Human pluripotent stem cell (hPSC)-derived neural organoids display unprecedented emergent properties. Yet in contrast to the singular neuroepithelial tube from which the entire central nervous system (CNS) develops in vivo, current organoid protocols yield tissues with multiple neuroepithelial units, a.k.a. neural rosettes, each acting as independent morphogenesis centers and thereby confounding coordinated, reproducible tissue development. Here, we discover that controlling initial tissue morphology can effectively (>80%) induce single neural rosette emergence within hPSC-derived forebrain and spinal tissues. Notably, the optimal tissue morphology for observing singular rosette emergence was distinct for forebrain versus spinal tissues due to previously unknown differences in ROCK-mediated cell contractility. Following release of geometric confinement, the tissues displayed radial outgrowth with maintenance of a singular neuroepithelium and peripheral neuronal differentiation. Thus, we have identified neural tissue morphology as a critical biophysical parameter for controlling in vitro neural tissue morphogenesis furthering advancement towards biomanufacture of CNS tissues with biomimetic anatomy and physiology.

Foodborne illness ranks seventh globally among major health hazards, falling between air pollution and tuberculosis. Yet food safety is relatively understudied by economists. This paper provides an introduction to food safety for economists new to the subject. It presents an overview of the problem, the history of major policy reforms, and the structure of food safety governance in the United States and internationally. It identifies potential opportunities for economists in interdisciplinary food safety research and presents one example of this kind of collaboration, namely research focused on identifying the food sources of US Campylobacter infections.

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