The Effect of Four Different Stretching Protocols on Muscular Power

This review of literature explores the varying amount of evidence available for different stretching protocols included in the warm-up period. The objective of a comprehensive warm-up is to increase core temperature and improve muscle elasticity to prepare muscles for the demands of activity. Static (held) stretching and dynamic (slow moving) stretching seem to be utilized more often, and they are most studied in the bulk of stretching research. There has been less research published on the effect of ballistic (rapid bouncing movement) stretching. The overwhelming majority of literature has found that when compared, dynamic stretching increases power activity performance significantly more than static stretching. Noticeably, most available research using dynamic stretching protocols actually have a mix of both ballistic and dynamic stretches. The few articles that focused on ballistic-only stretches found conflicting results. Ballistic stretching has a stigma of increasing the chance of injury, due to the bouncing aspect. With the repeated bounce at the end range of motion, it may cause the muscle to be overstretched. The available research shows that the extra bounce has aided in increasing flexibility, while not increasing the chance of injury. With ballistic stretching being safe to perform, there is a need for more research to determine if dynamic-only or ballistic-only stretching has the greater effect on power performance

Exploring the mechanism of SHP2 and EGFR/HER2 cooperation in breast cancer cell signaling

The Src homology 2-containing protein tyrosine phosphatase 2 (SHP2) has been established as a critical mediator of cancer-related cell signaling downstream of receptor tyrosine kinases like EGFR and HER2. As such, targeting of SHP2 is being recognized as a potentially viable therapeutic option in HER2-positive and triple-negative breast cancers. In this report, I employed molecular and cellular biology techniques to further elucidate the role of SHP2 downstream of receptor tyrosine kinases in breast cancer cell lines. In this way, I was able to contribute knowledge to how SHP2 controls triple-negative cell motility. In addition, the mechanism of SHP2 control of HER2 signaling was investigated in order to better understand how SHP2 positively mediates signaling. The EGFR/HER2 heterodimerization axis was also explored, uncovering a mechanism by which HER2 is able to protect EGFR from degradation through suppression of phosphorylation at specific sites. Finally, molecular modeling was used to determine how SHP2 is able to selectively interact with endogenous substrates. These studies contribute both to the rationale for targeting SHP2 and the mechanism by which SHP2 promotes breast cancer signaling in cooperation with EGFR and HER2. The knowledge added by these studies will hopefully contribute in the future toward the development of selective small molecule inhibitors of SHP2

Vetting the Lobster Diagram: Searching for Unseen Companions in Wide Binaries using NASA Space Exoplanet Missions

Over the past decade, the number of known wide binary systems has exponentially expanded thanks to the release of data from the Gaia Mission. Some of these wide binary systems are actually higher-order multiples, where one of the components is an unresolved binary itself. One way to search for these systems is by identifying overluminous components in the systems. In this study, we examine 4947 K+K wide binary pairs from the SUPERWIDE catalog and quantify the relative color and luminosity of the components to find evidence for additional, unresolved companions. The method is best illustrated in a graph we call the "Lobster diagram." To confirm that the identified overluminous components are close binary systems, we cross-match our wide binaries with the TESS, K2 and Kepler archives and search for the signs of eclipses and fast stellar rotation modulation in the light curves. We find that $78.9\%\pm20.7\%$ of the wide binaries which contain an eclipsing system are identified to be overluminous in the "Lobster Diagram" and $73.5\%\pm12.4\%$ of the wide binaries which contain a component showing fast rotation ($P<5$) days also show an overluminous component. From these results, we calculate a revised lower limit on the higher-order multiplicity fraction for K+K wide binaries of $40.0\%\pm1.6\%$. We also examine the higher-order multiplicity fraction as a function of projected physical separation and metallicity. The fraction is unusually constant as a function of projected physical separation while we see no statistically significant evidence that the fraction varies with metallicity.Comment: Submitted and accepted to Ap

Looking for the dM in sdB+dM Systems

Arts and Sciences Undergraduate Research ScholarshipWe report eclipse timings and optical/infrared photometry of a sample of binary stars that include low-mass, nondegenerate stars, some of which are post-common envelope (PCE) secondary companions to hot subdwarf B (sdB) stars. We model the reflection effect in the later systems to characterize the temperature of the heated hemisphere of the secondaries, first from blackbody fits and then by comparison to libraries of the spectral energy distribution of dwarf M stars. We explore how consistent our phenomenological results are with the properties inferred from analysis of light curve shapes. Currently, the masses of these low-mass stars are unknown. We discuss the prospects for turning these reflection effect systems into double-lined spectroscopic binaries for characterization of the mass-radius relationship of low-mass PCE secondaries.Ohio State College of Arts and SciencesNo embargoAcademic Major: Astronomy and Astrophysic

Analysis of phosphatases in ER-negative breast cancers identifies DUSP4 as a critical regulator of growth and invasion.

Estrogen receptor (ER)-negative cancers have a poor prognosis, and few targeted therapies are available for their treatment. Our previous analyses have identified potential kinase targets critical for the growth of ER-negative, progesterone receptor (PR)-negative and HER2-negative, or "triple-negative" breast cancer (TNBC). Because phosphatases regulate the function of kinase signaling pathways, in this study, we investigated whether phosphatases are also differentially expressed in ER-negative compared to those in ER-positive breast cancers. We compared RNA expression in 98 human breast cancers (56 ER-positive and 42 ER-negative) to identify phosphatases differentially expressed in ER-negative compared to those in ER-positive breast cancers. We then examined the effects of one selected phosphatase, dual specificity phosphatase 4 (DUSP4), on proliferation, cell growth, migration and invasion, and on signaling pathways using protein microarray analyses of 172 proteins, including phosphoproteins. We identified 48 phosphatase genes are significantly differentially expressed in ER-negative compared to those in ER-positive breast tumors. We discovered that 31 phosphatases were more highly expressed, while 11 were underexpressed specifically in ER-negative breast cancers. The DUSP4 gene is underexpressed in ER-negative breast cancer and is deleted in approximately 50&nbsp;% of breast cancers. Induced DUSP4 expression suppresses both in vitro and in vivo growths of breast cancer cells. Our studies show that induced DUSP4 expression blocks the cell cycle at the G1/S checkpoint; inhibits ERK1/2, p38, JNK1, RB, and NFkB p65 phosphorylation; and inhibits invasiveness of TNBC cells. These results suggest that that DUSP4 is a critical regulator of the growth and invasion of triple-negative breast cancer cells

Panama Bridge Project

The Panama Bridge project has partnered with Rio Missions Panama to design a bridge for the village of La Gigi, Panama. The mountain community of La Gigi experiences heavy rainfall during the rainy seasons. A stream runs along the community, separating locals from their fields and other communities further up the mountain. While passable during dry seasons, the stream floods and becomes impassable after heavy rains. The residents are effectively cut off from their livelihoods, church, health services, and other communities during this time. To accommodate this need, the Panama Bridge Team has spent the 2019-2020 school year designing an aluminum truss bridge, spanning 90 feet. The design includes a unique construction strategy to deal with challenging site constraints.https://mosaic.messiah.edu/engr2020/1020/thumbnail.jp

HST/FGS Trigonometric Parallaxes of M-dwarf Eclipsing Binaries

Hubble Space Telescope (HST) Fine Guidance Sensor (FGS) trigonometric parallax observations were obtained to directly determine distances to five nearby M-dwarf/M-dwarf eclipsing binary systems. These systems are intrinsically interesting as benchmark systems for establishing basic physical parameters for low-mass stars, such as luminosity L, and radius R. HST/FGS distances are also one of the few direct checks on Gaia trigonometric parallaxes, given the comparable sensitivity in both magnitude limit and determination of parallactic angles. A spectral energy distribution (SED) fit of each system's blended flux output was carried out, allowing for estimation of the bolometric flux from the primary and secondary components of each system. From the stellar M, L, and R values, the low-mass star relationships between L and M, and R and M, are compared against idealized expectations for such stars. An examination on the inclusion of these close M-dwarf/M-dwarf pairs in higher-order common proper motion (CPM) pairs is analyzed; each of the 5 systems has indications of being part of a CPM system. Unexpected distances on interesting objects found within the grid of parallactic reference stars are also presented, including a nearby M dwarf and a white dwarf