Biology Commons^™

Unraveling The Neurogenin/Ngn-1 Gene Regulatory Network Of C. Elegans Using Classical Genetics And Comparative Transcriptomics, Elyse Christensen

Master of Science in Integrative Biology Theses

Proper nervous system development is required for an organism’s survival and function. Defects in neurogenesis have been linked to neurodevelopmental disorders such as schizophrenia and autism spectrum disorders. Understanding the gene regulatory networks that orchestrate neural development, specifically cascades of proneural transcription factors, can better elucidate which genes are most essential in governing early neurogenesis. Neurogenins are a family of such factors that are both sufficient and necessary for the development of neural sub-types in mice, primarily through the regulation of other factors, particularly NeuroD. The objective of this study was to evaluate previously established regulatory targets of neurogenin(ngn-1 …

Neural Development To Neurodegeneration Through The Mind Of A Worm, Miranda Arnold

Master of Science in Integrative Biology Theses

Defects in the nervous system can impact the normal function of an organism. By examining mutations during neuronal development, we can better understand the significance of specific pathways. The EphR/ephrin pathway is crucial for axonal guidance during development. The simple organism, C. elegans, allow us to study the impact of EphR/ephrin genes on neuronal morphology, synapse connections, and basic behavior. In specific EphR/ephrin mutants, we see change in morphology and loss of synapses in a thermosensory and also a chemosensory circuit. These mutations can also lead to defects in food searching behaviors. These observations lead us to conclude that …

Molecular Detection Of Pathogenic Leptospira Throughout The Caribbean, Zamara R. Garcia Truitt

Biology Theses

Leptospirosis is a common widespread zoonotic disease found throughout the Caribbean. The infection is produced by a pathogenic Leptospira species found in tropical and subtropical regions. The severity of the disease ranges from a mild asymptomatic infection to death. Leptospirosis is a neglected tropical disease due to the lack of public awareness and health approaches. Therefore, misdiagnosis is common because the symptoms are similar to that of other tropical endemic diseases. The aim of the study was to determine the presence of pathogenic Leptospira in water samples collected from Puerto Rico and Trinidad. Sixty-four environmental water samples were collected throughout …

The Developmental And Behavioral Effects Of Δ9-Tetrahydrocannabinol On A Spastic Mutant, Victoria Mendiola

Master of Science in Integrative Biology Theses

Hyperekplexia is a neurological disorder affecting infants and can be characterized by excessive startle reactions in response to unexpected stimuli. This disease can be modeled in zebrafish in the bandoneon (beo) mutant, where the glrbbmutation results in glycine receptor (GLYR) loss of function glycine receptors and ultimately, improper inhibitory signaling. Though hyperekplexia is a glycinergic-based signaling disorder, disease symptoms are often alleviated with GABA-agonistic benzodiazepines. Exogenous cannabinoids also modulate GABAergic signaling, and THC, one of the natural compounds that prompted the discovery of the endocannabinoid system mimics the effects of endogenous cannabinoids at endocannabinoid and non-cannabinoid sites in the …

Delivering Signal-Altering Bacterial Effector Proteins To Mammalian Cells Using Cell-Penetrating Peptide Technology, Robert Dickson

Master of Science in Integrative Biology Theses

A major role of the mitogen activated protein kinase (MAPK) pathway in eukaryotes is to activate the bacterial pathogen defense response upon the detection of bacterial products in the environment. This defensive signaling results in the induction of inflammation, the transcription of antimicrobial peptides, the modulation of the cell cycle and cell survival. Some Gram-negative bacteria have evolved needle-like structures called Type III Secretion Systems (T3SS) that secrete signal-altering molecules into the host cell to interrupt signaling pathways that would otherwise lead to the elimination of the bacterial infection. These signal-altering molecules are known as bacterial effector proteins (BEPs). Bacterial …

Solanum Plastisexum, An Enigmatic New Bush Tomato From The Australian Monsoon Tropics Exhibiting Breeding System Fluidity., Angela J. Mcdonnell, Heather B. Wetreich, Jason T. Cantley, Peter Jobson, Christopher T. Martine

Faculty Journal Articles

A bush tomato that has evaded classification by solanologists for decades has been identified and is described as a new species belonging to the Australian “Solanum dioicum group” of the Ord Victoria Plain biogeographic region in the monsoon tropics of the Northern Territory. Although now recognised to be andromonoecious, S. plastisexum Martine & McDonnell, sp. nov. exhibits multiple reproductive phenotypes, with solitary perfect flowers, a few staminate flowers or with cymes composed of a basal hermaphrodite and an extended rachis of several to many staminate flowers. When in fruit, the distal rachis may abcise and drop. A member of …

Hawk On Wire: Ecopoems By Scott T. Starbuck, Vivian M. Hansen

The Goose

Review of Scott T. Starbuck’s Hawk on Wire: Ecopoems

The Development Of Diving Capabilities In Weddell Seal (Leptonychotes Weddellii) Pups Throughout Early Ontogeny, Emma Weitzner

Master's Theses

Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to …

Comparison Of An Electron Transport System (Ets) Enzyme-Mediated Reduction Assay And Respiration Rate Of The Invasive Copepod Eurytemora Carolleeae In Green Bay, Wi, Usa, Alexander Timpe

Lawrence University Honors Projects

The use of aquatic resources for agriculture, trade, and recreation adds stress to water-dwelling organisms. Rapid changes in abiotic conditions, such as warming due to climate change and nutrient loading from agricultural runoff and urban areas, threaten to induce profound alterations to aquatic environments. These changes affect interspecific community interactions and may cause an aquatic resource to lose its functionality that is valuable to humans. Studying organisms such as plankton that form an ecosystem’s foundation is an important step towards understanding the entire food web and predicting how it may or may not be able to respond to a changing …

Understanding How Map Kinases Influence Endothelial Nitric-Oxide Synthase Activity, Xzaviar Solone

Master of Science in Integrative Biology Theses

Mitogen activated protein kinases (MAPK) p38 and ERK have both been reported to bind endothelial nitric oxide synthase (eNOS) with submicromolar affinity via proposed interactions with a pentabasic non-canonical MAPK binding sequence in the autoinhibitory insertion of eNOS. The neuronal isoform, which lacks the pentabasic motif, did not bind either MAPK significantly. In the present study, the pentabasic motif was validated using predictive modeling programming, and eNOS phosphorylation by MAPKs (P38, ERK and JNK) was examined using in vitro kinase assays and immunoblotting. JNK phosphorylation at Ser¹¹⁴ contrasts with ERK, which phosphorylated Ser⁶⁰⁰, and p38, which phosphorylated …

Play Behavior And The Development Of Boldness And Caution In Juvenile Belding’S Ground Squirrels (Urocitellus Beldingi), Madelene Shehan

Master's Theses

The ubiquity of play among juvenile mammals suggests it provides adaptive benefits, potentially through influences on the development of temperament in young animals. Juvenile Belding’s ground squirrels (Urocitellus beldingi) must balance competing demands for boldness and caution imposed by the fundamental trade-off between their short active season and their vulnerability to predation. In this study, I evaluated whether play helps to facilitate the development of an appropriate balance between boldness and caution in juvenile U. beldingi.I observed the play behavior of juvenile U. beldingiand conducted flight-initiation distance tests to measure boldness-caution at the beginning and toward …

Jet Lag: What’S Light Got To Do With It?, Melissa Richardson

Adventist Human-Subject Researchers Association

Jet lag results in memory loss and sleepiness. Current treatments for jet lag focus on symptoms and not the cause of jet lag; disrupted light environment. This study in mice, uncovered mechanisms of how light regulates jet lag recovery and memory. This work informs our future studies in humans.

Stress And Body Composition Of Juvenile Alligator Snapping Turtles (Macrochelys Temminckii), Brandon Scott Tappmeyer

Graduate Theses/Dissertations

The alligator snapping turtle (Macrochelys temminckii), is a species of conservation concern that is the subject of multiple head-start and reintroduction efforts across its range. In captive propagation programs, producing offspring that are in optimal physiological condition maximizes the likelihood of success after release. The purpose of my study was to compare stress and body composition between one free-ranging reintroduced population and two captive populations. The two captive populations were both housed in southern Oklahoma, but one group was reared indoors whereas the other inhabited outdoor ponds at a national fish hatchery. I used circulating glucocorticoid (corticosterone) concentrations as an …

The Role Of Reactive Oxygen Species In Crotalus Atrox Venom-Induced Cell Death, Lindsay Brown

Master of Science in Integrative Biology Theses

Venomous snake bites impact humans all around the world. Anti-venom treatments mitigate systemic effects such as vascular hemorrhage, platelet aggregation inhibition, and the activation of inflammatory mediators. However, hemorrhagic snake venom also causes a loss of cellular adhesion to extracellular matrix components resulting in massive local tissue damage. To better understand the mechanism in which venom induces local tissue damage, human embryonic kidney cells (HEKS) were grown on PEI then stimulated with 500μg/ml Crotalus atrox (CA) venom for 4 and 10 hours. Alamar Blue assays were used to measure cell viability and results suggest a 15±8.6% (p<0.05) and 59±10.7% (p<0.05) reduction in cell viability at 4 and 10 hours, respectively. Cells stimulated with 500μg/ml venom for 10 hours stained 98±2.2% (p<0.05) positive for Trypan blue, suggesting the venom reduces membrane integrity. Identical treatment in the presence of 200 units PEG-catalase (PC) increased viability by 37±5.7% (p>0.001) compared to …

Fungi In A Hot, Dry, Changing World, Miriam I. Hutchinson

Biology ETDs

My doctoral work focused on understanding the reciprocal relationship between fungi and their environment, namely how fungi respond to environmental flux, as well as how fungi can modify and structure their habitats, especially in the context of climate change. As such, I aimed my research on fungi with distinct adaptations to their environmental niches: endophytic fungi that inhabit plant tissue and thermophilic fungi that are capable of growing at the upper temperature limit for eukaryotic life. My research consisted of three studies. First, I investigated the thermophilic species Myceliophthora heterothallica to demonstrate its use as a model organism for efficient …

Development Of A Long-Acting Nanoformulation Of Dolutegravir For Prevention And Treatment Of Hiv-1 Infection, Brady Sillman

Theses & Dissertations

Dolutegravir (DTG) is a potent human immunodeficiency virus type 1 (HIV-1) integrase strand-transfer inhibitor (INSTI) with a high barrier to viral drug resistance. However, opportunities to improve its profile abound. These include extending the drug’s apparent half-life, increasing penetrance to “putative” viral reservoirs, and reducing inherent toxicities. These highlight, in part, the need for long-acting, slow effective release antiretroviral therapy (LASER ART) delivery schemes. A long-acting (LA) DTG was made by synthesizing a hydrophobic and lipophilic prodrug encased with poloxamer (P407) surfactant. This modified DTG (MDTG) reduced systemic metabolism and polarity, increased lipophilicity and membrane permeability, improved encapsulation, and formed …

Observations And Applications Of Husbandry Methodologies On A Backyard Poultry Farm In Dangriga, Belize, Bailey Carpenter

Animal Science Undergraduate Honors Theses

This study explores the husbandry methodologies on a backyard poultry farm in Dangriga, Belize, with the purpose of producing a set of guidelines for backyard poultry growers that have limited resources in similar regions. The majority of data collection occurred through survey questions approved by the IRB, necropsies approved by IACUC, and general observations. There has been a steady increase in poultry production in developing regions due to its positive effects on income and relative nutrition. However, due to a lack of accessible communication and education regarding effective and safe poultry production, these operators typically see poor productivity and/or profitability …

Human Anatomy And Physiology I: Course Map With Expected Learning Outcomes, Carlos Liachovitzky

Open Educational Resources

This document contains a list with all the Anatomy and Physiology I expected learning outcomes organized by topics, and grouped into ten units: 1. Introduction to A&P: body plan & organization; 2. Introduction to A&P: homeostasis; 3. The chemical level of organization; 4. Levels of organization: the cellular level of organization; 5. Levels of organization: the tissue level of organization; 6. Support and movement: integumentary system; 7. Support and movement: skeletal system & articulations; 8. Support and movement: muscular system; 9. Regulation, integration, and control: nervous system; 10. Regulation, integration, and control: special senses

Each learning outcome is referred to …

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …

Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner

Electronic Theses and Dissertations

North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) …

Health And Social Disparities Influence Opioid Misuse Among Adult Females Living In Rural Areas, Tequila Porter

Master of Science in Integrative Biology Theses

Since the early 1800s scientists have been working to create the best non-addictive pain medication derived from opium. In the early 1800s morphine was distilled from opium extracted from opium poppy plants (Quinones, 2015). Soon after a chemist invents a synthetic derivative of opium and names it diacetylmorphine (heroin) (Quinones, 2015, (Drugs and Morphine Text, 2018). Heroin originally was a safe cure for morphine addiction. Once this was proven to be false, and as having addictive properties, the government intervened and began initiatives to address the issue. This public crisis quickly grew to what modern scientists and healthcare professionals know …

Trans-Cinnamic Acid-Induced Leaf Expansion Involves An Auxin-Independent Component, Jasmina Kurepa, Jan A. Smalle

Plant and Soil Sciences Faculty Publications

The phenylpropanoid pathway, the source of a large array of compounds with diverse functions, starts with the synthesis of trans-cinnamic acid (t-CA) that is converted by cinnamate-4-hydroxylase (C4H) into p-coumaric acid. We have recently shown that in Arabidopsis, exogenous t-CA promotes leaf growth by increasing cell expansion and that this response requires auxin signaling. We have also shown that cell expansion is increased in C4H loss-of-function mutants. Here we provide further evidence that leaf growth is enhanced by either t-CA or a t-CA derivative that accumulates upstream of C4H. We also show that …

Phylogeny Of The Australian Solanum Dioicum Group Using Seven Nuclear Genes: Testing Symon’S Fruit And Seed Dispersal Hypotheses., Christopher T. Martine, Ingrid E. Jordon-Thaden, Angela J. Mcdonnell, Jason T. Cantley, Daniel S. Hayes, Morgan D. Roche, Emma S. Frawley, Ian S. Gilman, David C. Tank

Faculty Journal Articles

The dioecious and andromonoecious Solanum taxa (the “S. dioicum group”) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed dispersal. We combine field/greenhouse observations and specimen-based study with phylogenetic analysis of seven nuclear regions obtained via a microfluidic PCR-based enrichment strategy and high-throughput sequencing, and present the first species-tree hypothesis for the S. dioicum group. Our results suggest that epizoochorous trample burr seed …

Comparing Feeding Accuracy Between High And Low Predation Trinidad Guppies, Lydia J. Bonnell

Honors College Theses

Efficient feeding accuracy could increase an organism’s survival. Although local adaptation in Trinidad guppies is common, the effects on accuracy are unknown. Guppies were wild caught in 2015 and 2017, filmed while capturing prey. Accuracy wasn’t different within samples but differed across samples, possibly due to the prey types used.

Combating Drug Resistance - Comparison Of The Antibiotic Effect Of Hydrastis Canadensis Extract And Pure Berberine Via Minimum Inhibitory Concentration Assay, William Luke Scott, Timothy D. Trott

Research in Biology

Herbal medicines are a melee of complex organic chemicals, making it difficult to ascertain their direct mechanism of action. In contrast to mainstream pharmaceuticals, it is argued that herbal medicines are effective because of multiple constituents working synergistically. The complexity of herbal medicines may give them advantages over simpler pharmaceuticals in combating antibiotic resistant microbes, but these advantages can be difficult to quantitate. Popular literature frequently espouses the healing properties of herbal medicines, but many of these claims are not scientifically supported. Many gains could be realized in public health and medicine if more research was aimed at validating / …

Impact Of Intrinsic Physiological Factors In The Population Recovery Of Myotis Lucifugus (Little Brown Myotis) From White-Nose Syndrome, Caroline Burke, Caitlin Looney, Alissah Sillah, Christopher Richardson

Lesley University Community of Scholars Day

White-nose Syndrome (WNS) has decimated populations of hibernating bats in the US. In particular, Myotis lucifugus (little brown myotis) has been one of the most affected. We investigated the energetic cost of innate immune response and Pseudogymnoascus destructans (Pd) fungal activity on post-hibernating little brown myotis and the link with the recovery of local populations in New England from WNS. We captured bats at one of each of 4 colonies in Eastern Massachusetts and Southern New Hampshire, consecutively, every 14 days to minimize disturbance to the colony. Blood samples were collected from each bat. Respirometry trials were performed on each …

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …

Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

The past two decades have witnessed significant advances in high-throughput ``omics" technologies such as genomics, proteomics, metabolomics, transcriptomics and radiomics. These technologies have enabled simultaneous measurement of the expression levels of tens of thousands of features from individual patient samples and have generated enormous amounts of data that require analysis and interpretation. One specific area of interest has been in studying the relationship between these features and patient outcomes, such as overall and recurrence-free survival, with the goal of developing a predictive ``omics" profile. Large-scale studies often suffer from the presence of a large fraction of censored observations and potential …

Multiscale Model Of Regional Population Decline In Little Brown Bats Due To White-Nose Syndrome, Andrew M. Kramer, Claire S. Teitelbaum, Ashton Griffin, John M. Drake

Integrative Biology Faculty and Staff Publications

1. The introduced fungal pathogen Pseudogymnoascus destructans is causing decline of several species of bats in North America, with some even at risk of extinction or extirpation. The severity of the epidemic of white-nose syndrome caused by P. destructans has prompted investigation of the transmission and virulence of infection at multiple scales, but linking these scales is necessary to quantify the mechanisms of transmission and assess population-scale declines.
2. We built a model connecting within-hibernaculum disease dynamics of little brown bats to regional-scale dispersal, reproduction, and disease spread, including multiple plausible mechanisms of transmission.
3. We parameterized the model using the approach of …

A Ctenophore (Comb Jelly) Employs Vortex Rebound Dynamics And Outperforms Other Gelatinous Swimmers, Brad J. Gemmell, Sean P. Colin, John H. Costello, Kelly R. Sutherland

Integrative Biology Faculty and Staff Publications

Gelatinous zooplankton exhibit a wide range of propulsive swimming modes. One of the most energetically efficient is the rowing behaviour exhibited by many species of schyphomedusae, which employ vortex interactions to achieve this result. Ctenophores (comb jellies) typically use a slow swimming, cilia-based mode of propulsion. However, species within the genus Ocyropsis have developed an additional propulsive strategy of rowing the lobes, which are normally used for feeding, in order to rapidly escape from predators. In this study, we used high-speed digital particle image velocimetry to examine the kinematics and fluid dynamics of this rarely studied propulsive mechanism. This mechanism …