Publications by authors named "Nicolas Gac"

Model-Based Iterative Reconstruction (MBIR) algorithms iteratively use expensive computational operators of forward and backward projections. The irregular memory access pattern of these operators makes them a memory-bound application. Their computation time must be reduced to meet clinical routine constraints.

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In this paper, a hierarchical prior model based on the Haar transformation and an appropriate Bayesian computational method for X-ray CT reconstruction are presented. Given the piece-wise continuous property of the object, a multilevel Haar transformation is used to associate a sparse representation for the object. The sparse structure is enforced via a generalized Student- distribution ( S t g ), expressed as the marginal of a normal-inverse Gamma distribution.

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DNA polymerase ε (pol ε) is believed to be the leading strand replicase in eukaryotes whereas pols λ and β are thought to be mainly involved in re-synthesis steps of DNA repair. DNA elongation by the human pol ε is halted by an abasic site (apurinic/apyrimidinic (AP) site). We have previously reported that human pols λ, β and η can perform translesion synthesis (TLS) of an AP site in the presence of pol ε.

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