The effect of serration angle on spine puncture mechanics
Spines, defined as rigid biological structures that come to a point, are physical features found across a wide range of organisms; however general relationships between spine structure and function remain unclear. This study explores a specific aspect of the form-function relationship of spines, by investigating the influence of serration angle on spine puncture mechanics. Autodesk Fusion 360 was used to 3D-model spines with differing serration angles, which were then printed out with hard resin. The models will undergo materials testing as they are punctured into and retracted from ballistics gel. The maximum force needed for both puncture and retraction will be recorded and analyzed to see whether a change in serration angle leads to a change in puncture mechanics. Maximum puncture force is expected to increase with serration angle, as serrations angled more towards the front of the spine will increase the surface area on which the ballistics gel can resist the spine’s entry. An inverse trend with maximum retraction force is also expected, as similar gel-spine interactions will occur but in the reverse direction.
*This abstract is the first draft of what will ultimately be used for the poster presentation at the end of this program*
The gut microbiome & depression: what is the best method for DNA extraction?
Our gut microbiomes play an important role in immune functioning, nutrient processing, and regulating many aspects of brain functioning. This gut-brain axis has been implicated in major depressive disorder, and inducing a depressive phenotype in mice using social defeat (SD) is one commonly used model to study the shifts in microbial diversity that occur. To do so, an effective protocol to extract and sequence the bacterial DNA from the fecal matter of subject mice is required. As it stands, methods and results in the field vary widely. This study compared two DNA extraction kits—the Maxwell RSC PureFood GMO & Authentication Kit and the MoBio PowerSoil DNA Isolation Kit. The Promega kit was hypothesized to be superior due to its high degree of automation. In order to assess the quality of the extracted DNA, spectrophotometer, fluorometer and electrophoresis were used. Results from 16S rRNA gene sequencing are awaited for phylogenetic classification of the samples. Analyses indicate that the Promega kit is more efficient, requiring less sample, but may have co-purified contaminants. Sequencing results will indicate effects of this, if any. Further work must explore microbial changes after SD and treatment, and the roles of specific bacterial species on the CNS.
Mild Traumatic Brain Injury (mTBI): Role of rotational kinematics through the mechanism of shear shock
ABSTRACT— Despite decades of research, the exact mechanism in mild Traumatic Brain Injury (mTBI) remains unknown. The purpose of this study was to determine whether rotational velocity or acceleration is the primary contributor to mTBI and explore the effect of shear shock waves generated from rotational acceleration. It was hypothesized that rotational acceleration, not rotational velocity, has a primary role in mTBI, and shear shock waves due to the nonlinear pressure waves are a mechanism for mTBI. This study was conducted with a dual modeling and experimental approach. First, strain and deformation response was observed and recorded through the finite element analysis Simulated Injury Monitor (SIMon model). These results were then compared to deformations and strains recorded during pig brain rotational impacts using three dimensional imaging analysis. So far, the simulations reflect the relatively lower strain and stresses created through rotational velocity. Results indicate that rotational acceleration through the mechanism of shear shock waves is a prevalent mechanism in mTBI and could largely alter how future head injury criterions are created and how protective gears for sports players and the military are crafted.