Rapid Step Test Based on Leg Length as a Novel Dynamic Standing Balance Test in the Geriatric Population: A Pilot Study

Each year, 1 out of 3 adults over age 65 experience a fall resulting in a traumatic injury or even mortality. Falls are the leading cause of death in the elderly population and cause the greatest number of hospital admissions from trauma. The Balance Evaluation Systems Test (BEST), Berg Balance Scale, and Tinetti are frequently used tests to determine fall risk. However, they can be complicated, time consuming, and exhibit a ceiling effect. This study employed the Rapid Step Test (RST) to examine the use and practicality of a new, portable and easy to administer test that may differentiate between fallers and non-fallers.https://ecommons.udayton.edu/dpt_symposium/1021/thumbnail.jp

Skunk River Review September 1990, vol 2

https://openspace.dmacc.edu/skunkriver/1005/thumbnail.jp

Predator-induced changes of female mating preferences: innate and experiential effects

Background: In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana). Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators. Results: In dichotomous choice tests predator-naïve (lab-reared) females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus). In contrast, predator experienced (wild-caught) females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey. Conclusions: Our study highlights that (a) predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection), and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b) Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c) Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators. Keywords: Sexual selection; female choice; non-independent mate choice; predator recognition; Poecilia mexican