We consider an elastic model for a circular arch that incorporates membrane, transverse shear, and bending effects. The central line of the arch is partitioned into elements, and an ultra-weak variational formulation is developed alongside a discontinuous Petrov–Galerkin (DPG) approximation procedure based on so-called optimal test functions. The formulation uses discontinuous stress and displacement interpolations on the element mesh, with corresponding interface variables defined at the nodes. Theoretical analysis establishes well-posedness and quasi-optimal convergence properties of the DPG approximation, while also revealing potential error amplification influenced by the curvature of the arch and the imposed boundary conditions. The method is tested on examples with different support configurations. The numerical experiments confirm the theoretical predictions and further demonstrate that the accuracy of the DPG method can be improved by employing a suitably scaled test space norm.
How can recovery trajectories after critical illness in very old ICU survivors be better understood and potentially modified across the continuum of care? Recovery trajectories in very old ICU survivors are highly heterogeneous and result from the interaction between baseline vulnerability (frailty, multimorbidity, social factors), the acute stress of critical illness, and individual resilience. Opportunities to influence these trajectories exist at multiple stages, including prehabilitation before ICU admission,brain- and neuromuscular-protective strategies during ICU stay, and structured, transdisciplinary post-ICU follow-up. A shift from survival-focused metrics to a trajectory-based, transdisciplinary approach is essential to improve functional recovery and quality of life in very old ICU survivors.
The use of mobile dataloggers to gather proximity data has generated novel insights into the social network structure of animals. The performance of mobile dataloggers may be impacted by different environmental and social conditions. Thus, validation studies that account for species-specific habitat use and behavior are essential. We conducted a series of validation studies of two brands of mobile dataloggers (Gipsy6, Technosmart, Italy; ProxLog, IoSA, Belgium) on the semi-fossorial rodent, Octodon degus. First, we determined the sensitivity of both types of dataloggers to track position and closeness in different habitats (Experiments 1 and 2). To determine if the structure of the network is influenced by the kind of data collected, we compared social networks generated by the two datalogger types and a passive monitoring RFID (radio frequency identification) system previously used in our study system (Experiment 3). The Gipsy6 units were more sensitive in open areas, within shrubs, and when into a burrow opening than ProxLog units. Mantel tests revealed that networks based on Gipsy6 and ProxLog units were weakly correlated with those from the RFID system. Both the group-level (weight, density, and eigenvector) and node-level (eigenvector) network metrics generated by the Gipsy6 and ProxLog dataloggers were not correlated with RFID. Degus carrying both types of dataloggers lost 7
This study addresses two challenges in fire-induced spalling of high-strength concrete (HSC): the limited reproducibility of small-scale fire testing methods and the need for sustainable alternatives to polypropylene fibers (PPFs). An Improved Torch Method (ITM) was developed as a low-cost comparative assessment method by introducing a temperature-stabilization stage prior to specimen exposure, and validated against the Traditional Torch Method (TTM) using control and PPF-reinforced concrete mixtures. The validated ITM was then applied to evaluate keratin-based dog hair fibers (DHFs) as a sustainable alternative to PPFs. The ITM reduced the coefficient of variation (COV) of residual strength results from 19.5
This study examined how attentional traits (mind wandering and mindfulness) and metacognitive knowledge relate to creative thinking across educational levels in Chile. Two studies were conducted. Study 1 included 130 university students from a highly selective private university and a nonselective private university. Study 2 included 170 high school students from a public, a state-subsidized, and a private school. Participants completed self-report measures of mind wandering, mindfulness, and metacognitive knowledge, along with assessments of verbal divergent thinking, verbal convergent thinking, and figural creative thinking. Structural equation models revealed distinct patterns across educational levels. In university students, institutional selectivity was positively associated with verbal convergent thinking. Verbal convergent thinking was positively associated with the Describing facet of mindfulness and negatively associated with Independent Thinking and Nonjudging. Verbal divergent thinking was positively associated with Daydreaming, whereas figural creative thinking was positively associated with Study Strategies. In high school students, school type was strongly associated with verbal convergent and figural creative thinking, with students from the state-subsidized school performing worse than those from the public school and the private school. Also, students from the private school performed better than those from the public school in verbal convergent thinking. Verbal convergent and figural creative thinking were not significantly associated with self-report measures. Verbal divergent thinking, however, was positively related to Study Strategies and Observing and negatively related to Independent Thinking. Unclustered structural equation models were also tested in both studies. Differences between clustered and unclustered models suggest that institutional context accounted for substantial variance and overshadowed several associations observed in unclustered models. These findings highlight the central role of educational context in shaping creative thinking and its metacognitive and attentional correlates, underscoring the need for research that explicitly models how learning environments moderate or constrain relationships between metacognition, attentional traits, and creativity.
