Stumping and Stunts: Walking in Circles in the “Go-As-You-Please” Race

New York City, 1884: 14 contestants set out to walk round and round a track for six days in the “go-as-you-please” race, taking as little rest as possible. What does this durational act tell us about a type of performance just beginning to be named in New York slang as a “stunt”? Anticipating early-20th-century dance marathons and later durational performance art, the race enacted and troubled circulation, revealing fault lines of valorization: between work and leisure, work and life, and sporting and theatrical performance

Evidence for a relationship between bilateral coordination during complex gait tasks and freezing of gait in Parkinson\u27s disease

BACKGROUND: Freezing of gait is a debilitating and common gait disturbance observed in individuals with Parkinson’s disease (PD). Although the underlying mechanisms of freezing remain unclear, bilateral coordination of steps, measured as a phase coordination index, has been suggested to be related to freezing. Phase coordination index has not, however, been measured during tasks associated with freezing such as turning and backward walking. Understanding how bilateral coordination changes during tasks associated with freezing may improve our understanding of the causes of freezing. METHODS: Twelve individuals with PD who freeze (freezers), 19 individuals with PD who do not freeze (non-freezers), and 10 healthy, age-matched older adults participated. General motor disease severity and freezing severity were assessed. Phase coordination index was calculated for all subjects during forward walking, backward walking, continuous turning in small radius circles, and turning in large radius circles. RESULTS: Freezers and non-freezers had similar disease duration and general motor severity. Stepping coordination (measured as phase coordination index) was significantly worse in freezers compared to non-freezers and controls. Turning and backward walking, tasks related to freezing, resulted in worse coordination with respect to forward walking. Coordination was associated with severity of freezing scores such that worse coordination was correlated with more severe freezing. CONCLUSIONS: These results provide evidence that stepping coordination is related to freezing in people with PD. Identifying variables associated with freezing may provide insights into factors underlying this symptom, and may inform rehabilitative interventions to reduce its occurrence in PD

Walkable Gettysburg— How Pedestrian Friendly is the Borough of Gettysburg, Pennsylvania?

Walkability is a measure of how easily pedestrians can reach a variety of destinations via walking. Greater walkability has been linked to several benefits, including improvements in human health, economic stimulus, and improved air quality. We surveyed 37 blocks in Gettysburg, Pennsylvania to record the presence of 13 design factors such as street trees and pedestrian oriented amenities that have been shown to encourage walking. These results were then compared with the Walk Score from walkscore.com, a common measurement tool of walkability. Based on the surveys, we calculated a design quality score (DQI) for each block. There was no correlation between DQI and Walk Score. The highest scores for aesthetics were recorded near Gettysburg College, the highest scores for ease of use were recorded around the traffic circle at the center of town, and the highest scores for safety were recorded near the traffic circle and the College. We believe that this discrepancy can be attributed to the focus of walkscore.com on the proximity of a location to various destination while our DQI score considered aesthetics, ease of use, and safety. Based on the results of this study, we recommend that the borough of Gettysburg invest in alternatives to automobile transport such as bicycle oriented amenities in order to increase walkability

Dynamics of Human Walking

The problem of biped locomotion at steady speeds is discussed through a Lagrangian formulation developed for velocity-dependent, body driving forces. Human walking on a level surface is analyzed in terms of the data on the resultant ground-reaction force and the external work. It is shown that the trajectory of the center of mass is due to a superposition of its rectilinear motion with a given speed and a backward rotation along a shortened hypocycloid. A stiff-to-compliant crossover between walking gaits is described and the maximum speed for human walking, given by an instability of the trajectory, is predicted. Key words: locomotion, integrative biology, muscles, bipedalism, human walking, biomechanics.Comment: 9 pages, 4 figure

A Computational Study of Thirteen-atom Ar-Kr Cluster Heat Capacities

Heat capacity curves as functions of temperature were calculated using Monte Carlo methods for the series of Ar_{13-n}Kr_n clusters (0 <= n <= 13). The clusters were modeled classically using pairwise additive Lennard-Jones potentials. J-walking (or jump-walking) was used to overcome convergence difficulties due to quasiergodicity present in the solid-liquid transition regions, as well as in the very low temperature regions where heat capacity anomalies arising from permutational isomers were observed. Substantial discrepancies between the J-walking results and the results obtained using standard Metropolis Monte Carlo methods were found. Results obtained using the atom-exchange method, another Monte Carlo variant designed for multi-component systems, were mostly similar to the J-walker results. Quench studies were also done to investigate the clusters' potential energy surfaces; in each case, the lowest energy isomer had an icosahedral-like symmetry typical of homogeneous thirteen-atom rare gas clusters, with an Ar atom being the central atom.Comment: 46 pages, 13 Figures combined in 2 .gif files, Journal of Chemical Physics, AIP ID number 508646JC