3D cryoimaging of cell-mediated cholesterol crystal clearance in human atherosclerotic lesions.

We applied micro-computed tomography, high-resolution cryo-scanning electron microscopy (SEM) combined with cathodoluminescence, and cryo-focused ion beam Milling-SEM to perform three-dimensional imaging of human atherosclerotic tissues with tens of nanometers resolution, under hydrated, near-native conditions with minimal sample processing. The same technology was applied to cultured macrophages exposed to cholesterol crystals, and the observations made on the macrophages were compared to those made on the pathological tissue. We observed that cholesterol crystal digestion and, eventually, cholesterol crystal clearance occurs in the advanced human plaques through cellular processing.

Perspectives on facilitating dynamic ecology courses online using active learning.

As education methodology has grown to incorporate online learning, disciplines with a field component, like ecology, may find themselves sidelined in this transition. In response to challenges posed by moving classes online, previous studies have assessed whether an online environment can be effective for student learning. This work has found that active learning structures, which maximize information processing and require critical thinking, best support student learning.