Estimation of boundary conditions for patient-specific liver simulation during augmented surgery.

Purpose: Augmented reality can improve the outcome of hepatic surgeries, assuming an accurate liver model is available to estimate the position of internal structures. While researchers have proposed patient-specific liver simulations, very few have addressed the question of boundary conditions. Resulting mainly from ligaments attached to the liver, they are not visible in preoperative images, yet play a key role in the computation of the deformation.

Optical modeling in Testbed Environment for Space Situational Awareness (TESSA).

We describe optical systems modeling in the Testbed Environment for Space Situational Awareness (TESSA) simulator. We begin by presenting a brief outline of the overall TESSA architecture and focus on components for modeling optical sensors. Both image generation and image processing stages are described in detail, highlighting the differences in modeling ground- and space-based sensors.

Planomonadida ord. nov. (Apusozoa): ultrastructural affinity with Micronuclearia podoventralis and deep divergences within Planomonas gen. nov.

Gliding zooflagellates previously misidentified as Ancyromonas sigmoides, Metopion or Heteromita constitute a new genus Planomonas. Three new Planomonas species (marine P. micra and P.

Light echoes from ancient supernovae in the Large Magellanic Cloud.

The light from historical supernovae could in principle still be visible as scattered-light echoes centuries after the explosion. The detection of light echoes could allow us to pinpoint the supernova event both in position and age and, most importantly, permit the acquisition of spectra to determine the 'type' of the supernova centuries after the direct light from the explosion first reached Earth. Although echoes have been discovered around some nearby extragalactic supernovae, targeted searches have not found any echoes in the regions of historical Galactic supernovae.