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In this paper we consider the problem of segmenting n aligned random sequences of equal length m into a finite number of independent blocks. We propose a penalized maximum likelihood criterion to infer simultaneously the number of points of independence as well as the position of each point. We show how to compute exactly the estimator by means of a dynamic programming algorithm with time complexity O ( m 2 n ) . We also propose another method, called hierarchical algorithm, that provides an approximation to the estimator when the sample size increases and runs in time O { m ln ( m ) n } . Our main theoretical results are the strong consistency of both estimators when the sample size n grows to infinity. We illustrate the convergence of these algorithms through some simulation examples and we apply the method to identify recombination hotspots in real SNPs data. [ABSTRACT FROM AUTHOR]

Supplemental digital content is available in the text. Purpose: This study aimed to describe the kinetics of carnosine washout in human skeletal muscle over 16 wk. Methods: Carnosine washout kinetics were studied in 15 young, physically active omnivorous men randomly assigned to take 6.4 g·d−1 of β-alanine (n = 11) or placebo (n = 4) for 8 wk. Muscle carnosine content (M-Carn) was determined before (PRE), immediately after (POST), and 4, 8, 12, and 16 wk after supplementation. High-intensity exercise tests were performed at these same time points. Linear and exponential models were fitted to the washout data, and the leave-one-out method was used to select the model with the best fit for M-Carn decay data. Repeated-measures correlation analysis was used to assess the association between changes in M-Carn and changes in performance. Results: M-Carn increased from PRE to POST in the β-alanine group only (+91.1% ± 29.1%; placebo, +0.04% ± 10.1%; P < 0.0001). M-Carn started to decrease after cessation of β-alanine supplementation and continued to decrease until week 16 (POST4, +59% ± 40%; POST8, +35% ± 39%; POST12, +18% ± 32%; POST16, −3% ± 24% of PRE M-Carn). From week 12 onward, M-Carn was no longer statistically different from PRE. Both linear and exponential models displayed very similar fit and could be used to describe carnosine washout, although the linear model presented a slightly better fit. The decay in M-Carn was mirrored by a similar decay in high-intensity exercise tolerance; M-Carn was moderately and significantly correlated with total mechanical work done (r = 0.505; P = 0.032) and time to exhaustion (r = 0.72; P < 0.001). Conclusions: Carnosine washout takes 12–16 wk to complete, and it can be described either by linear or exponential curves. Changes in M-Carn seem to be mirrored by changes in high-intensity exercise tolerance. This information can be used to optimize β-alanine supplementation strategies. [ABSTRACT FROM AUTHOR]