Dancers across all styles use their spine as a main form of design in their posture and movements. The shape of the lumbar spine of the lower back is of particular interest, because it defines the line of the body. We hypothesize, therefore, that dancers, who have danced for longer than ten years, are able to change the shape of their lower spine. Through this study we examine the variations in curvature of the lumbar spine between different dancers walking in multiple common dance forms. Nine females aged 18-30 years walked at a normal pace in four different forms: regular walking, toe-ball-heel and neutral pelvis, toe-ball-heel and posterior pelvic tilt, and posterior pelvic tilt with regular foot form. An 8-camera Qualisys system was used to measure 3D trajectories of markers placed on fixed anatomical landmarks. We determined the curvature of lumbar spine in the participants by fitting a circle through the position of the lumbar spine markers in each frame. We found that six of nine participants were able to change significantly the curvature of their spines (p < 0.05).

Sexual dimorphism in biacetabular breadth in modern humans is believed to have developed in response to selective pressures for both a short lever arm from the body center of gravity to the acetabulum and a relatively large birth canal. Biacetabular breadth is difficult to measure in living people without invasive imaging, which complicates understanding the effect of this "obstetrical dilemma". Proxy measurements, such as bitrochanteric or bicristale breadth, have been used, but how well either of these easily obtainable measurements predicts biacetabular breadth remains unknown. Consequently, we examine whether or not biacetabular breadth is predicted by bitrochanteric or bicristale breadth in males and females. Biacetabular breadth, bicristale breadth, bitrochanteric breadth, and left and right femoral head diameters were measured on 154 AP radiographs (from 61 females and 93 males; aged 18 to 65 years) collected from a radiograph database. Multiple linear regression was used to assess the ability of bitrochanteric or bicristale breadth to predict biacetabular breadth. We found that biacetabular breadth is predicted by bitrochanteric breadth in both males (r-squared=0.48) and females (r-squared=0.63). Bicristale breadth predicts less of the variation in biacetabular breadth in males (r-squared=0.13) than in females (r-squared=0.54). Including the effect of both bitrochanteric and bicristale breadth improved the predictive ability in females (r-squared=0.70) but not in males. (All p-values were <0.001). We conclude that bitrochanteric and bicristale breadth predict biacetabular breadth but that greater than 30% of the variability remains unexplained.

The loss of mechanosensory hair cells in the inner ear gives rise to many hearing and balance-related disorders in humans. The permanent loss of these cochlear hair cells can be caused by many factors, including age and noise-related hearing loss, and ototoxic medications. A certain class of antibiotics known as aminoglycosides as well as a number of chemotherapy drugs such as cisplatin have been identified as ototoxic (being toxic to inner ear structures responsible for hearing and balance), with usage resulting in varying levels of temporary or permanent hearing loss and vertigo. Because of the inaccessibility and complexity of the mammalian ear, the zebrafish has emerged as an effective animal model for studying mechanosensory hair cells due to comparable external mechanosensory hair cells clustered along the lateral line of fish. The external location of the hair cells allows for ease of access and imaging of hair cells for large drug library screens for compounds which protect against ototoxic effects. I followed up on a recent drug library screen of bioactive small molecules which produced three possible protectants against neomycin-induced hair cell loss. To characterize their protective qualities, I exposed zebrafish to different dosages of the protectants and neomycin and measured the amount of hair cell loss to create dose-response profiles for each protectant. Higher protectant doses will increasingly attenuate neomycin-induced hair cell loss. The six tested compounds’ efficacy will be compared to a known protectant compound to see whether they can be further investigated to as a potential ototoxicity-blocking compound (blocking the effects of ototoxicity). The results of this study will identify and describe the efficacy of these putative hair cell protectants and will lead to a better understanding of the role these compounds may play in reducing the effects of ototoxins.