes through which multilingual learners develop shared understandings of writing quality. Full article

In situ gasification-assisted hydrogen production from heavy oil has the potential to simultaneously achieve in-reservoir upgrading and hydrogen generation, offering a promising pathway for the clean and efficient development of heavy oil resources. To investigate stage-dependent hydrogen-formation pathways and the thermal conversion behavior of the heavy oil-water system, batch reactor experiments were conducted to simulate heavy oil gasification under reservoir-like conditions. Experiments were carried out under a nitrogen atmosphere at different temperatures and reaction times. Combined with gas chromatography and elemental analysis, the product distribution and reaction characteristics were investigated. The results show that, under an inert N₂ atmosphere with an oil-to-water mass ratio of 1:1, in situ hydrogen production from heavy oil can be qualitatively divided into three approximate stages: a deoxygenation activation stage (300–400 °C), a water–gas shift hydrogen-production stage (400–500 °C), and a coke conversion hydrogen-production stage (500–550 °C). Temperature was identified as the key factor governing the reaction pathway, and the highest H₂ mole fraction of 10.84% was obtained at 450 °C for 6 h. Reaction time mainly affected thermal conversion and gas distribution, while excessively long residence time at high temperatures promoted hydrogen-consuming reactions. Elemental analysis of the high-temperature residues further revealed enhanced dehydrogenation, aromatization, and coking, indicating that coke served as an important intermediate for sustained hydrogen generation. A stage-dependent mechanism of in situ hydrogen production from heavy oil at 300–550 °C was proposed, and the dominant reactions controlling H₂ generation in different temperature intervals were clarified. These findings provide a basis for process optimization and numerical simulation of in situ hydrogen production from heavy oil. Full article

This work reports an experimental study of the micromechanical properties of the Co₇₀Fe₃Mn_3.5Mo_1.5Si₁₁B₁₁ (at. %) amorphous alloy. All experiments were performed at room temperature on the unannealed sample in order to avoid the influence of thermally induced structural relaxation. X-ray diffraction confirmed the amorphous structure. Using nanoindentation tests, we determined key mechanical characteristics under a 20 mN load, including hardness, elastic and plastic deformation parameters, creep ratio, and other micromechanical properties. Scratch testing was performed under both static (20 mN) and dynamic (0.3–100 mN) regimes. We analyzed variations in penetration depth and residual depth during scratch testing. Surface morphology analysis after scratch testing confirmed no macroscopic crack formation or delamination. The friction coefficient behavior indicates sensitivity to localized contact loading and is consistent with localized deformation processes within the sample. A pronounced time-dependent deformation (C_IT ~ 4.7%) under localized contact loading was also observed. The data were analyzed considering the structural state of the sample’s amorphous matrix and existing theories of plastic deformation mechanisms in amorphous systems. The ratio of elastic to plastic deformation, along with time-dependent deformation (creep), enables specification of the mechanical response of the investigated amorphous ribbon under localized microcontact loading. The obtained results provide qualitative insight into the deformation characteristics of unannealed amorphous ribbons. Full article

The flotation of oxidized copper minerals is limited by poor surface reactivity and the insufficient effectiveness of conventional sulfidization. This study investigated 50 Hz alternating current electrochemical pretreatment to enhance the sulfidization and flotation of chrysocolla and a natural oxidized copper ore. Operating parameters, including current density, treatment time, pulp pH, and sodium sulfide dosage, were optimized using a design of experiments approach. Phase transformations were characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy and X-ray diffraction. Pretreatment with 50 Hz alternating current promoted the surface formation of tenorite (CuO), which was subsequently transformed into covellite (CuS) during sulfidization, providing favorable conditions for subsequent flotation. The optimum conditions for chrysocolla were a current density of 100 A m⁻², a pretreatment time of 0.5 min, pH 8, a sodium sulfide dosage of 25% of the stoichiometric requirement, and a sulfidization time of 2.5 min. Validation tests on natural oxidized copper ore showed that alternating current pretreatment increased copper recovery from 29.16% to 79.63% and concentrate grade from 12.84 to 25.50 wt.% compared with conventional sulfidization. These findings demonstrate that alternating current electrochemical pretreatment effectively modifies oxidized copper mineral surfaces and enhances their subsequent sulfidization and flotation, providing a promising approach for the beneficiation of refractory oxidized copper ores. Full article

Ambrosia artemisiifolia L. (common ragweed, Asteraceae), native to North America, is a highly invasive weed causing substantial agricultural losses and serious human health problems due to its allergenic pollen. In several countries, legal regulations require its active management. The North American leaf beetle Ophraella communa (Coleoptera: Chrysomelidae) is a biological control agent that can suppress ragweed growth and pollen production. This study evaluated the effectiveness of a synthetic herbicide, a bioherbicide, mowing, and O. communa releases at different densities and timings, applied alone or in combination under field conditions. Three field experiments were conducted in a major European hotspot of A. artemisiifolia in the Pannonian region of Hungary during the 2024 and 2025 growing seasons. Both herbicides, as well as mowing, reduced A. artemisiifolia growth and, to some extent, flower head formation, but not flowering intensity. Ophraella communa established at low densities regardless of the number and timing of released beetles, and despite the hot and dry summer climate of the region. The highest abundance and most damage were observed following medium-density early-season releases (4 beetles per m²) and high-density mid-season releases (32 beetles per m²). The results suggest that repeated or more intensive management may be required for an effective season-long suppression of A. artemisiifolia, and that early, higher-density O. communa releases under different local climates may warrant further investigation. Full article

This study examines structural heterogeneity in destination loyalty formation in a mature tourism destination by investigating whether visit frequency conditions the relationships among perceived destination attribute salience, primary travel motivations, tourist satisfaction, and destination loyalty. Using an analytical sample of 37,781 international tourists from the Canary Islands Tourist Expenditure Survey, the proposed framework was assessed through covariance-based structural equation modelling (CB-SEM) and multigroup analysis. Perceived destination attribute salience was represented by four empirically retained dimensions, whereas primary travel motivations were modelled as observed categorical exogenous variables relative to an empirical reference category. Tourist satisfaction and destination loyalty were specified as latent constructs, with loyalty capturing both intention to return and willingness to recommend. Measurement invariance analysis supported metric and partial scalar invariance across frequent and non-frequent visitors, providing a basis for comparing structural relationships between the two groups. Results show that tourist satisfaction is strongly and positively associated with destination loyalty in both groups, although the magnitude of this relationship differs significantly between them. The associations linking destination attributes and primary travel motivations to satisfaction and loyalty also vary according to previous visitation. Cross-group tests indicate significant moderation by visit frequency across all motivation–loyalty relationships and for the Natural and Cultural Experience–loyalty relationship. Moreover, indirect-effect comparisons reveal moderated mediation through tourist satisfaction for Natural and Cultural Experience, Sun and Beach, and the Fun, Family, Rest, and Exploration motivations. These findings indicate that the structural pathways associated with destination loyalty are not homogeneous across levels of previous visitation. The study contributes to destination loyalty research by jointly examining direct, mediated, and visit-frequency-conditioned relationships within a unified structural framework. From a managerial perspective, the results support differentiated strategies for frequent and non-frequent visitors while emphasizing tourist satisfaction as a central correlate of destination loyalty. Full article

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy, and gemcitabine (GEM) resistance is a major contributor to its poor clinical outcomes, generating an urgent need for novel therapeutic strategies targeting tumor proliferation and tumor-cell-intrinsic malignant signaling. This study aimed to investigate the synergistic anti-PDAC efficacy and underlying mechanism of cepharanthine (CEP) combined with GEM. A series of in vitro and in vivo experiments were performed to evaluate the antitumor activity, synergistic effect and preliminary in vivo safety of the CEP-GEM combination. Bioinformatics analysis coupled with experimental validation was applied to dissect the underlying mechanisms. The results demonstrated that CEP produced marked synergistic effects with GEM to suppress PDAC growth both in vitro and in vivo. Mechanistic investigations revealed that CEP blocked the PI3K/AKT/mTOR pathway and reduced tumor-cell-intrinsic PD-1/PD-L1 levels, thereby facilitating tumor-cell apoptosis, restraining cell migration and invasion, and sensitizing GEM-relatively insensitive AsPC-1 cells to GEM. Under our experimental conditions, no obvious histopathological injury or prominent systemic toxicity was observed. In conclusion, this work provides preclinical evidence showing that the CEP-GEM combination exerts anti-tumor activity via dual-pathway suppression in PDAC cells, and supports further translational research for PDAC. Full article

White tea is rich in polyphenols with antioxidant potential, but information on Zheng’an white tea remains limited. This study optimized water-based ultrasound-assisted extraction (UAE) using single-factor experiments and a Box–Behnken design and evaluated the antioxidant activity of the resulting extract. Tea-leaf microstructure, polyphenolic composition, and antioxidant capacity were assessed using scanning electron microscopy (SEM), liquid chromatography–mass spectrometry (LC–MS), in vitro radical-scavenging assays, and a Caenorhabditis elegans model, respectively. The optimized conditions within the investigated experimental domain were a solid-to-liquid ratio of 1:50 (g/mL), an ultrasonic time of 50 min, and an ultrasonic power of 118 W, yielding a total polyphenol content of 37.93 ± 0.17 mg GAE/g DW. SEM revealed marked disruption of tea-leaf cellular structures after UAE. LC–MS enabled the putative annotation of 25 representative polyphenols spanning phenolic acids, flavan-3-ols, procyanidins, flavonols and their glycosides, and related derivatives. At 1.5 mg/mL, the extract exhibited ABTS and DPPH radical-scavenging rates of 81.68 ± 3.23% and 85.43 ± 2.31%, respectively. In C. elegans, 100 μg/mL extract increased catalase activity by 86.03% and decreased malondialdehyde content by 46.40% (p < 0.01). These findings show that the optimized aqueous UAE procedure recovered a polyphenol-rich extract with antioxidant activity in the tested chemical assays and C. elegans model. Full article

This study investigates the effectiveness of using an interpolymer complex based on a synthetic polycation—Metacid (polyhexamethylene guanidine hydrochloride) and a natural biopolymer—chitosan for anti-erosion soil structuring in the Maktaaral district of the Turkestan region. Using the conical plastometry method, the critical concentration of structure formation in the soil suspension was determined to be 67.5%; for subsequent studies, the solid phase content was taken to be 70%. Rheological studies have revealed a pronounced synergistic effect of the combined use of Metacid and chitosan. If the initial soil–water system is characterized by low elastic moduli (E1, E2 ~ 10⁴ Pa), then the introduction of the “Metacid–chitosan” interpolymer complex leads to a sharp strengthening of the structure: The values of E1 and E2 increase to 3.26·10⁶–7.49·10⁶ Pa and 1.04·10⁶–1.46·10⁶ Pa, respectively. The mechanical stability limit increases by more than twofold, reaching 2000–2500 Pa. Analysis of the ζ-potential and electrical conductivity showed that the Metacid ensures a high positive charge of the complex (+21.76 … 28.69 mV), and chitosan acts as a spatial matrix. Experiments in a wind tunnel have confirmed that the “Metacid–chitosan” formulation, at an optimal concentration of 0.4%, provides effective protection of soil aggregates against wind erosion. The results obtained open up new prospects for using ecologically balanced interpolymer complexes to stabilize arable lands. Full article

Efficient and accurate flood risk assessment is essential for cultural heritage conservation in the context of increasingly frequent extreme weather events. Conventional flood risk assessment methods primarily aim to approximate inundation patterns across the entire study area, and their analytical units are not necessarily aligned with object-oriented decision-making. To address this limitation, this study develops a site-oriented surrogate modeling approach. The approach integrates site-specific characteristics with multi-scale neighborhood features to characterize local environmental constraints and investigates how neighborhood scale influences predictive performance. To this end, five models are constructed and compared, i.e., M1_Site, M2_50m, M3_200m, M4_500m, and M5_Multi-Scale. Experiments were conducted on 714 cultural heritage sites in Shanghai. Overall, the M2_50m, M3_200m, and M5_Multi-Scale models demonstrate strong predictive performance, with Test F1, GroupKFold F1, and Test Accuracy all above 0.85. According to the results, the site-oriented surrogate modeling approach is feasible, and neighborhood features are important. Model performances also exhibited clear scale sensitivity. This approach provides a practical framework for rapid, site-specific flood risk assessment and offers new insights for decision-making in cultural heritage conservation. Future research could focus on validating this approach in other contexts and applying it to multi-scenario risk analyses to further support heritage conservation planning. Full article