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- Tropical ecosystem shifts at the Eocene–Oligocene transition in the southwestern Caribbean regionPublication . Trejos-Tamayo, Raúl; Garzón, Darwin; Ochoa, Diana; Plata-Torres, Angelo; Frontalini, Fabrizio; Vallejo-Hincapié, Felipe; Abrantes, Fatima; Magalhães, Vitor; Arias-Villegas, Viviana; Jaramillo, Carlos; Escobar, Jaime; Curtis, Jason H.; Flores, José-Abel; Osorio-Tabares, Constanza; Duque Castaño, Monica Liliana; Bedoya, Erika; Pardo-Trujillo, AndrésThe Eocene-Oligocene transition (EOT; similar to 34 Ma) marks a pivotal climatic shift from a warm, ice-free world to a cooler, glaciated climate driven by a significant decline in atmospheric pCO2 levels. This global cooling event, characterized by the first major Antarctic glaciation and a similar to 50 m sea-level fall, triggered selective extinctions in marine ecosystems and restructured sedimentary processes, making it one of the most significant climatic events of the Cenozoic. While the global impacts of the EOT are well documented, its effects on the marine environment of NW South America remain poorly understood. This region's unique position as a connection between the Pacific and Atlantic oceans before the closure of the Central American Seaway provides a valuable window into tropical ecosystem responses during this period. This study integrates micropaleontological and geochemical data from the ANH-SJ-1 drill core in the Colombian Caribbean to evaluate the impacts of global climatic shifts on tropical marine ecosystems. Palynological indicators, including the terrestrial/marine (T/M) index, along with XRF-derived elemental ratios (Zr/Rb, Ti/Al, K/Al, and K/Rb), reflect enhanced continental input during the EOT. These patterns suggest intensified erosion and detrital transport to bathyal depths, likely driven by rapid sea-level fall and hypopycnal flows. Calcareous nannofossil trophic indices reveal elevated surface productivity, likely fueled by increased continental nutrient influx, supported by higher Ba/Ti ratios that indicate enhanced organic matter export to the seafloor. The resulting oxygen depletion favored infaunal over epifaunal benthic foraminifera, marking a shift in community structure. Improved carbonate preservation across the transition, evidenced by a shift from agglutinated to calcareous benthic foraminifera and higher Ca/Ti ratios, reflects a deepening of the carbonate compensation depth (CCD), likely due to enhanced alkalinity from continental weathering. A positive delta 13Corg excursion (similar to 0.84 parts per thousand) aligns with global records and supports contributions from organic carbon oxidation, volcanic inputs, and weathering. Although limited by the number of available samples and low fossil abundances in some intervals, our multiproxy approach enables a coherent reconstruction of environmental dynamics. The ANH-SJ-1 record highlights the sensitivity of tropical systems to global climatic shifts and reinforces the importance of tropical data for understanding Cenozoic climate evolution and anticipating future ecosystem responses.
- LINA: an augmented reality social game enhancing sense of belonging among classmates: an uncontrolled pre-post evaluation studyPublication . Krammer, Ina; Mittmann, Gloria; Nater, Urs M.; Barnard, Adam; Martins, Diogo; Dias, João; Schrank, Beate; Woodcock, Kate A.Supportive peer relationships are fundamental in the development of well-being. Since early adolescents spend a lot of time at school, especially in their classroom, a sense of belonging among classmates plays a pivotal role for mental health and academic functioning. Programs that enhance sense of belonging among classmates through improving peer relationships in classrooms are rare. Given that early adolescents increasingly use digital media to establish and maintain relationships with classmates, there is potential in digital social games that enhance social connectivity and collaboration, especially during the difficult transition from primary to secondary school. LINA ('Lina Is Not Alone') is a novel social augmented reality game for classrooms that is designed to enhance sense of belonging among classmates through improving their relationships with classmates. We conducted an uncontrolled pre-post evaluation study to evaluate (a) player experience, (b) translation of the theory-led LINA design into user experience and (c) increases in sense of belonging after engagement with LINA. In total, data from 99 participants (Mage = 10.94; range = 10-12; 51 girls, 48 boys) were included in this study. Our results provided evidence for (a) high satisfaction and acceptability of LINA, (b) a successful translation of theory-led design features into user experiences, and (c) increases in sense of belonging. We discuss practical implications and future development of LINA.
- AI-enhanced adaptive testing with cognitive diagnostic feedback and its association with performance in undergraduate surgical education: a pilot studyPublication . Gonçalves, Nuno Silva; Collares, Carlos; Pêgo, José MiguelBackground: Effective feedback in the cognitive domain is essential for surgical education but often limited by resource constraints and traditional assessment formats. Artificial Intelligence (AI) has emerged as a catalyst for innovation, enabling automated feedback, real-time cognitive diagnostics, and scalable item generation, thereby transforming how future surgeons learn and are assessed. Methods: An item bank of 150 multiple-choice questions was developed using AI-assisted item generation and difficulty estimation. A formative Computerized Adaptive Testing (CAT), balanced across three cognitive domains (memory, analysis, and decision) and surgical topics, was delivered via QuizOne® 3–5 days before the summative Progress Test. A total of 147 students participated, of whom 116 completed the formative CAT. Performance correlations, group comparisons, analysis of covariance (ANCOVA), and regression analyses were conducted. Results: Students who voluntarily completed CAT showed higher Progress Test scores, though causality cannot be established due to self-selection bias (p = 0.021), with the effect persisting after adjusting for prior academic performance (ANCOVA p = 0.041). Memory skills were the strongest predictors of summative outcomes (R2 = 0.180, β = 0.425), followed by analysis (R2 = 0.080, β = 0.283); decision was not significant (R2 = 0.029, β = 0.170). Conclusion: AI-enhanced CAT–Cognitive Diagnostic Modeling (CDM) represents a promising formative approach in undergraduate surgical education, being associated with higher summative performance and providing individualized diagnostic feedback. Refining feedback presentation and enhancing decisionmaking assessment could further optimize its educational impact.