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Biology subjects

Campana, C.

Publications and source records attributed to Campana, C..

2 recordsLinked to original sources

Green turtle satellite telemetry: identifying spatial movements, residency patterns, and habitat associations in Aotearoa New Zealand

Sea turtle conservation relies largely on the identification of ecologically significant marine areas. Green sea turtles (Chelonia mydas) are resident in Aotearoa New Zealand waters, yet much of their spatial ecology remains undefined. To address this, satellite telemetry was used to map juvenile and sub-adult green sea turtle spatial movements, residency patterns, and habitat associations. Our findings provide the first evidence of individual fine-scale habitat use and long-term residency in New Zealand waters. Data will contribute to regional and global efforts to identify ecologically significant sea turtle habitat, including Important Marine Turtle Areas (IMTAs) and Blue Corridors for Turtles (BC4T), and help advance conservation efforts.

zoology↗

Coupling and Heterogeneity Modulate Pacemaking Capability in Healthy and Diseased Two-Dimensional Sinoatrial Node Tissue Models

Both experimental and modeling studies have attempted to determine mechanisms by which a small anatomical region, such as the sinoatrial node (SAN), can robustly drive electrical conduction in the human heart. However, despite important advances from prior research, important questions remain unanswered. This study aimed to investigate, through mathematical modeling, the role of intercellular coupling and cellular heterogeneity in synchronization and pacemaking within the healthy and diseased SAN. In a multicellular computational model of a monolayer of either human or rabbit SAN cells, simulations revealed that heterogenous cells synchronize their discharge frequency into a unique beating rhythm across a wide range of cellular heterogeneity and intercellular coupling. However, an insightful and unanticipated behavior appears in pathological conditions precipitated by perturbations of certain ionic currents (gCaL = 0.5): an intermediate range of intercellular coupling (900-4000 M{Omega}) is beneficial to the human SAN automaticity, enabling a very small portion of tissue (3.4%) to drive propagation, which fails with both lower and higher resistances. This protective effect of intercellular coupling and heterogeneity, seen in both human and rabbit tissues, highlights the remarkable resilience of the SAN. Overall, the model here developed allowed insight into the mechanisms of automaticity of the human sinoatrial node. The simulations suggest that certain degrees of gap junctional expressions protect the SAN from ionic perturbations that might be caused by drugs or mutations.

physiology↗