Adaptive Frequency Neural Networks for Dynamic Pulse and Metre Perception.

Beat induction, the means by which humans listen to music and perceive a steady pulse, is achieved via a perceptualand cognitive process. Computationally modelling this phenomenon is an open problem, especially when processing expressive shaping of the music such as tempo change.To meet this challenge we propose Adaptive Frequency Neural Networks (AFNNs), an extension of Gradient Frequency Neural Networks (GFNNs).GFNNs are based on neurodynamic models and have been applied successfully to a range of difficult music perception problems including those with syncopated and polyrhythmic stimuli. AFNNs extend GFNNs by applying a Hebbian learning rule to the oscillator frequencies. Thus the frequencies in an AFNN adapt to the stimulus through an attraction to local areas of resonance, and allow for a great dimensionality reduction in the network.Where previous work with GFNNs has focused on frequency and amplitude responses, we also consider phase information as critical for pulse perception. Evaluating the time-based output, we find significantly improved re-sponses of AFNNs compared to GFNNs to stimuli with both steady and varying pulse frequencies. This leads us to believe that AFNNs could replace the linear filtering methods commonly used in beat tracking and tempo estimationsystems, and lead to more accurate methods

Bayesian inference of nanoparticle-broadened x-ray line profiles

A single and self-contained method for determining the crystallite-size distribution and shape from experimental x-ray line profile data is presented. We have shown that the crystallite-size distribution can be determined without assuming a functional form for the size distribution, determining instead the size distribution with the least assumptions by applying the Bayesian/MaxEnt method. The Bayesian/MaxEnt method is tested using both simulated and experimental CeO$_{2}$ data. The results demonstrate that the proposed method can determine size distributions, while making the least number of assumptions. The comparison of the Bayesian/MaxEnt results from experimental CeO$_2$ with TEM results is favorableComment: 43 pages, 13 Figures, 5 Table

Copy of letter and paper J. N. Armstrong sent to the War Department

Copy of letter and paper from J. N. Armstrong to the War Department that was presumably sent to B. R. Colson. The one-page typewritten letter is on Harding College letterhead and dated 13 October 1935. The copy of the paper sent to the War Department, Prepared for War, is one-page long

Sex-Specific Longitudinal Modeling of Youth Peak Oxygen Uptake.

This is the publisher formatted version. The final version is available from Human Kinetics via the DOI in this record.PURPOSE: To investigate peak oxygen uptake ([Formula: see text]) in relation to sex, age, body mass, fat-free mass (FFM), maturity, and overweight status. METHODS: Multiplicative, allometric models of 10- to 18-year-olds were founded on 1057 determinations of peak [Formula: see text] supported by anthropometry and estimates of maturity status. RESULTS: Baseline models with body mass controlled for showed age to exert a positive effect on peak [Formula: see text], with negative estimates for age2, sex, and a sex-by-age interaction. Sex-specific models showed maturity status to have a positive effect on peak [Formula: see text] in addition to the effects of age and body mass. Introducing skinfold thicknesses to provide, with body mass, a surrogate for FFM explained maturity effects and yielded a significantly (P < .05) better statistical fit in all models compared with those based on FFM estimated from youth-specific skinfold equations. With girls only, the introduction of overweight, defined by body mass index, resulted in a small but significant (P < .05) negative effect, with an age-by-overweight status interaction. CONCLUSIONS: FFM has a powerful influence on peak [Formula: see text] in both sexes. Interpretation of the development of youth aerobic fitness and its application to health should reflect the sex- and maturity-associated variation in FFM.British Heart FoundationCommunity FundDarlington Trus

Interpreting Aerobic Fitness in Youth: The Fallacy of Ratio Scaling.

This is the final version. Available on open access from Human Kinetics via the DOI in this recordIn this paper, we draw on cross-sectional, treadmill-determined, peak oxygen uptake data, collected in our laboratory over a 20-year period, to examine whether traditional per body mass (ratio) scaling appropriately controls for body size differences in youth. From an examination of the work of pioneering scientists and the earliest studies of peak oxygen uptake, we show how ratio scaling appears to have no sound scientific or statistical rationale. Using simple methods based on correlation and regression, we demonstrate that the statistical relationships, which are assumed in ratio scaling, are not met in groups of similar aged young people. We also demonstrate how sample size and composition can influence relationships between body mass and peak oxygen uptake and show that mass exponents derived from log-linear regression effectively remove the effect of body mass. Indiscriminate use of ratio scaling to interpret young people's fitness, to raise "Clinical Red Flags", and to assess clinical populations concerns us greatly, as recommendations and conclusions based upon this method are likely to be spurious. We urge those involved with investigating youth fitness to reconsider how data are routinely scaled for body size.Darlington Trus

Sex-Specific Longitudinal Modeling of Short-Term Power in 11-18 Year-Olds

This is the author accepted manuscript. Available from Lippincott, Williams & Wilkins via the DOI in this record.PURPOSE: To investigate, longitudinally, short-term power output in relation to sex and concurrent changes in age, body mass, fat free mass (FFM), and maturity status. METHODS: Multiplicative multilevel modeling which enables the effects of variables to be partitioned concurrently within an allometric framework was used to analyze the peak power (PP) and mean power (MP) of 388 11-18 year-olds. Multilevel models were founded on 763 (405 from boys; 358 from girls) determinations of PP and MP from Wingate anaerobic tests, supported by anthropometric measures and maturity status. RESULTS: In both sexes, PP and MP were significantly (p<0.001) correlated with age, body mass, and FFM. After controlling for body mass, initial models showed positive effects for age on PP and MP, with negative effects for sex and a sex by age interaction. Sex-specific models showed maturity status to have no additional effect on either PP or MP once age and body mass had been controlled for. Skinfold thicknesses in addition to body mass to provide a surrogate for FFM, yielded a significantly (p<0.05) better statistical fit in all models compared to those based on either body mass or FFM estimated from youth-specific skinfold equations. Models founded on estimated FFM provided a significantly (p<0.05) better fit than those based on body mass. ConclusionsWith body mass controlled for boys' PP and MP are higher than those of girls and sex differences increase with age from 11-18 years. A multilevel modeling approach has showed that in both sexes the most powerful influences on short-term power output are concurrent changes in age and FFM as reflected by the combination of body mass and skinfold thicknesses.Community FundDarlington TrustBritish Heart Foundatio