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Quantification Of Neuronal Specific Responses To Depletion Of The Nascent Polypeptide-Associated Complex In Caenorhabditis Elegans, Harrison Hall Dec 2019

Quantification Of Neuronal Specific Responses To Depletion Of The Nascent Polypeptide-Associated Complex In Caenorhabditis Elegans, Harrison Hall

Senior Honors Projects, 2010-2019

Cells experiencing misfolded protein stress can become debilitated and die, consistent with this stress being linked to numerous diseases. When misfolded proteins accumulate in the endoplasmic reticulum (ER), the unfolded protein response (UPR) initiates mechanisms that resolve this stress or trigger apoptosis, dependent on the severity and/or duration of the stress. The nascent polypeptide-associated complex (NAC) is a heterodimeric chaperone that mediates proper protein folding and localization during translation; depletion of the NAC promotes misfolded protein stress in the ER, resulting in the initiation of the UPR in affected cells. The relationship between the NAC and the UPR is not …


Decrypting Female Attractivity In Garter Snakes, Holly Rucker May 2019

Decrypting Female Attractivity In Garter Snakes, Holly Rucker

Senior Honors Projects, 2010-2019

Pheromones are utilized by many species as sexual signals driving mate choice, and pheromone production in vertebrates hinges on sex hormone action. Female red-sided garter snakes (Thamnophis sirtalis parietalis) produce a skin-based sex pheromone used by males for mate detection and selection. Estradiol is necessary for pheromone production, yet the specific mechanisms within the skin are unknown. Central to this is the metabolism of testosterone to estradiol via the enzyme aromatase. It is hypothesized that female garter snakes synthesize estradiol locally in the skin and maintain pheromone production via tissue-specific regulation of aromatase. Further, I hypothesize that female …


A Feasibility Study Of Industrial Hemp On Virginia Commercial Poultry Production, Aaron Sloss May 2019

A Feasibility Study Of Industrial Hemp On Virginia Commercial Poultry Production, Aaron Sloss

Senior Honors Projects, 2010-2019

This project sought to characterize industrial hemp as a potential competitive agricultural commodity for the state of Virginia. Specifically, industrial hempseed was evaluated as a feedstock for the commercial broiler (meat-chickens) industry in Virginia.

Data were gathered to identify both the advantages and disadvantages of industrial hempseed as a nutritional resource for broilers. Key nutritional compositions were identified, quantified, and compared to several common feed ingredients, such as soybean, wheat, corn, and sorghum. Hempseed (whole seed) was found to have a considerably high amino acid content, protein, fiber, and metabolizable energy – making it an attractive alternative to conventional feedstuffs. …


Increasing Food Security: Developing And Testing A Nutrition Education Curriculum For A Mobile Food Pantry, Alexandra Lepecha, Kathleen M. Kraft May 2019

Increasing Food Security: Developing And Testing A Nutrition Education Curriculum For A Mobile Food Pantry, Alexandra Lepecha, Kathleen M. Kraft

Senior Honors Projects, 2010-2019

Background: The Neighborhood Produce Market (NPM) is a food distribution model similar to a mobile food pantry. NPM stakeholders observed a lack of community engagement and familiarity with produce offered.

Project Description: The objective was to develop a nutrition education curriculum for NPM volunteers to better engage families and community members by providing food samples, recipes, and nutrition education. A stakeholder steering committee guided the needs assessment, curriculum development, volunteer training, and pilot test. The curriculum consisted of food safety, cultural considerations, and nutritional information for nine produce items and food tasting procedures and recipes. Seven student volunteers were trained …


Analyzing The Effect Of Apoptotic Mutations On The State Of The Nascent-Polypeptide Associated Complex In Caenorhabditis Elegans, Monica Gerber May 2019

Analyzing The Effect Of Apoptotic Mutations On The State Of The Nascent-Polypeptide Associated Complex In Caenorhabditis Elegans, Monica Gerber

Senior Honors Projects, 2010-2019

Cells experiencing misfolded protein stress can become debilitated and die, contributing to the onset of disease. The nascent polypeptide-associated complex (NAC) is a heterodimeric translational chaperone that protects against misfolded protein stress by mediating proper protein folding and localization during translation. Depletion of this complex results in misfolded protein accumulation in the endoplasmic reticulum (ER). To determine the importance of the NAC to proteostasis, we have previously depleted the complex in C.elegans via RNA interference and observed numerous dose-dependent effects, including apoptosis of neuronal cells and changes in gene expression of hypodermal cells. While we have observed these cell-specific responses …


Investigating The Role Of Integrin Beta 3 In Dendritic Arborization In The Supragranular Developing Cerebral Cortex, Zachary Logan Holley May 2019

Investigating The Role Of Integrin Beta 3 In Dendritic Arborization In The Supragranular Developing Cerebral Cortex, Zachary Logan Holley

Senior Honors Projects, 2010-2019

Integrin subunits have been implicated in axonal and dendritic outgrowth. In particular, a strong positive association has been found between mutations in integrin beta 3 (Itgb3) and autism spectrum disorder, but little is known about neuronal Itgb3 function in vivo. Many forms of autism spectrum disorder are thought to arise from dysfunctional dendritic arborization and synaptic pruning. Global knockout of Itgb3 in mice leads to autistic-like behaviors. Itgb3-/- mice also have reduced callosal volume, a key neuroanatomical correlate of autism. Here, we test the hypothesis that Itgb3 is required for normal dendritic arborization in layer II/III pyramidal …


Detecting The Cold: Do Innexins Function In Cold Nociception?, Rachel Barborek May 2019

Detecting The Cold: Do Innexins Function In Cold Nociception?, Rachel Barborek

Senior Honors Projects, 2010-2019

Nociception is the perception of and response to harmful stimuli. Nociception is essential for minimizing tissue damage, but aberrant nociceptive pathways can result in chronic pain. Chronic pain in the U.S. is commonly managed with wide-acting opioids, and precisely defining the components of nociceptive pathways could uncover novel targets for pain therapies. I hypothesize that the vitally quick process of nociception would utilize electrical synapses because they transmit signals between neurons more quickly than chemical synapses do. This study, therefore, aims to uncover the potential role of the eight Drosophila melanogaster gap junction proteins, the Innexins, in cold nociception. Wild …


Impact Of One Night Sleep Restriction On Autonomic Function And Heart Rate Variability In Recreational Cyclists, Amanda J. Becker Jan 2019

Impact Of One Night Sleep Restriction On Autonomic Function And Heart Rate Variability In Recreational Cyclists, Amanda J. Becker

Senior Honors Projects, 2010-2019

Introduction: Sleep quality has been shown to influence autonomic function. The autonomic nervous system (ANS) responds to stressors by regulating key functions such as heart rate. Autonomic function can be monitored via heart rate variability (HRV). Athletes are prone to poor sleep quality due to psychological and physical stresses of training and competing. Our objective was to investigate the function of the ANS at rest and during exercise following a night of normal sleep (SLP+) and a night of restricted sleep (SLP-).

Methods: Subjects (n=9) completed a familiarization trial and two identical experimental trials under different sleep conditions: SLP- (3-hour …


The One Health Initiative: The Intersection Of Human, Animal, And Environmental Health, Mary Evelyn Pearsall Jan 2019

The One Health Initiative: The Intersection Of Human, Animal, And Environmental Health, Mary Evelyn Pearsall

Senior Honors Projects, 2010-2019

The One Health concept is a global strategy for strengthening interdisciplinary collaborations among health care for humans, animals, and the environment. The purpose of this honors capstone project is to study the One Health Initiative and create a comprehensive thesis on what the initiative is and how it is relevant to different sectors of health. An overview of prevalent zoonotic diseases will be provided including how they are transmitted and their global relevance. Case studies on zoonotic diseases will be used in which the effectivity of a One Health approach can be analyzed. In addition, relevant sections on One Health …


Structure/Function Analysis Of Fega And Fhua In Bradyrhizobium Sp., Alexander James Herd Jan 2019

Structure/Function Analysis Of Fega And Fhua In Bradyrhizobium Sp., Alexander James Herd

Senior Honors Projects, 2010-2019

Bradyrhizobium japonicum is a Gram-negative soil bacterium commonly known for its agriculturally significant mutualistic relationship with soybean. In this symbiosis, the bacteria and plant undergo complex molecular signaling characterized by sent and received signals resulting in the formation of infection threads and root nodules. This research aimed to compare two related bacterial outer membrane proteins, FegA and FhuA, associated with the molecular signaling between the bacteria and plant. Previous work has led to the hypothesis that the N-terminal domain (NTD) of FegA in B. japonicum is needed for a functional symbiosis to occur. Recombinant bacterial strains expressing altered FegA proteins …


Biosemiotics As An Argument For The Recontextualization Of Biological Discoveries: A Critical Analysis Of The Biosemiotic Model Of Marcello Barbieri., Augustus Morrissey Snyder May 2018

Biosemiotics As An Argument For The Recontextualization Of Biological Discoveries: A Critical Analysis Of The Biosemiotic Model Of Marcello Barbieri., Augustus Morrissey Snyder

Senior Honors Projects, 2010-2019

The primary purpose of this project was to investigate and explain the philosophical approach of biosemiotics to understanding living systems in contrast to the current scientific paradigm. Secondary goals were to evaluate the potential merits and relevance of this approach to biology and to introduce such a topic for discussion to biologists in a formal academic setting. My method consisted of critical textual analysis supplemented by analogy and biological examples where appropriate. In general, contemporary biosemiotics argues for a teleologic recontextualization of biological discoveries in practice and education. This is accomplished in a sophisticated fashion through the application and modification …


Antimicrobial Activity Of Novel Cationic Amphiphiles, Melanie Kusakavitch May 2018

Antimicrobial Activity Of Novel Cationic Amphiphiles, Melanie Kusakavitch

Senior Honors Projects, 2010-2019

This project focused on the development of amphiphiles in order to prevent hospital-acquired infections before they have a chance to enter the host, thereby reducing the need for antibiotics. The antibiotic resistance crisis of the 21st century is a dangerous epidemic with global consequences. Therefore, there is a desperate need for novel approaches in antimicrobial research. This would decrease the overall length of stay in hospitals and costs associated with such a stay. In this study, tetracationic amphiphiles with two 12-carbon chains and an aliphatic linker were studied. The MIC value of each amphiphile and strain pair was determined and …


Characterizing Tau In The Nucleus, Shaw Grindle Camphire, Madeline Louise Henwood May 2018

Characterizing Tau In The Nucleus, Shaw Grindle Camphire, Madeline Louise Henwood

Senior Honors Projects, 2010-2019

A hallmark of Alzheimer’s Disease (AD) is the aggregation of hyperphosphorylated tau protein into neurofibrillary tangles. Tau localizes to both the cytoplasm and the nucleus of neuronal cells; however, its nuclear role has not been fully defined. Tau has recently been shown to bind to purine-pyrimidine (R/Y) repeats in DNA and stabilize them into Z-DNA. Evidence from our lab suggests that the binding of tau to R/Y repeats causes transcriptional changes of the NOS1 gene. Six major isoforms of tau exist in neurons. These isoforms fall into two groups, denoted as 3R tau and 4R tau, and are found at …


Evolution Of Bordetella Pertussis Genome May Play A Role In The Increased Rate Of Whooping Cough Cases In The United States, Kevin Loftus May 2018

Evolution Of Bordetella Pertussis Genome May Play A Role In The Increased Rate Of Whooping Cough Cases In The United States, Kevin Loftus

Senior Honors Projects, 2010-2019

Bordetella pertussis is the bacterium responsible for pertussis, a disease commonly referred to as whooping cough. Recently, pertussis has made a resurgence in the U.S. despite high-vaccination coverage. Possible causes of the increased number of pertussis cases include genetic evolution of B. pertussis, increased awareness of the disease, better laboratory diagnostics, and the switch from a whole-cellular (wP) vaccine to an acellular vaccine (aP) in the 1990s. Fortunately, just as B. pertussis is evolving, so is the arsenal of technologies used to understand and combat this pathogenic bacterium. Whole genome sequencing is one technology that helps researchers better understand …


Geospatial Analysis Of Eastern Oyster Habitat And Disease In The Chesapeake Bay, Hannah Bradley May 2018

Geospatial Analysis Of Eastern Oyster Habitat And Disease In The Chesapeake Bay, Hannah Bradley

Senior Honors Projects, 2010-2019

Crassostrea virginica, common name eastern oyster, in the Chesapeake Bay is currently at 1% of its peak annual landings in 1884 (600,000 metric tons). This decline is in spite of being considered a resilient species. Causes of the decline include overharvesting, disease, and habitat loss. While efforts have been made to combat each cause, the key element to recovering the population is coordinated habitat restoration. This study aims to develop a GIS-based habitat model for the eastern oyster in the Chesapeake Bay. The first goal of this study was to determine the water quality parameters necessary for successful oyster …


Validity And Reliability Of The Ymca Submaximal Cycle Test Using An Electrically Braked Ergometer, Justin Kidd May 2018

Validity And Reliability Of The Ymca Submaximal Cycle Test Using An Electrically Braked Ergometer, Justin Kidd

Senior Honors Projects, 2010-2019

Purpose: To test the effect of using an electrically braked ergometer on the validity and reliability of the YMCA submaximal cycle test.

Methods: 22 male and 13 female subjects ages 19 to 31 completed one maximal treadmill test and four submaximal cycle tests to measure and estimate VO2max, respectively. The maximal tests involved recording heart rate and VO2 during graded exercise until volitional fatigue; an actual max was verified when two out of the following criteria: respiratory Exchange Ratio > 1.1, VO2 plateau (< 150 ml/min increase in VO2 during final stage), and achievement of 90% age-predicted HR max (or completed …


Escape Behavior Of The Grammostola Rosea Tarantula And Phidippus Regius Spider In Response To Heat Stimuli, Madison Thomas May 2018

Escape Behavior Of The Grammostola Rosea Tarantula And Phidippus Regius Spider In Response To Heat Stimuli, Madison Thomas

Senior Honors Projects, 2010-2019

Insects respond to aversive stimuli such as wind, looming and heat by escaping in a direction opposite the stimuli. Spiders have 8 legs, which offers the spider more gait options for escape than insects, which have 6 legs. However, there are few published studies on the escape response of spiders, and there is no information that shows how location or direction of the stimulus will affect escape patterns. Therefore, the specific goal of my research was to determine the relationship between the stimulus location and direction of response in two species of spider – Regal Jumping spiders (Phidippus regius …


Contributions Of Aδ Nociceptors To The Nociceptive Withdrawal Response In Intact Unanesthetized Rats, Kristin Sammons May 2018

Contributions Of Aδ Nociceptors To The Nociceptive Withdrawal Response In Intact Unanesthetized Rats, Kristin Sammons

Senior Honors Projects, 2010-2019

The nociceptive withdrawal response (NWR), characterized by rapid withdrawal of stimulated body parts, can be evoked by stimulation of two classes of sensory nociceptors: Aδ and C-fibers. Previous studies revealed conflicting results concerning the factors that determine the direction and magnitude of the NWR. Some studies showed that the direction of the NWR depends upon stimulus location. In contrast, other studies, including those from our laboratory, showed that the direction of the NWR does not depend on stimulus location but rather is modulated by posture. However, it is likely that the heat stimuli delivered in our studies stimulated a mixture …


Identifying A B. Thuringiensis Var. Kurstaki Receptor Binding Protein For Bacteriophage Riley, Rachel Carson May 2018

Identifying A B. Thuringiensis Var. Kurstaki Receptor Binding Protein For Bacteriophage Riley, Rachel Carson

Senior Honors Projects, 2010-2019

With the rapid emergence of antibiotic resistant bacteria affecting people around the world, research into new therapies using bacteriophages (phages) is increasing in the United States. Phages are viruses that can only infect bacteria and are able to co-evolve alongside the bacteria they infect. A researchers’ ability to pinpoint which phage to use in the therapy is important to combat an infection effectively. To do so, the genes that control the interaction between phages and the bacteria they infect, such as receptor binding proteins on the surface of a bacterial cell, need to be identified. Transposon mutagenesis was used in …


Enhancing The Sea-Phages App To Collect Weather-Related Metadata From Soil Sampling Locations, Kelly M. Degnon May 2018

Enhancing The Sea-Phages App To Collect Weather-Related Metadata From Soil Sampling Locations, Kelly M. Degnon

Senior Honors Projects, 2010-2019

The bacteriophage population is extremely diverse and abundant, with a seemingly limitless number of phages that have yet to be isolated and sequenced. The SEA-PHAGES program discovers and completely sequences the genome of hundreds of phages every year, contributing to the ever-growing database of phage sequences. However, there is little data about the conditions in which these phages are collected and if weather conditions can have an effect on the likelihood of isolating a phage. The SEA-PHAGES app, when used by students in the SEA- PHAGES program, will collect data on the location and weather conditions in which a soil …


Antibacterial Properties Of Novel Amphiphiles: Exploring Structure-Activity Relationships, Reafa Hossain May 2018

Antibacterial Properties Of Novel Amphiphiles: Exploring Structure-Activity Relationships, Reafa Hossain

Senior Honors Projects, 2010-2019

The increased cases of antibiotic resistance have large implication in hospital settings where infections by antibiotic resistant bacteria are harder to treat resulting in longer stays at the hospital, which drastically increases the costs to patients and hospitals. To address this matter, many research groups are searching for an alternative to antibiotics. One option is the development of amphiphiles, some of which have antibacterial properties. Amphiphiles contain a hydrophilic, polar head group, and a hydrophobic, nonpolar tail, which may intercalate into the cell membrane, resulting in cell lysis. Understanding the impact of amphiphile geometry on antibacterial activity allows for the …


Sustainable Agriculture: Integration Of Aquaponics At Punta Leona Hotel And Club In Costa Rica, Cailin Sierra Dyer, Paris Riley Smith May 2018

Sustainable Agriculture: Integration Of Aquaponics At Punta Leona Hotel And Club In Costa Rica, Cailin Sierra Dyer, Paris Riley Smith

Senior Honors Projects, 2010-2019

Sustainable agriculture is becoming an increasingly important method of food production. As human populations continue to grow, attendant food demand has been increasingly met via agribusiness, including monoculture crop production and factory farming. As is well documented, the rise of agribusiness has led to resource degradation and declining stocks on which “sustainable agriculture” relies. This paper describes a local attempt to re-establish “sustainable agriculture” through the development of an aquaculture system that mimics a naturally occurring cycle that integrates fish and plants. The system was constructed over a three-week period in Punta Leona, Costa Rica. First, the ground was cleared …


Searching For Potential Binding Partners Of Arabidopsis Β-Amylase9 Using Yeast 2-Hybridization, Sheikh Hossain May 2018

Searching For Potential Binding Partners Of Arabidopsis Β-Amylase9 Using Yeast 2-Hybridization, Sheikh Hossain

Senior Honors Projects, 2010-2019

In plants, starch is a major carbon and energy storage compound. Starch is made as a product of photosynthesis while plants are in light and is degraded at night. Our lab is interested in the cellular mechanism of starch degradation in plants and for our studies we use Arabidopsis thaliana as a model. β-amylases are primarily responsible for the hydrolysis of starch in plants and a total of nine β-amylases genes are encoded in Arabidopsis thaliana. These nine genes are identified as BAM1-9. BAM9 is located in the chloroplast where starch is located, and is present …


Muscle Synergies And How They Contribute To The Movement Of The Tail During The Nociceptive Withdrawal Response In The Rat’S Tail, Hasti Izadpanah May 2018

Muscle Synergies And How They Contribute To The Movement Of The Tail During The Nociceptive Withdrawal Response In The Rat’S Tail, Hasti Izadpanah

Senior Honors Projects, 2010-2019

Noxious stimuli can evoke the nociceptive withdrawal response (NWR), which protects the affected part of the body from injury. The rat’s tail, because of the large number of joint (n=84) and muscle (n=300) degrees of freedom, may present a computational challenge to the central nervous system. Previous studies have revealed that synergies act to reduce the number of degrees of freedom across diverse movements in a variety of animals; however, there is little information in mammals on synergistic control of the tail. The long-term specific aim of this project is to test the hypothesis that during the NWR muscle synergies …


Reconstruction Of The Tail Nociceptive Withdrawal Response From Combinations Of Movement Primitives Associated With Individual Muscles In The Rat, Justin Nguyen May 2018

Reconstruction Of The Tail Nociceptive Withdrawal Response From Combinations Of Movement Primitives Associated With Individual Muscles In The Rat, Justin Nguyen

Senior Honors Projects, 2010-2019

Abstract

One type of involuntary movement is the nociceptive withdrawal response (NWR), in which mammals move a part of their body away from noxious, or tissue damaging, stimuli. Previous studies have evoked the limb NWR in diverse animals such as cats, frogs, and humans. However, there is minimal information on how complex movement arising from numerous muscles and joints, such as in the tail of the rat, is effectively coordinated.

The specific aim was to identify the contribution of movement from individual extrinsic muscles to the tail NWR utilizing a new technique. From previous studies, extrinsic muscles in the pelvis …


Targeting Of Central Nucleus Projections To Extramodular Zones Of The Lateral Cortex Of The Inferior Colliculus In Developing Mouse, Isabel D. Lamb-Echegaray May 2018

Targeting Of Central Nucleus Projections To Extramodular Zones Of The Lateral Cortex Of The Inferior Colliculus In Developing Mouse, Isabel D. Lamb-Echegaray

Senior Honors Projects, 2010-2019

The multimodal lateral cortex of the inferior colliculus (LCIC) exhibits a modular-extramodular micro-organization that is evident early in development. In addition to a set of neurochemical markers that reliably highlight its modular-extramodular organization, mature projection patterns in a variety of adult species suggest that major LCIC afferents also recognize and adhere to such a framework. This patch-matrix-like arrangement appears to segregate into distinct afferent streams, with somatosensory inputs targeting LCIC modules and auditory inputs targeting surrounding extramodular zones. Currently lacking is a detailed understanding of the development and shaping of multimodal LCIC afferents with respect to its modular-extramodular framework. The …


An N-Terminal Acidic Domain In Β-Amylase2 Is Required For K+ Regulation., Jillian Breault May 2018

An N-Terminal Acidic Domain In Β-Amylase2 Is Required For K+ Regulation., Jillian Breault

Senior Honors Projects, 2010-2019

In the chloroplasts of leaf mesophyll cells, β-amylase proteins (BAMs) are responsible for breaking down starch into maltose when the plant cannot undergo photosynthesis. BAM2, which was previously considered inactive, was recently shown to be active under stromal-like levels of salt and has optimal activity at 80mM KCl. In addition, BAM2 is active as a tetramer in vivo and displays sigmoidal kinetics due to a secondary binding site that is responsible for activating BAM2 when bound to starch. A hypothesized tetramer model was created using a homology model of a BAM2 monomer and the configuration of a crystallized sweet potato …


A Cure For Salmonella: Engaging Students In Pathogen Microbiology And Bioinformatics, Sophie Jurgensen Jan 2018

A Cure For Salmonella: Engaging Students In Pathogen Microbiology And Bioinformatics, Sophie Jurgensen

Senior Honors Projects, 2010-2019

Advances in Next Generation Sequencing (NGS) technology have generated a vast amount of publicly available genomic data, creating a need for students with training in computational analysis. This laboratory lesson is a course-based undergraduate research experience (CURE) focusing on environmental Salmonella, a common foodborne pathogen that is of great interest to public health laboratories but is relatively less virulent than most other such pathogens. As discovery is a central tenet of CUREs, students isolate novel Salmonella enterica and related strains from stream sediment, poultry litter, or other sources in the first half of the lesson (Module 1). They also …


Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers Jan 2018

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …


Repeatability Of The Heart Rate Variability Threshold During Treadmill Exercise, Shane Chambers Jan 2018

Repeatability Of The Heart Rate Variability Threshold During Treadmill Exercise, Shane Chambers

Senior Honors Projects, 2010-2019

Purpose: Heart rate variability threshold (HRVT) is a clinical parameter used to gain insight into autonomic balance. Various studies have validated the use of cycle ergometers in determining HRVT, although the literature lacks evidence that treadmill use is a viable means of determining this threshold. We examined the repeatability of HRVT occurrence using standard deviation of normal R-R intervals (SDNN), root mean square of successive differences of continuous R-R intervals (RMSSD), and standard deviation of instantaneous beat intervals (SD1) in college aged males using treadmill exercise to see if this is a reliable method of threshold determination.

Methods: Ten healthy, …