A dynamic model of the breast during exercise

The aim of this paper is to develop a method to determine the material characteristics of bras that could limit breast motion during exercise. A single participant ran on a treadmill at 10 km h−1 wearing either a sports bra, an everyday bra or no bra. The relative motion between the suprasternal notch and the breast was recorded using a passive marker system at 200 Hz and was modelled as forced damped-harmonic motion with a linear spring and damper, with the driving force provided by the suprasternal notch. The spring and damper values were found by matching the model to the experimental data. It was found that both the damping and stiffness values increased with the use of an everyday bra, and increased further still with the use of a sports bra. The stiffness parameter, however, was shown to be the most important criterion for minimisation of the breast motion. The model predicted that an increase in breast mass from 100 to 700 g (a 32A-cup to a 32F-cup) increased the vertical motion of the unsupported breast by around 70% when running and 30% when walking. This was reduced with an everyday bra and further reduced with the high stiffness sports bra. Although predictions were sensible, the model requires further verification with a cohort of participants

Gait stability during shod and barefoot walking and running on a treadmill assessed by correlation entropy

This study tests correlation entropy, 2, as a measure of stability for gait analysis. An average of 13 strides from 10 participants in each combination of one footwear (barefoot vs shod) condition and one gait mode (walking vs running) were collected during treadmill walking and running. Sagittal plane ankle, knee and hip angular displacement and velocity data were used for analysis. Two-way repeated measures ANOVA showed a main effect for gait mode ( =.03 ) – running had lower 2 than walking, indicating higher stability. Although the sample of strides and participants was small, we speculate that the greater inertia for running helped stabilize movement control, making the running coordination pattern more resilient against small stride-to-stride perturbations.Peer Reviewe

Bone Accumulation by Leopards in the Late Pleistocene in the Moncayo Massif (Zaragoza, NE Spain)

Eating habits of Panthera pardus are well known. When there are caves in its territory, prey accumulates inside them. This helps to prevent its kill from being stolen by other predators like hyenas. Although the leopard is an accumulator of bones in caves, few studies have been conducted on existing lairs. There are, however, examples of fossil vertebrate sites whose main collecting agent is the leopard. During the Late Pleistocene, the leopard was a common carnivore in European faunal associations. Here we present a new locality of Quaternary mammals with a scarce human presence, the cave of Los Rincones (province of Zaragoza, Spain); we show the leopard to be the main accumulator of the bones in the cave, while there are no interactions between humans and leopards. For this purpose, a taphonomic analysis is performed on different bone-layers of the cave