Simulated annealing in ocular adaptive optics.

We present what is to our knowledge a first hardware realization of a simulated annealing algorithm in an adaptive optics system designed to image the retina of the human eye. The algorithm is applied to the retinal image itself without the need for wavefront sensors in the system. We find that this optimization algorithm can be an alternative to the traditional Hartmann-Shack sensing. We also compare the simulated annealing algorithm to the stochastic parallel gradient descent algorithm.

Anti-oxidant treatment for shock: vitamin E but not vitamin C improves survival.

Anti-oxidant therapy has been effective for treatment of experimental shock. In this study, the efficacy of Trolox (Aldrich Chemical Co., Milwaukee, WI), a water-soluble vitamin E analogue, and ascorbic acid (vitamin C) was evaluated in a rat model of hemorrhagic shock and resuscitation. In two prospective trials, rats were phlebotomized (27 mL/kg) and left in shock for 45 minutes. Resuscitation was then instituted by continuous IV infusion with lactated Ringer's (LR) (54 mL/kg) over 60 min. In Trial 1, rats were randomized to receive either placebo (LR) or Trolox (50 mg/kg) in LR. In Trial 2, rats were randomized to LR alone or ascorbic acid (50 mg/kg) in LR. Survival for ascorbic acid-treated rats (35 per cent) was not different than for control rats (35 per cent). However, the addition of Trolox to infusion significantly improved 72 hour survival, 75 per cent versus 40 per cent respectively, for Trolox-treated and control animals. These data demonstrate that Trolox is of survival benefit when added to resuscitation in this model. This benefit does not appear to be related to blood pressure or white cell adhesion. Trolox is more effective than ascorbic acid in this model.