Using Environmental Physiology to Teach Physiological Regulation

Environmental Physiology at Boise State University, Idaho, is a multidisciplinary course that expands students’ understanding of human regulatory physiology through acute and chronic responses to environmental extremes. Students explore the physics (pressure, fluid dynamics, gas laws, sound, and light) of the underwater environment, marine flora and fauna adaptations to this environment, and the human experience within this environment. Included is completion of the Professional Association of Dive Instructors (PADI) Open Water Scuba Certification. The course culminates in an international dive trip where course concepts are further demonstrated and explored, and conservation activities are undertaken.

Keeping environmental physiology education up and running during the COVID-19 pandemic

The COVID-19 pandemic provoked a need for rapid adaptation of teaching strategies and learning environments. Thus novel approaches, predominantly based on online/virtual platforms are needed to minimize the negative effects of the pandemic on teaching (and learning). Herein we describe our recent web-based symposium series on environmental physiology and ergonomics initiative as an example of such a strategy. We outline the ideas behind this series and its implementation, which could serve as an example of a useful joint interactive virtual educational environment that could be applied to any physiology subspecialty. Based on the feedback received from all stakeholders involved in the process, we strongly believe that such an approach can provide an excellent platform for all educational levels from undergraduate students up to seasoned academics. Importantly, the unrestricted availability (free registration and publication of recordings and student handouts) is an important consideration for the democratization of science and the inclusion of financially less well-supported students and academics.

Extreme fluid dynamic simulations reveal environmentally-driven morphological features of Euplectella aspergillum

Due to its remarkable structural properties as well as its tantalising beauty, silica depth sponge Euplectella aspergillum has attracted the interest of scientists all over the world since its discovery [1, 2]. Its skeletal system, in fact, is composed of amorphous hydrated silica and it is arranged in a highly regular and hierarchical cylindrical lattice, endowing the whole structure with an amazing flexibility and resilience to damage, [3-7]. In contrast with the major interest in the mechanical properties of the skeletal structure of these hexatinellida, the study of the hydrodynamic fields which surround and penetrate the glassy sponge has remained largely unexplored to date, leaving an open question as to the impact of fluid dynamic patterns on Euplectella's environmental physiology. A particularly outstanding question in this respect is whether, besides boosting its tribological characteristics, the structural motifs of Euplectella may also respond to an optimisation design in terms of minimising the hydrodynamic stress experienced by the structure. This is precisely the question addressed in the present work. To this purpose, we resort to extreme fluid dynamic simulations based on the Lattice Boltzmann Method [8], featuring of the order of one hundred billion grid points and spanning four spatial decades, from the micro-scale details of the skeleton, all the way up to the full structure of Euplectella. Such in-silico experiments reproduce the actual living conditions of Euplectella [9-11], and prove that the sponge structural elements, not only reduce the overall hydrodynamic stress experienced by the skeletal structure, but also support coherent internal recirculation patterns, arguably feeding the sponge and its host organisms. The present results open the path towards a new class of numerical investigations at the intersection between fluid mechanics, computational biology and environmental physiology.