Biophysics Commons^™

Co-Twin Relationship Quality As A Moderator Of Genetic And Environmental Factors On Urinary Cortisol Levels Among Adult Twins, Joseph A. Schwartz, Scott Jessick, Jessica L. Calvi, Douglas A. Granger

Athletic Performance Research

Previous research has indicated that genetic and environmental factors shape physiological activity. Cortisol levels, in particular, have received significant attention, with studies indicating substantive heritability estimates across various sampling techniques. A related line of research has indicated that genetic and environmental factors that explain variability in cortisol levels may vary across context and experiences by way of gene-environment interactions (G×Es). Despite these findings, a limited number of studies have examined the extent to which interpersonal relationships may operate as a moderator. The current study focused on co-twin relationship quality as a source of moderation, as twins are more likely to …

Adrenocortical Attunement, Reactivity, And Potential Genetic Correlates Among Parent-Daughter Dyads From Low-Income Families, Jennifer Byrd-Craven, Michael M. Criss, Jessica L. Calvi, Lixian Cui, Amanda Baraldi, Amanda Sheffield Morris

Athletic Performance Research

Examining the multitude of influences on the development of adolescent stress responses, especially among low-income families, is a critical and understudied topic in the field. The current study examined cortisol attunement between adolescent girls and parents (mostly mothers) from predominantly low-income, single parent, ethnic minority families before and after an in-laboratory disagreement discussion task. The sample consisted of 118 adolescents (M_age = 13.79 years, 76.3% ethnic minorities, 23.7% European Americans) and primary caregivers (M_age = 40.62 years; Mdn yearly income = $24,000; 43.2% single parents; 50% living below poverty line). We investigated oxytocin receptor (OXTR rs53576) …

The Role Of Conformational Dynamics In Isocyanide Hydratase Catalysis, Medhanjali Dasgupta

Department of Biochemistry: Dissertations, Theses, and Student Research

Post-translational modification of cysteine residues can regulate protein function and is essential for catalysis by cysteine-dependent enzymes. Covalent modifications neutralize charge on the reactive cysteine thiolate anion and thus alter the active site electrostatic environment. Although a vast number of enzymes rely on cysteine modification for function, precisely how altered structural and electrostatic states of cysteine affect protein dynamics, which in turn, affects catalysis, remains poorly understood.

Here we use X-ray crystallography, computer simulations, site directed mutagenesis and enzyme kinetics to characterize how covalent modification of the active site cysteine residue in the enzyme, isocyanide hydratase (ICH), affects the protein …

Changes On Movement Control Of Dart Throwing Under Distance And Target Weight Constraints, Carlos E. Campos, Guilherme M. Lage, Andre G.P. Andrade, Crislaine R. Couto, Suziane P. Santos, Vitor L.S. Profeta, Herbert Ugrinowitsch

Athletic Performance Research

The aim of the study was to verify the effects of dart weight and target distance on kinematic variables of the movement control of the underarm dart throwing task. Four women and one man performed the task of throwing a dart at two horizontal circular targets located at 2m (Nt) and 3m (Ft) away, with two different weights, 22g (Ld) and 44g (Hd). On the first phase of the experiment, the human volunteers performed 200 trials per day during four sessions. On the fifth day, it had 40 more trials in a pseudo random order that were recorded and analysed. …

Preliminary Results On Organization On The Court, Physical And Technical Performance Of Brazilian Professional Futsal Players: Comparison Between Friendly Pre-Season And Official Match, Luiz Henrique Palucci Vieira, Sera N. Doğramaci, Ricardo Augusto Barbieri, Fabio Milioni, Felipe Arruda Moura, Vitor Luiz De Andrade, Guilherme Manna Cesar, Paulo Roberto Pereira Santiago

Athletic Performance Research

The main aim of this study was to verify possible differences between a friendly pre-season match (FM) and an official in-season match (OM) regarding physical, technical, and organizational performances of a professional Brazilian futsal team. Ten professional futsal athletes participated in this study. The matches were monitored with video cameras (30 Hz) and athlete trajectories obtained with automatic tracking. The values obtained for distance covered per minute, percentage of distance covered at moderate intensity, team coverage area, spread, passes, possessions, ball touches and successful passes per minute were greater for the OM than FM. On the contrary, percentage of distance …

Examining The Reliability, Validity And Factor Structure Of The Drs-15 With College Athletes, Leilani Madrigal, Diane L. Gill, Kent M. Eskridge

Athletic Performance Research

Hardiness, comprising feelings of commitment, control and challenge, is most frequently measured with the Dispositional Resiliency Scale (DRS), but little work has been done with the brief 15-item version. To examine the factor structure, reliability, validity, and item functioning for gender invariance of the 15-item DRS with 525 collegiate athletes from a wide range of sports. Convergent and divergent validity were examined through relationships with mental toughness, grit and competitive anxiety. Participants completed measures of mental toughness, optimism, grit, competitive anxiety, and the DRS-15. Confirmatory Factor Analysis revealed a poor fit for the three-factor hardiness model, and subsequent exploratory factor …

Noninvasive Measurement Of Electrical Events Associated With A Single Chlorovirus Infection Of A Microalgal Cell, Seung-Woo Lee, Eun-Hee Lee, Gerhard Thiel, James L. Van Etten, Ravi Saraf

Department of Chemical and Biomolecular Engineering: Faculty Publications

Chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1) contains a viral-encoded K⁺ channel imbedded in its internal membrane, which triggers host plasma membrane depolarization during virus infection. This early stage of infection was monitored at high resolution by recording the cell membrane depolarization of a single Chlorella cell during infection by a single PBCV-1 particle. The measurement was achieved by depositing the cells onto a network of one-dimensional necklaces of Au nanoparticles, which spanned two electrodes 70 μm apart. The nanoparticle necklace array has been shown to behave as a single-electron device at room temperature. The resulting electrochemical field-effect transistor …

Frontal Plane Comparison Between Drop Jump And Vertical Jump: Implications For The Assessment Of Acl Risk Of Injury, Guilherme Manna Cesar, Curtis L. Tomasevicz, Judith M. Burnfield

Athletic Performance Research

The potential to use the vertical jump (VJ) to assess both athletic performance and risk of anterior cruciate ligament (ACL) injury could have widespread clinical implications since VJ is broadly used in high school, university, and professional sport settings. Although drop jump (DJ) and VJ observationally exhibit similar lower extremity mechanics, the extent to which VJ can also be used as screening tool for ACL injury risk has not been assessed. This study evaluated whether individuals exhibit similar knee joint frontal plane kinematic and kinetic patterns when performing VJs compared with DJs. Twenty-eight female collegiate athletes performed DJs and VJs. …

Weight Control Practices Of Division I National Collegiate Athletic Association Athletes, Patrick B. Wilson, Leilani Madrigal, Judith M. Burnfield

Athletic Performance Research

Objectives: Altering body weight can have substantial effects on an athlete’s performance and well-being. Limited information is available describing the weight control practices of Division I National Collegiate Athletic Association (NCAA) athletes.

Methods: Weight control practices data from 188 (138 male and 50 female; 18-23 y) Division I NCAA athletes were analyzed as a part of this cross-sectional, retrospective study. Participants completed questionnaires on weight control practices and weight control nutrition knowledge at the end of their season and were classified into weight-sensitive and less weight-sensitive sports.

Results: A higher proportion of females attempted to lose weight than males among …

Glucose-Fructose Likely Improves Gastrointestinal Comfort And Endurance Running Performance Relative To Glucose-Only, P. B. Wilson, S. J, Ingraham

Athletic Performance Research

This study aimed to determine whether glucose-fructose (GF) ingestion, relative to glucose-only, would alter performance, metabolism, gastrointestinal (GI) symptoms, and psychological affect during prolonged running. On two occasions, 20 runners (14 men) completed a 120-min submaximal run followed by a 4-mile time trial (TT). Participants consumed glucose-only (G) or GF (1.2:1 ratio) beverages, which supplied ~1.3 g/min of carbohydrate. Substrate use, blood lactate, psychological affect [Feeling Scale (FS)], and GI distress were measured. Differences between conditions were assessed using magnitude-based inferential statistics. Participants completed the TT 1.9% (−1.9; −4.2, 0.4) faster with GF, representing a likely benefit. FS ratings were …

Misrepresentation Of Carbohydrate For Exercise: ‘It Is Time To Bust The Myth Of Physical Inactivity And Obesity: You Cannot Outrun A Bad Diet’, Patrick B. Wilson

Athletic Performance Research

The contention from Malhotra et al1 regarding the unimportance of carbohydrate for exercise is misguided. First, the reference they provide is an editorial2 that should not be viewed as high-quality evidence. Several oft-cited exercise studies showing benefits with high-fat diets simultaneously utilized carbohydrate restoration strategies,3 which involves “carbohydrate loading” after a high-fat diet. Thus, the evidence provided does not contradict the established belief that carbohydrate is an important fuel for endurance exercise. Second, the authors’ use of the term “carbohydrate loading” is misleading in this context. No public health organizations advocate a diet containing carbohydrate in amounts used in “carbohydrate …

Removable Shoe Spike System, Alex Adams, Nutech Ventures, Inc.,

Athletic Performance Research

The present system, method and apparatus are adapted for the quick and easy exchange of spikes on athletic shoes. More specifically, the system, apparatus and methods comprise a spike having an opening, an aglet adapted for coupling to the shoe, for example by way of a shoelace, and a coupling head affixed to the aglet which is adapted to couple with the opening on the spike so as to allow a user to quickly and easily replace, remove or install spikes in the athletic shoe. The disclosure thus allows the user to have the tool attached to their shoe at …

Elasticity Of Differentiated And Undifferentiated Human Neuroblastoma Cells Characterized By Atomic Force Microscopy, Shijia Zhao, Alexander B. Stamm, Jeong Soon Lee, Alexei Gruverman, Jung Yul Lim, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Human neuroblastoma (SH-SY5Y) cells, with its ability to differentiate into neurons, have been widely used as the in vitro cell culture model for neuroscience research, especially in studying the pathogenesis of Parkinson’s disease (PD) and developing therapeutic strategies. Cellular elasticity could potentially serve as a biomarker to quantitatively distinguish undifferentiated and differentiated SH-SY5Y cells. The goal of this work is to characterize the retinoic acid (RA) induced alternations of elastic properties of SH-SY5Y cells using atomic force microscopy (AFM). The elasticity was measured at multiple points of a single cell. Results have shown that the differentiation of SH-SY5Y cell led …

A Pilot Study Investigating The Reasons For Playing Through Pain And Injury: Emerging Themes In Men’S And Women’S Collegiate Rugby, Leilani Madrigal, Jamie Robbins, Diane L. Gill, Katherine Wurst

Athletic Performance Research

Collegiate rugby is a competitive, collision sport, yet insufficient empirical evidence exists regarding participants’ perspectives on pain and injury. This study addressed male and female rugby players’ experiences with injury, and their views about playing through pain and injury. Eleven rugby players (five male; six female) competing in USA Rugby’s National College 7’s tournament participated in semi structured interviews, which were recorded, transcribed, and content-analyzed. Two major themes emerged: passion for sport and sport ethic. Passion for sport was composed of (a) love of the sport, (b) meaning of the sport, and (c) desire to be on the field. Sport …

Transformations In Matter And Energy: Student Learning And Inquiry To Inform Teaching, Jenny Dauer

DBER Speaker Series

Learning progressions are descriptions of increasing levels of sophistication of student reasoning about a topic based on empirical evidence. Our learning progression framework about student explanations of carbon-transforming processes (e.g. photosynthesis, cellular respiration) describes how student’s interconnected and mutually supporting ideas and practices are deeply embedded in discourse at all levels of achievement. My research is in two areas: 1) applying the learning progression framework for student explanations of carbon-transforming processes to describe the most productive pathways for student learning, 2) extending the research to student reasoning during inquiry activities about carbon-transforming processes. One finding is that students who consistently …

Functional Studies Of Human Cellular Detoxification Enzymes, Melanie Neely Willis

Department of Biochemistry: Dissertations, Theses, and Student Research

Cellular detoxification allows for the maintenance of cellular homeostasis and prevention of abnormal cell growth by clearing harmful xenobiotics and endobiotics. After oxygenation by phase I enzymes, phase II enzymes such as glucuronosyltransferases and glutathione-s-transferases conjugate a small molecule to the compound, marking it for subsequent export. Many up-stream enzymes are also essential to cellular detoxification by supplying the small compounds for conjugation. These up-stream enzymes include UDP-glucose dehydrogenase, which synthesizes UDP-glucuronate, and glutamate cysteine ligase, which catalyzes the first and rate-limiting step in the synthesis of glutathione.
UDP-glucose dehydrogenase (UGDH) is an important enzyme in human development and in …

Mechanisms Of Decreased Cholesterol Absorption Mediated By Phytosterols In The Intestinal Lumen, Andrew W. Brown

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Phytosterols and their fatty acyl esters have been known for decades to lower LDL cholesterol, making them powerful nutraceuticals in lowering cardiovascular disease risk. The mechanisms by which phytosterols lower cholesterol, though, have been incompletely characterized. Three studies were executed to examine three aspects of cholesterol and phytosterol interactions in the intestinal lumen. In the first study, the ability of pancreatic cholesterol esterase to hydrolyze phytosterol esters was examined. Pancreatic cholesterol esterase hydrolyzed phytosterol esters, but the rate of hydrolysis proved sensitive to the structures of both the sterol and ester components. In the second study, cholesterol micellarization was challenged …

The Water Vapor Conductance Of Squamate Reptilian Eggs: The Influence Of Scaling On Nesting Ecology., Louis A. Somma

Papers in Herpetology

Flexible-shelled eggs of squamate reptiles are strongly influenced by their surrounding microclimate, particularly the hydric conditions of the nest. The eggshell water vapor conductance of an egg can be an indication of its requirement for water from the nest. Ackerman et al. (1985. Physiol. Zool. 58:129-137) have described the scaling relationship for eggshell water vapor conductance (G_H2O) of flexible-shelled reptilian eggs (G_H2O = 981.8M^0.52). This scaling relationship was investigated with water vapor conductance data obtained from 8 species of lizards representing the families Iguanidae (Anolis carolinensis, A. sagrai, Sceloporus woodi, S. virgatus) …