Tag: Poster 84

Hip Joint Moment during Obstacle Crossing Following Concussion in Adolescents

Presenter: Austin Thompson

Co-Presenters: Quinn Peterson, David Howell, Li-Shan Chou

Faculty Mentor: Li-Shan Chou, Quinn Peterson

Presentation Type: Poster 84

Primary Research Area: Science

Major: Human Physiology

Patients with concussion often complain of instability while walking. Previous studies have shown that subjects with concussion have altered gait under normal conditions, dual-task walking, and obstacle crossing. While other studies have looked at joint moments in healthy adolescents and the geriatric population and found that older adults have increased hip moment compared to young adults, there has not been a study looking at the changes in joint moment during obstacle crossing in subjects with concussion. The purpose of this study was to determine the effect of concussion on hip joint moment during obstacle crossing in adolescents. It was hypothesized that peak
hip joint moment of the leading and trailing limbs would be increased in patients with concussion. Nine patients with concussion diagnosed by health professionals were matched with eight control subjects by age, height, mass, sex, and sport. Subjects were tested five subsequent times: 72hrs, 1wk, 2wks, 1mo, and 2mo. Twenty-nine retro- reflective markers were placed on boney landmarks, and motion analysis was performed using a 10 camera, 60 Hz system. The subjects stepped over an obstacle 10% of body height during steady state gait, and data was analyzed using Orthotrakä. The neurometabolic cascade of concussion causes changes to motor control, which could lead to unnecessary strain and a mechanism of further injury while providing further insight into how concussions affect gait.

Engrailed (En) Determines the Morphology of Neurons from Neuroblasts (NB) Lineages of the Ventral Nerve Cord (VNC) in Drosophila

Presenter(s): Claire Bui − Human Physiology

Faculty Mentor(s): Sonia Sen

Poster 84

Research Area: Natural Science

Funding: National Institutes of Health (NIH)

In Drosophila, neuroblasts (NBs) give rise to neurons and glia that make up the central nervous system (CNS). Each NB is characterized by a unique set of molecular markers that are dependent on spatial patterning cues. Spatial pattern is the position of the NB, which determine its cell fate. These patterning cues are crucial for the structure and function of the NBs within cell lineage, the generation of neural diversity, and the proper functioning of the CNS. Previous studies have shown that the transcription factors (TFs) Gooseberry (Gsb) and Engrailed (En) regulate cell fate of neuroblast progeny within the cell lineage. The activation of the Gsb gene has been shown to specify NB 5-6 cell lineage. In contrast, the En gene is expressed in different NBs: 7-1 and 7-4. My research focuses on two different NB cell lineages (5-6, 7-4) and two spatial TF (Gsb & En). En is normally not expressed in 5-6, so I have expressed it in NB 5-6 to see if it is transformed into 7-1 or 7-4. In this experiment, we used molecular markers to quantify NB and neuronal identity at early and late stages of Drosophila embryos. Our data suggested En caused a down-regulation of molecular markers specific to NBs 5-6 and changed the overall morphology of the cell lineage. These findings suggest En regulates the identity of neuronal progeny and provide critical insights into the spatial pattern as a mechanism of generating neuronal morphology.

Effect of Root Symbionts on Inga laurina (Fabaceae) in Disturbed Tropical Forests

Presenter(s): Charles Paulino

Faculty Mentor(s): Krista McGuire & Stephanie Ostresh

Poster 84

Session: Social Sciences & Humanities

Succession in tropical forests is an important yet poorly understood topic in ecology. Dynamic principles are at play that are dictated by resource availability, inter and intraspecific competition, and environmental conditions at affect community structure and function. In this experiment I aim to investigate the physiochemical outputs of Inga laurina(Sw.) Willd., a mid-successional tree, in both early and mid-successional forest plots using Carbon-Nitrogen analysis. Since the roots of I. laurna can be colonized by arbuscular mycorrhizal (AM) fungi andnitrogen- fixing Rhizobium sp. bacteria, I hypothesize: H1: net Nitrogen output into the environment will be higher in the early-successional plot than the mid-successional plot where environmental conditions favor N-fixing bacteria; H2: if H1 is true, than AM fungal root colonization will be higher in mid-successional stage than early-succession, where environmental conditions are favorable for fungal symbionts.