Abstract: Bio-loggers are miniaturized autonomous devices that record quantitative data on the state of free-ranging animals (e.g. behavior, position and physiology) and their natural environment. This is especially relevant for species where direct visual observation is difficult or impossible. Today, ongoing technical development allows the monitoring of numerous parameters in an increasing range of species over extended periods. However, the external attachment of devices might affect various aspects of animal performance (energetics, thermoregulation, foraging as well as social and reproductive behavior), which ultimately affect fitness. External attachment might also increase entanglement risk and the conspicuousness of animals, leaving them more vulnerable to predation. By contrast, implantation of devices can mitigate many of these undesirable effects and might be preferable, especially for long-term studies, provided that the many challenges associated with surgical procedures can be mastered. Implantation may then allow us to gather data that would be impossible to obtain otherwise and thereby may provide new and ecologically relevant insights into the life of wild animals. Here, we: (i) discuss the pros and cons of attachment methods; (ii) highlight recent field studies that used implanted bio-loggers to address eco-physiological questions in a wide range of species; and (iii) discuss logger implantation in light of ethical considerations.

Abstract: In this paper the impact of the muon radial ionization profile on Single-Event Upset (SEU) sensitivity for nanoscale technologies is investigated with simulations and experimental measurements. The physical model used in the simulation framework is compared with experimental measurements of the charge deposit induced by atmospheric particles on a CCD pixel array. This scientific instrument is used to monitor the atmospheric muons, and allows to investigate the charge deposition induced by muon of micrometric sensitive volumes (i.e. the CCD pixel). Atmospheric and underground sites are considered for monitoring pixel-charge events and the combined analysis of the data is used to discriminate muons from other particles. 3D descriptions of muon tracks were simulated with radiation transport code Geant4, and coupled with Single Event Effect (SEE) simulation based on multi-physics approaches (MUSCA SEP3) to investigate the SEU cross-section and Soft Error Rate (SER) trends as function of technological downscaling. SER trends are analyzed for bulk technologies, from 65 to 14 nm integration nodes, in both ground and avionic environments. Results show that for technologies whose characteristic lengths are greater than 50 nm, it is not necessary to consider radial energy deposit structure of muon in SEE assessment. At ground, downscaling of the technological node induces an increase in the SEU susceptibility to cosmic ray showers, mainly because of muons. For nanoscale devices operating at avionic altitude, the muon contribution to the SER is very weak in comparison of the proton and neutron contributions.