W Thomas Thach8
Michael J Aziz3
Emily N Hathaway3
8W Thomas Thach
3Michael J Aziz
3Emily N Hathaway
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Energetic particle irradiation can cause surface ultra-smoothening, self-organized nanoscale pattern formation or degradation of the structural integrity of nuclear reactor components. A fundamental understanding of the mechanisms governing the selection among these outcomes has been elusive. Here we predict the mechanism governing the transition from(More)
We studied coordination across body parts in throwing during adaptation to prisms. Human subjects threw balls at a target before, during, and after wearing laterally shifting prism eyeglasses. Positions of head, shoulders, arm, and ball were video-recorded continuously. We computed body angles of eyes-in-head, head-on-trunk, trunk-on-arm, and arm-on-ball.(More)
Neuronal signals in the lateral aspect of the macaque cerebellar cortex were studied during a visually guided reaching task. During the performance of this task, the firing rate of most neurons was significantly modulated when reaching with either the ipsilateral or the contralateral arm. In some of these reach-modulated cells, we found that spike firing(More)
Complex (CS)- and simple-spike (SS) discharge from single Purkinje cells (Pc) in the posterolateral cerebellum of two monkeys was recorded during a visually guided reach-touch task. A visual target appeared (TA) off-gaze at a random location on a screen. On initiation of arm reach, the target disappeared, then reappeared (TR) after a fixed delay. TR was(More)
We develop a methodology for deriving continuum partial differential equations for the evolution of large-scale surface morphology directly from molecular dynamics simulations of the craters formed from individual ion impacts. Our formalism relies on the separation between the length scale of ion impact and the characteristic scale of pattern formation, and(More)
A number of studies have been interpreted to support the view that the inferior olive climbing fibers send periodic signals to the cerebellum to time and pace behavior. In a direct test of this hypothesis in macaques performing nonperiodic tasks, we analyzed continuous recordings of complex spikes from the lateral cerebellar hemisphere. We found no(More)
We consider the coarsening dynamics of multiscale solutions to a dissipative singularly perturbed partial differential equation which models the evolution of a thermodynamically unstable crystalline surface. The late-time leading-order behavior of solutions is identified, through the asymptotic expansion of a maximal-dissipation principle, with a completely(More)
  • Scott A Norris, Juha Samela, Matias Vestberg, Kai Nordlund, Michael J Aziz, S A Norris
  • 2013
During the ion bombardment of targets containing multiple component species, highly-ordered arrays of nanostructures are sometimes observed. Models incorporating coupled partial differential equations, describing both morphological and chemical evolution, seem to offer the most promise of explaining these observations. However, these models contain many(More)
In this grand rounds, we focus on development, validation, and application of neuroimaging biomarkers for Parkinson disease (PD). We cover whether such biomarkers can be used to identify presymptomatic individuals (probably yes), provide a measure of PD severity (in a limited fashion, but frequently done poorly), investigate pathophysiology of parkinsonian(More)
Three monkeys performed a visually guided reach-touch task with and without laterally displacing prisms. The prisms offset the normally aligned gaze/reach and subsequent touch. Naive monkeys showed adaptation, such that on repeated prism trials the gaze-reach angle widened and touches hit nearer the target. On the first subsequent no-prism trial the monkeys(More)