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Abstract Stingless bees (Hymenoptera: Apidae: Meliponini) are key pollinators of both cultivated and wild plants in tropical and subtropical areas of the world. While most species are found in lowland to mid-elevations, a few have adapted to high elevations, and their biology remains poorly understood. We assess the foraging pattern ofParapartamona zonata(Smith) in the central Andes of Colombia (2583 m.a.s.l.) and apply computer tomography to visualize and characterize its internal nest architecture. Bees foraged for pollen and nesting materials (resin and/or mud) from sunrise (5:40 h) to sunset (17:45), even at ambient temperatures as low as 11 °C. Foraging varied significantly throughout the day and temperature and sky condition explained 47% of its variance. Differences in the nest architecture, when compared with previous records, suggest that nesting behavior might be variable. These results are discussed in the context of behavioral adaptations in this unique environmental niche. 

Abstract Due to the Covid‐19 pandemic, the education system worldwide faced sudden and unforeseen challenges. Many academic institutions closed their doors, forcing both educators and students to transition to Emergency Remote Teaching (ERT) for the remainder of the semester. This transition eliminated hands‐on experiences, increased workload, and altered curricula. However, these aspects, as well as students' perceptions, study habits, and performance in response to ERT remain poorly documented. This contribution describes changes in the curriculum of an undergraduate cadaver‐based laboratory, and explores students' performance, self‐perceived learning, and overall satisfaction during this educational crisis. Online content delivery for this course included both asynchronous instruction and synchronous discussion sessions. While formative assessments remained the same, online spotter examinations included short answer, multiple choice, multiple answer, ordering, and true and false questions. Despite examination grades improving 20% during ERT, students reported lower levels of learning, confidence, and engagement with the course materials when compared to the face‐to‐face portion of the class. The most prevalent challenges identified by students were those related to the loss of access to cadaver‐based learning, including difficulty identifying and visualizing structures in three dimensions, and the loss of context and sensorial cues. Flexibility in taking examinations and learning the material at their own pace were recognized as positive outcomes of the ERT transition. While the resulting student perceptions and performances are unsurprising, they offer insight into the challenges of fostering a productive learning environment in a future threatened by epidemic outbreak and economic uncertainty. 

Abstract Insulator‐based dielectrophoresis (iDEP) is the electrokinetic migration of polarized particles when subjected to a non‐uniform electric field generated by the inclusion of insulating structures between two remote electrodes. Electrode spacing is considerable in iDEP systems when compared to electrode‐based DEP systems, therefore, iDEP systems require high voltages to achieve efficient particle manipulation. A consequence of this is the temperature increase within the channel due to Joule heating effects, which, in some cases, can be detrimental when manipulating biological samples. This work presents an experimental and modeling study on the increase in temperature inside iDEP devices. For this, we studied seven distinct channel designs that mainly differ from each other in their post array characteristics: post shape, post size and spacing between posts. Experimental results obtained using a custom‐built copper Resistance Temperature Detector, based on resistance changes, show that the influence of the insulators produces a difference in temperature rise of approximately 4°C between the designs studied. Furthermore, a 3D COMSOL model is also introduced to evaluate heat generation and dissipation, which is in good agreement with the experiments. The model allowed relating the difference in average temperature for the geometries under study to the electric resistance posed by the post array in each design.