Laboratory and Basic Science Research Commons^™

Microplastics In Local Communities’ Tap Water, Zachary T. Rattell

Masters Theses

Microplastics are an emerging environmental contaminant. One of the ways microplastics can get into the environment is by the breakdown of larger plastics. These plastics can come from industrial practices, discarded fabrics, agriculture, and general plastic waste. As these plastics are broken down microplastics leach into the environment. The widespread use of plastics has resulted in the spread of microplastic contaminants all over the world. Microplastics have been reported to be in drinking water, so this paper is looking at the presence of microplastics in local communities of different demographics and socioeconomic statuses. In other studies of different drinking water …

Stretch Activation During Fatigue Improves Relative Force Production In Fast-Contracting Mouse Skeletal Muscle Fibers, Philip C. Woods

Masters Theses

Stretch activation (F_SA) is the delayed increase in fiber specific tension (force per cross-sectional area) following a rapid stretch and can improve muscle performance during repetitive cyclical contractions. Historically considered minimal in skeletal muscle, our recent work showed the ratio ofstretch- to calcium-activated specific tension (F_SA/F₀) increased from 10 to 40% with greater inorganic phosphate (Pi) levels in soleus muscle fibers (Straight et al., 2019). Given Pi increases with muscle fatigue, we hypothesize that F_SA helps maintain force generation during fatigue. To test this, F_SA, induced by a stretch of 0.5% …

Reproducibility Of Alkaline Inorganic Phosphate Quantification Using 31p-Magnetic Resonance Spectroscopy At 3t, Alexs A. Matias

Masters Theses

INTRODUCTION: The detection of a second inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (31P- MRS) at 3T is technically challenging, which may prevent its reproducible quantification. PURPOSE: To determine the reproducibility of resting alkaline inorganic phosphate (Pialk) measurement using 31P-MRS in human skeletal muscle at 3 tesla (T). METHODS: Resting 31P- MRS of the quadriceps muscles was acquired on two separate visits, within seven days, in 13 healthy, sedentary to moderately active young adults using a whole-body 3T MR system. Measurement variability related to coil position, shimming procedure, and spectral …

Mechanisms And Mitigation Of Skeletal Muscle Fatigue In Single Fibers From Older Adults, Aurora Foster

Masters Theses

Skeletal muscle fatigue is the contraction-induced decline in whole muscle force or power, and can be greater in older versus young adults. Fatigue primarily results from increased metabolism elevating phosphate (P_i) and hydrogen (H⁺), which alters myosin-actin interactions; however, which steps of the myosin-actin cross-bridge cycle are changed and their reversibility are unclear. PURPOSE: This study sought to: 1) Examine the effects of elevated P_i and H⁺ on molecular and cellular function, and 2) Test the ability of deoxyadenosine triphosphate (dATP), an alternative energy to adenosine triphosphate (ATP), to reverse the contractile changes induced …

Developmental Exposure To Xenoestrogens: Effects On The Mouse Mammary Gland Development And Response To Estrogen, Durga Kolla

Masters Theses

Humans experience ubiquitous exposures to estrogenic environmental chemicals from food, personal care products, and other industrial and consumer goods. Bisphenol A (BPA), a well-studied xenoestrogen, is known to alter development of estrogen-sensitive organs including the brain, reproductive tract, and mammary gland. Bisphenol S (BPS), which has a similar chemical structure to BPA, is also used in many consumer products, but its effects on estrogen-sensitive organs in mammals has not been thoroughly examined. In our study, pregnant CD-1 mice were orally exposed to BPS or ethinyl estradiol (EE2, a positive control for estrogenicity) from gestational day 9 through postnatal day (PND) …

Inter-Segment Coordination Variability Post Anterior Cruciate Ligament Reconstruction, Devin K. Kelly

Masters Theses

INTER-SEGMENT COORDINATION VARIABILITY POST ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

SEPTEMBER 2015

DEVIN K. KELLY, B.S., UNIVERSITY OF MASSACHUSETTS AMHERST

M.S., UNIVERSITY OF MASSACHUSETTS AMHERST

Directed by: Dr. Joseph Hamill

There is an increased risk for ipsilateral graft rupture and contralateral ACL rupture following ACL reconstruction surgery (ACLR) despite return to sport clearance. The reason for this increased risk is not well understood. Previous literature has shown that decreased coordination variability is indicative of an injured system regardless of the absence of pain. PURPOSE: To quantify inter-segment coordination variability during three portions of the stance phase of gait in athletes at three …

Rnai Mediated Silencing Of Cell Wall Invertase Inhibitors To Increase Sucrose Allocation To Sink Tissues In Transgenic Camelina Sativa Engineered With A Carbon Concentrating Mechanism, Joshua Zuber

Masters Theses

Plant invertases are a class of proteins that have enzymatic function in cleaving sucrose to fructose and glucose. Cell wall invertase, located on the exterior of the cell wall of plant cells, plays a key role in the unloading of sucrose from the apoplast to the sink tissues. Cell wall invertase interacts with an inhibitor, cell wall invertase inhibitor, post-transcriptionally to regulate its activity. The inhibitor is constitutively expressed in pollen development, early developing seeds, and senescing leaves: indicative of sucrose allocation being a limiting factor at these stages of development. We introduced algal bicarbonate transporters LCIA/CCP1 to Camelina sativa …