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In this study, passive acoustic monitoring was used to assess the impact of investigator disturbance on the acoustic behavior of a colony of common terns. A graded antipredator response in the colony was hypothesized, which would result in an increase in acoustic energy with increased proximity to investigator disturbance. Human disturbance was found to result in a significant increase in acoustic energy within 20 meters of recorders, though not from farther distances. Our findings provide a framework for assessing the behavioral impact of disturbance on colonies and support the existence of a graded alarm call system in common terns. 

We present the first 3D kinematic analysis of multiple stellar populations (MPs) in a representative sample of 16 Galactic globular clusters (GCs). For each GC in the sample, we studied the MP line-of-sight, plane-of-the-sky and 3D rotation, and velocity distribution anisotropy. The differences between first-population (FP) and second-population (SP) kinematic patterns were constrained by means of parameters specifically defined to provide a global measure of the relevant physical quantities and to enable a meaningful comparison among different clusters. Our analysis provides the first observational description of the MP kinematic properties and of the path they follow during their long-term dynamical evolution. In particular, we find evidence of differences between the rotation of MPs along all velocity components with the SP preferentially rotating faster than the FP. The difference between the rotation strength of MPs is anticorrelated with the cluster dynamical age. We also observe that FPs are characterized by isotropic velocity distributions at any dynamical age probed by our sample. On the contrary, the velocity distribution of SP stars is found to be radially anisotropic in dynamically young clusters and isotropic at later evolutionary stages. The comparison with a set of numerical simulations shows that these observational results are consistent with the long-term evolution of clusters forming with an initially more centrally concentrated and more rapidly rotating SP subsystem. We discuss the possible implications these findings have on our understanding of MP formation and early evolution. 

The current work studies the correlations between microstructure and retained austenite (RA) transformation, in a single-quenched and partitioned (Q&P) 1180 steel microstructure, through in situ tensile tests combined with electron backscatter diffraction (EBSD) analysis. This allows the study of RA stability across a limited range of morphological characteristics to be studied in the absence of confounding factors introduced by varying the entire steel microstructure. Among the microstructural attributes of interest, RA grain aspect ratio is found to have the largest influence on transformation rate, where globular-shaped grains transform more slowly than those with a more lenticular shape. Furthermore, by tracking individual grains during deformation, it is apparent that larger grains transformed more slowly than smaller grains; a purely statistical study of grain size vs strain might conclude that smaller grains are more stable, but in reality, the smaller grains transform faster and are simply statistically replaced by partially transformed larger grains. These conclusions are in contrast to relationships that might be inferred from previous studies where the entire steel microstructure was varied, along with the morphology of the RA. 

Experiential learning programs like internships and capstone projects are high-impact practices that allow engineering students to build a professional network, apply technical skills in a real-world context, and develop non-academic skills that employers need. In 2020 the COVID-19 pandemic and subsequent school closures impacted the entire engineering education ecosystem, particularly internships and other experiential learning opportunities. Virtual internship, an education intervention developed to broaden participation in experiential learning for non-traditional students, was rapidly deployed to address the disruption to internships caused by the COVID-19 pandemic. Key challenges that emerged during the implementation process include marketing the new program to existing partners, deciding on a remuneration structure, and navigating IP issues. The paper systematically steps through the implementation process and how the challenges mentioned above were addressed in practice. As life, school and internships return to normal in 2021 and beyond, the Virtual internship intervention can still play a valuable role in the experiential learning landscape. However, higher education institutions may need to intentionally de-couple the educational innovations rapidly developed during the COVID-19 pandemic from being ‘pandemic solutions’ to valuable alternatives that provide equitable and scalable access to educational opportunities and proactively invest in their continued sustainability and growth.