Epoxidized natural rubber (ENR)/multi-walled carbon nanotube (MWCNT) nanocomposites incorporating the imidazolium-based ionic liquid (IL) 1-ethyl-3-methylimidazolium chloride ([EMIM][Cl]) were prepared to investigate the effects of ionic liquids on curing behavior, electrical and dielectric properties, and stress-relaxation behavior. The novelty of this work lies in correlating ionic-liquid-assisted CNT dispersion and ionic charge transport with temperature-dependent viscoelastic relaxation in a polar, bio-based rubber nanocomposite. Rheometric analysis showed that [EMIM][Cl] significantly accelerated sulfur vulcanization, reducing scorch time from 1.21 to 0.35 min and cure time from 4.43 to 3.29 min at 3 phr loading. Morphological observations revealed that low [EMIM][Cl] content suppressed MWCNT re-agglomeration, whereas higher loadings (>= 5 phr) induced micro-phase separation of IL-rich domains. Consequently, DC electrical conductivity increased from approximately 2.22 x 10(-5) S m(-1) in IL-free composites to similar to 1.19 x 10(-4) S m(-1) at [EMIM][Cl] contents above 3 phr, accompanied by increased dielectric permittivity and dielectric loss. Temperature scanning stress relaxation (TSSR) showed that the pronounced low-temperature relaxation peak (similar to 50 degrees C), associated with MWCNT agglomerate breakdown and bound-rubber desorption, was suppressed by [EMIM][Cl]. However, excessive [EMIM][Cl] loadings accelerated stress relaxation and reduced thermal network stability due to plasticization and phase separation. Overall, [EMIM][Cl] primarily acts as a dispersion modifier and mobility enhancer in ENR/MWCNT nanocomposites.
Designing cognitively accessible mathematics instruction requires ensuring that learners can equitably process, understand, and apply complex mathematical ideas. This study examines students’ cognitive load when solving geometric integral problems by analyzing intrinsic, extraneous, and germane load within the framework of Cognitive Load Theory. Using a descriptive qualitative approach, data were collected from 144 university students in mathematics-related programs at a public university in Indonesia through think-aloud protocols, written solutions, and classroom observations. The data were analyzed using NVivo-assisted thematic coding and supported by radar visualizations to strengthen analytical trustworthiness. The findings indicate that intrinsic load constituted the dominant cognitive burden, primarily arising from symbolic-visual confusion and visual-spatial difficulties when students attempted to coordinate algebraic expressions with geometric representations. Extraneous load further increased cognitive demands due to ambiguous verbal instructions, misinterpretation of symbolic cues, and excessive technical language; however, visual scaffolding and self-generated sketches were found to reduce unnecessary processing. Germane load emerged among a smaller group of students who demonstrated conceptual transfer, reflective verification, and schema integration, indicating the development of mathematical reasoning as students connected geometric structures with their corresponding integral representations. Overall, the study highlights the central role of instructional design in regulating cognitive load to support meaningful conceptual understanding and reasoning in solving visually complex mathematical problems.
This study provides an integrated evaluation of potentially toxic element (PTE) accumulation across nine dominant mangrove species at five sites representing industrial, residential, and protected settings in Pattani Bay, Thailand. Sediment risk indices, including enrichment factor (EF), geo-accumulation index (Igeo), and metal risk index (MRI), revealed spatially variable contamination, with pronounced enrichment of Pb, Ni, Cu, and Mn in impacted zones. Statistical analysis demonstrated a decoupling effect between sediment loading and plant accumulation, suggesting that metal mobility is largely governed by internal physiological constraints rather than passive uptake. While roots served as the primary sink for lithogenic elements (Fe, Cr, and Al), distinct species-specific uptake mechanisms emerged. Linear regression indicated that bioconcentration factor for shoots (BCFs) and translocation factors (TF) are strongly modulated by internal regulatory barriers. For instance, Rhizophora apiculata exhibited a restricted transport strategy for Zn; despite high baseline accumulation (TF = 4.2; BCF = 113.3), it demonstrated a strong negative linear relationship under increasing sediment loads, effectively shielding aerial tissues. Conversely, Bruguiera cylindrica and Avicennia species challenged typical stabilization paradigms. B. cylindrica effectively concentrated Cr (Slope = 3.11), while A. marina exhibited notable Cd and Pb translocation, suggesting roles as active bioaccumulators. Furthermore, Thespesia populnea accumulated exceptional Pb concentrations (reaching 61,027.1 μg kg-1 in bark), underscoring its utility as a sentinel bioindicator. Integrating these uptake profiles with sediment data provides a practical framework for targeted coastal pollution management and ecological restoration.
The rapid advancement of digital technologies has underscored the importance of Computational Thinking (CT) as a crucial feature of competency in contemporary education. However, it is still commonplace for teachers to face difficulties translating CT concepts into effective classroom practices. This study aspired to develop and implement a community-based Professional Development Program (PDP) integrating unplugged CT activities to strengthen teachers’ knowledge, instructional performance, and attitudinal readiness with regards to CT integration. Employing a mixed-method research design, the study was conducted across three stages: program design, activity package development, and implementation. The participants were 25 secondary school computer science teachers from Thailand’s three southern border provinces. Quantitative data were collected using a knowledge test and a performance assessment rubric; qualitative data were obtained from teachers’ written reflections and analyzed using thematic content analysis. The findings showed that the participating teachers scored significantly higher than the established criterion at the .05 level. Furthermore, their instructional performance exceeded the established benchmark. The qualitative findings indicated positive attitudinal responses, including increased awareness of CT in real-life contexts, greater engagement in experiential Community-Based Learning (CBL), enhanced confidence in designing unplugged activities, and a willingness to integrate CT into lesson planning. The results suggest that integrating community contexts with unplugged learning experiences can offer a practical and contextually grounded approach to supporting teachers’ professional growth and facilitating the pedagogical integration of CT in school settings.
English-language media coverage of legislative developments surrounding marriage equality has grown considerably in Southeast Asia, with Thailand emerging as a prominent case where public and political discourse has intensified in recent years. This study investigates the types of speech acts employed in English-language news headlines about marriage equality laws in Thailand and examines the communicative functions these patterns reveal about how headlines position the issue for readers. Data were collected from 174 headlines published between 2020 and 2024 across six English-language online media outlets: the Bangkok Post, The Nation, Thai PBS World, Khaosod English, Thailand Business News, and Prachatai English. Searle’s (1969) speech act taxonomy was applied alongside content analysis to classify each headline according to its dominant speech act type. The findings reveal that assertive speech acts were most prevalent (n = 106), followed by expressive (n = 34) and directive (n = 23) acts, while commissive (n = 6) and declarative (n = 5) acts occurred least frequently. These results suggest that English-language headlines predominantly serve an informational and fact-reporting function rather than a persuasive or emotionally driven one. Nevertheless, the notable presence of expressive and directive speech acts indicates that media discourse simultaneously shapes public attitudes and mobilizes social support for marriage equality. Future research could expand the corpus to include other-language headlines for cross-linguistic comparison and examine multimodal dimensions of media framing to yield a more comprehensive understanding of how marriage equality is constructed in public discourse.
