Measurement procedures affect the interpretation of metatarsophalangeal joint function during accelerated sprinting

This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Sports Sciences on 7/8/2012, available online: http://wwww.tandfonline.com/10.1080/02640414.2012.713501The metatarsophalangeal joint (MPJ) is a significant absorber of energy in sprinting. This study examined the influence of MPJ axis choice and filter cut-off frequency on kinetic variables describing MPJ function during accelerated sprinting. Eight trained sprinters performed maximal sprints along a runway. Three dimensional high-speed (1000 Hz) kinematic and kinetic data were collected at the 20 m point. Three axis definitions for the five MPJs were compared. MPJ moments, powers and energies were calculated using different filter cut-off frequencies. The more anatomically appropriate dual axis resulted in less energy absorbed at the MPJ compared to the oblique axis which also absorbed less energy compared to the perpendicular axis. Furthermore, a low cut-off frequency (8 Hz) substantially underestimated MPJ kinematics, kinetics and the energy absorbed at the joint and lowered the estimate of energy production during push-off. It is concluded that a better understanding of MPJ function during sprinting would be obtained by using an oblique or anatomically appropriate representation of the joint together with appropriate kinematic data sampling and filtering so that high frequency movement characteristics are retained.This article was submitted to the RAE2014 for the University of Chester - Sport and Exercise Sciences, Leisure and Tourism

Photonic molecules and spectral engineering

This chapter reviews the fundamental optical properties and applications of pho-tonic molecules (PMs) - photonic structures formed by electromagnetic coupling of two or more optical microcavities (photonic atoms). Controllable interaction between light and matter in photonic atoms can be further modified and en-hanced by the manipulation of their mutual coupling. Mechanical and optical tunability of PMs not only adds new functionalities to microcavity-based optical components but also paves the way for their use as testbeds for the exploration of novel physical regimes in atomic physics and quantum optics. Theoretical studies carried on for over a decade yielded novel PM designs that make possible lowering thresholds of semiconductor microlasers, producing directional light emission, achieving optically-induced transparency, and enhancing sensitivity of microcavity-based bio-, stress- and rotation-sensors. Recent advances in material science and nano-fabrication techniques make possible the realization of optimally-tuned PMs for cavity quantum electrodynamic experiments, classical and quantum information processing, and sensing.Comment: A review book chapter: 29 pages, 19 figure

What the Brain Does before the Tongue Slips

Speech production is an extremely rapid and seemingly effortless process with speech errors in normal subjects being rare. Although psycholinguistic models incorporate elaborate monitoring mechanisms to prevent and correct errors, the brain regions involved in their commitment, detection, and correction have remained elusive. Using event-related brain potentials in a task known to elicit spoonerisms representing a special class of sound errors, we show specific brain activity prior to the vocalization of such spoonerisms. Source modeling localized this activity to the supplementary motor area in medial frontal cortex. We propose that this activity reflects the simultaneous activation of 2 competing speech plans on processing levels related to the construction of a rather "phonetic" speech plan contrasting with the traditional view, assuming the substitution of abstract phonological representations as the main source for sound errors