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Investigating Climate Change And Nutrient Pollution Effects On Drupella Rugosa Coral Reef Destruction In Koh-Tao, Thailand, Beatrice Canteri Dec 2024

Investigating Climate Change And Nutrient Pollution Effects On Drupella Rugosa Coral Reef Destruction In Koh-Tao, Thailand, Beatrice Canteri

The Plymouth Student Scientist

The introduction and proliferation of invasive species in coral reef ecosystems play a pivotal role as significant contributors to ecological disturbance. These invasive species pose specific threats to the delicate equilibrium of coral reef health by disrupting nutrient cycling, modifying community structure, applying selective pressure on essential coral species, leading to ecosystem degradation. Embarking on an exploration of ecological intricacies, this study focuses on the invasive coral-feeding snail Drupella rugosa in Koh Tao and aims to explore how environmental variables affect its abundance. Although prior research elucidated the impacts of environmental stressors on coral reef degradation, methodological limitations and gaps …


Assembly Of Ppsu-Oligomers, Mariam Nesterov Dec 2024

Assembly Of Ppsu-Oligomers, Mariam Nesterov

Student Theses and Dissertations

The development of nanostructures for delivering multiple proteins to targeted antibodies has become a promising avenue in biotechnology, driven by advancements in synthetic polymers like poly(propylene sulfone), PPSU. However, the PPSU polymer faces a major limitation - its high insolubility. To address this challenge, this study investigates whether PPSU oligomers can enhance both the solubility and stability of lysozyme, a model protein that is cost-effective and widely accessible. Using dimer, trimer, tetramer, and hexamer configurations, we analyzed the interactions between PPSU oligomer and lysozyme under varying conditions. Our results show that the dimer and trimer are water soluble (no aggregate …


Organ-On-A-Chip Platforms For Drug Development, Cellular Toxicity Assessment, And Disease Modelling, Muhammad Maaz Khurram, Göktürk Ci̇nel, Özlem Yeşi̇l Çeli̇ktaş, Erdal Bedi̇r Dec 2024

Organ-On-A-Chip Platforms For Drug Development, Cellular Toxicity Assessment, And Disease Modelling, Muhammad Maaz Khurram, Göktürk Ci̇nel, Özlem Yeşi̇l Çeli̇ktaş, Erdal Bedi̇r

Turkish Journal of Biology

Organ-on-a-chips (OoCs) or microphysiological platforms are biomimetic systems engineered to mimic organ structures onto microfluidic devices for biomedical research. These microdevices can mimic biological environments that enable cell-cell interactions at a small scale by mimicking 3D in vivo microenvironments outside the body. Thus far, numerous single and multiple OoCs that recapitulate organs have been developed, and they have emerged as forerunners for drug efficacy and cytotoxicity testing. This review explores OoC platforms to portray their versatility in investigating drug safety, efficacy, and toxicity. We also reflect upon the potential of OoCs to effectively demonstrate disease models for probable novel therapeutics, …


Mechanistic Insights Into Cardiac Regeneration And Protection Through Meis Inhibition, Aynura Mammadova, Gali̇p Servet Aslan, Li Mo, Qifang Wu, Sebastian Clauss, Fati̇h Kocabaş Dec 2024

Mechanistic Insights Into Cardiac Regeneration And Protection Through Meis Inhibition, Aynura Mammadova, Gali̇p Servet Aslan, Li Mo, Qifang Wu, Sebastian Clauss, Fati̇h Kocabaş

Turkish Journal of Biology

MEIS1, a member of the TALE-type homeobox gene family, has emerged as a pivotal regulator of cardiomyocyte cell cycle arrest and represents a promising therapeutic target. Our study reveals that inhibition of MEIS1 using two novel small molecules, MEISi-1 and MEISi-2, significantly enhances neonatal cardiomyocyte proliferation and cytokinesis. Specifically, MEISi-1 and MEISi-2 increased the proportion of proliferating cardiomyocytes (Ph3+TnnT cells) upto 4.5 fold and the percentage of cytokinetic cardiomyocytes (AuroraB+TnnT cells) by 2 fold, compared to untreated controls. MEIS1 inhibition resulted in a notable downregulation of MEIS1 target genes and cyclin-dependent kinase inhibitors, demonstrating its effect on key regulatory pathways. …


Chelidonic Acid Abrogates Oxidative Stress And Memory Dysfunction In Experimental Aging Rats, Feri̇de Ni̇hal Si̇nan, Emel Serdaroğlu Kaşikçi, Burcu Çevreli̇ Dec 2024

Chelidonic Acid Abrogates Oxidative Stress And Memory Dysfunction In Experimental Aging Rats, Feri̇de Ni̇hal Si̇nan, Emel Serdaroğlu Kaşikçi, Burcu Çevreli̇

Turkish Journal of Biology

Background/aim: In an aging model established in male Wistar albino rats via the administration of D-galactose (D-gal), the aim of this study was to examine the effects of chelidonic acid on cognitive functioning and the levels of glutathione (GSH), malondialdehyde (MDA), Total antioxidant status (TAS), and brain-derived neurotrophic factor (BDNF).Materials and methods: Thirty-two Wistar albino (three month old) male rats (n = 8) were used. Group 1: Control (C), Group 2: Chelidonic acid (CA) (2 mg/kg oral gavage), Group 3: D-galactose (D-gal) (150 mg/kg, s.c.), Group 4: D-gal (150 mg/kg) + CA (2 mg/kg) (DC). Following an overnight fast, the …


Characterization Of Tfiie-Regulated Genes By Transcriptome Analysis, Serdar Baysal Dec 2024

Characterization Of Tfiie-Regulated Genes By Transcriptome Analysis, Serdar Baysal

Turkish Journal of Biology

Previous studies on GTF2E showed that it has association with certain group of diseases such as colon cancer and trichothiodystrophy but what is the global effect of GTF2E on cellular processes is not widely characterized. In this regard, this study aimed to investigate and characterize the affect of GTF2E on transcription level of genes and identify the cellular processes and diseases associated with GTF2E. The HCT116 cell line was used in the study and transfected at 30 nM concentration with siGTF2E1 or non-target negative siRNA. After 72 hours, cells were harvested and prepared for further analysis. Whole transcriptome analysis was …


Characterizing The Francisella Tularensis Universal Stress Protein, Benjamin Girardo Dec 2024

Characterizing The Francisella Tularensis Universal Stress Protein, Benjamin Girardo

Theses & Dissertations

Francisella tularensis is an extremely virulent pathogen responsible for the zoonotic disease tularemia. F. tularensis employs various defense mechanisms to survive and persist under diverse environmental and host-induced stress conditions. Despite its significance, the full spectrum of stress factors that enable F. tularensis persistence remain inadequately understood. In many bacterial species, universal stress proteins (Usp) play a crucial role in managing adverse conditions. The aim of this study was to elucidate the role of Usp in F. tularensis as a means of clarifying the stress response mechanisms of this pathogen. The F. tularensis Usp is encoded by a single, highly …


The Cumulative Effect Of Ellagic Acid And Carnosic Acid Attenuates Oxidative Events During Diabetic Wound Healing: In Different Applications And On Different Days, Eli̇f Naz Gürsoy, Kanuni̇ Barbaros Balabanli, Fatma Nur Tuğcu Demi̇röz, Şule Coşkun Cevher Dec 2024

The Cumulative Effect Of Ellagic Acid And Carnosic Acid Attenuates Oxidative Events During Diabetic Wound Healing: In Different Applications And On Different Days, Eli̇f Naz Gürsoy, Kanuni̇ Barbaros Balabanli, Fatma Nur Tuğcu Demi̇röz, Şule Coşkun Cevher

Turkish Journal of Biology

Background/aim: The hyperglycemic environment in diabetes disrupts normal wound-healing processes, leading to chronic wounds. This study investigated whether the combination of the phenolic compounds Ellagic acid and Carnosic acid shows synergistic effects on diabetic wound healing and oxidative parameters in diabetic rats.Materials and methods: In this study, diabetic rats were divided into control, untreated, Carbopol 974P treated, topical treatment, and oral gavage treatment. Ellagic acid and Carnosic acid combination were applied topically and oral gavage to the full-thickness excisional wounds of all animals except the control group. We investigated oxidative events by malondialdehyde, glutathione, nitric oxide, protein carbonyl, collagen spectrophotometrically, …


Cannabinoid Receptor Ligands Modulate Fibrosis And Inflammation In Idiopathicpulmonary Fibrosis: A Preliminary Study, Sevi̇l Köse, Seli̇n Önen, Merve Gi̇zer, Esi̇n Boduroğlu, Uğur Gönüllü, Petek Korkusuz Dec 2024

Cannabinoid Receptor Ligands Modulate Fibrosis And Inflammation In Idiopathicpulmonary Fibrosis: A Preliminary Study, Sevi̇l Köse, Seli̇n Önen, Merve Gi̇zer, Esi̇n Boduroğlu, Uğur Gönüllü, Petek Korkusuz

Turkish Journal of Biology

Background/aim: There is no specific pharmacological treatment regimen for idiopathic pulmonary fibrosis (IPF). Therefore, new anti-inflammatory therapeutic strategies are needed. Cannabinoids (CBs) that are known for their inflammation-modulating and anti-fibrotic effects may be potential medication candidates for the treatment of IPF. Our aim is to evaluate the inflammation-modulating and anti-fibrotic effects of CB receptor (CBR) agonists and antagonists in lipopolysaccharide (LPS) stimulated human lung healthy fibroblast, epithelial cells, IPF fibroblast cells and monocytes.Materials and methods: We detected CBRs in the human lung healthy (LL24) and IPF fibroblast cells (LL29), epithelial cells (A549) and monocytes (THP-1) by flow cytometry (FC). We …


Development Of An Immunodiagnostic Assay For The Detection Of Sugarcane Mosaic Virus, Hafiz Muhammad Khalid, Najam Us Sahar Sadaf Zaidi, Naeem Rashid, Muhammad Tahir Dec 2024

Development Of An Immunodiagnostic Assay For The Detection Of Sugarcane Mosaic Virus, Hafiz Muhammad Khalid, Najam Us Sahar Sadaf Zaidi, Naeem Rashid, Muhammad Tahir

Turkish Journal of Biology

Background/Aim: Sugarcane mosaic virus (SCMV; genus Potyvirus and family Potyviridae), poses a significant threat to global sugarcane cultivars, including those in Pakistan. The aim of this study was to develop a rapid and effective diagnostic tool for detection of SCMV, enabling timely implementation of control measures to mitigate potential yield losses.Materials and Methods: The study focused on the in silico analysis; physicochemical properties, immunogenicity and subcellular localization of the SCMV coat protein (CP). The SCMV coat protein (CP) gene was synthesized, cloned and expressed in Escherichia coli. The recombinant fusion coat protein (rFCP-SCMV) was purified and used to generate polyclonal …


Combinational Therapy Of All-Trans Retinoic Acid (Atra) And Sphingomyelin Induces Apoptosis And Cell Cycle Arrest In B16f10 Melanoma Cancer Cell, Zeynep İşlek Köklü, Eli̇f Li̇dya Şanverdi̇, Başak Karadağ, Mehmet Hi̇kmet Üçişik, Ezgi̇ Taşkan, Fi̇kretti̇n Şahi̇n Dec 2024

Combinational Therapy Of All-Trans Retinoic Acid (Atra) And Sphingomyelin Induces Apoptosis And Cell Cycle Arrest In B16f10 Melanoma Cancer Cell, Zeynep İşlek Köklü, Eli̇f Li̇dya Şanverdi̇, Başak Karadağ, Mehmet Hi̇kmet Üçişik, Ezgi̇ Taşkan, Fi̇kretti̇n Şahi̇n

Turkish Journal of Biology

Background: Melanoma arises from the uncontrolled multiplication of melanocytes, posing an escalating global health concern. Despite early detection and surgical removal being crucial, metastatic melanoma poses treatment challenges, with limited options like chemotherapy and immunotherapy. All-trans retinoic acid (ATRA), a natural metabolite of vitamin A, has shown promise in melanoma treatment by inducing differentiation, apoptosis, growth arrest, and immune modulation. However, ATRA treatment alone can lead to resistance and relapse. Sphingomyelin (SM) also plays a role in inhibiting melanoma progression by apoptotic cell death.Objective: This study investigated combinational anticancer effects of ATRA and SM on in vitro B16F10 melanoma cells.Method: …


Predictors Of Sedimentary Organic Carbon In Seagrass Vegetated And Unvegetated Sediment In The Tamar Estuary, United Kingdom, Kathryn Pogson Dec 2024

Predictors Of Sedimentary Organic Carbon In Seagrass Vegetated And Unvegetated Sediment In The Tamar Estuary, United Kingdom, Kathryn Pogson

The Plymouth Student Scientist

Seagrass meadows are considered significant natural carbon sinks due to their ability to store large amounts of organic carbon (Corg) in their sediments. ‘Blue carbon strategies’ aim to utilise and enhance this ability to mitigate climate change. However, assessing the Corg content and the habitat characteristics that influence this, in both seagrass vegetated and adjacent unvegetated sediments is needed to improve ‘Blue Carbon’ assessments. Currently, adjacent unvegetated sediments are excluded from Blue Carbon assessments as investigations rarely incorporate them into study design, despite evidence suggesting that they can also store significant amounts of Corg. Mean …


The Impact Of Artificial Light At Night On The Distribution Of Sea Turtles In The Mediterranean, Molly R. Blyth Dec 2024

The Impact Of Artificial Light At Night On The Distribution Of Sea Turtles In The Mediterranean, Molly R. Blyth

The Plymouth Student Scientist

Artificial light at night (ALAN) poses a significant threat to a wide array of species across the world. In coastal areas, artificial lighting is known to disrupt sea-finding behaviour of sea turtle hatchlings and to deter females from nesting beaches. Yet, sea turtles spend the majority of their lifetimes in the sea, where the influence of ALAN on sea turtle distribution has not previously been studied. Using a recently published atlas of ALAN under the sea, this study analysed an online dataset of sea turtle sightings throughout the Mediterranean Sea, to look for a relationship using a binomial generalised linear …


Microplastics In The Mix: Types And Retention Of Microplastics Within A Mixed Species Seagrass Meadow In The Tamar Estuary, Ida S. Kreuze Dec 2024

Microplastics In The Mix: Types And Retention Of Microplastics Within A Mixed Species Seagrass Meadow In The Tamar Estuary, Ida S. Kreuze

The Plymouth Student Scientist

Microplastic pollution in coastal systems is becoming increasingly prevalent and a commonly discussed topic in science and the media. Seagrass beds have been identified as highly vulnerable environments to microplastic pollution due to their nature as traps for particulate matter in the water column, and their role in habitat production and blue carbon storage makes them of high conservation concern. This study examined a mixed species seagrass bed in the Tamar Estuary in Plymouth Sound, composed of Nanozostera noltei and a morphology of Zostera marina, to identify how seagrass shoot density and sediment particle size impacted the number and …


Rooting For Resilience: Investigating The Success Of Seagrass Restoration Methods, Olivia K. Stockdale Dec 2024

Rooting For Resilience: Investigating The Success Of Seagrass Restoration Methods, Olivia K. Stockdale

The Plymouth Student Scientist

Seagrasses generate vital ecosystem services to coastal communities, whilst also protecting marine biodiversity. Despite their significance, seagrass ecosystems face a plethora of threats from both anthropogenic and natural sources, causing a 20 % loss of seagrass area over the last century. To combat this, numerous restoration methods exist for seagrass habitats globally, with varying degrees of success. Through a comprehensive systematic review and subsequent meta-analysis, this study illustrates the varying success rates of different transplant and seed-based restoration methods over differing timescales. Accounting for varying timescales, results showed that restoration method had a significant effect on success rate (χ2 …


Influence Of Patch Characteristics On Pollinator Behavior And Seed Production In Centaurea Stoebe, Abigail Hiltke Dec 2024

Influence Of Patch Characteristics On Pollinator Behavior And Seed Production In Centaurea Stoebe, Abigail Hiltke

Theses - ALL

Discontinuous, or patchy, landscapes may affect pollinator foraging behaviors and could potentially lower the fitness of isolated plant communities by limiting and/or altering pollination services. I tested this idea by examining changes in pollinator behavior in patches of spotted knapweed of different size, flower density, and distance from one another. Based on predictions from optimal foraging theory, I identified and measured key pollination promoting behaviors that may change when foragers are exposed to discontinuous landscape. These behaviors were pollinator visitation rates to patches, the number of visits to individual flowers within patches, and the handling time per flower. These factors …


Mechanism Of Impaired Cd8+ T Cell Activation During Ross River Virus Infection, Christopher Bullock Dec 2024

Mechanism Of Impaired Cd8+ T Cell Activation During Ross River Virus Infection, Christopher Bullock

Arts & Sciences Graduate Student Theses and Dissertations

Ross River virus (RRV) is a mosquito transmitted virus endemic to Australia that infects humans and causes acute symptoms of rash, fever, myalgia, and fatigue. Although systemic viral infection subsides within a few weeks, joint pain lingers in many patients for months. Active viral replication is not readily detected in this chronic phase, although persistent viral RNA has been found in the synovial fluid of patients. This can be studied in mice, which can be productively infected with RRV when inoculated in the foot. Like in humans, in the chronic phase of disease, viral RNA is still present in the …


Studying The Dynamics Of Neuromodulators In The Brain By Fluorescence Lifetime Imaging, Pingchuan Ma Dec 2024

Studying The Dynamics Of Neuromodulators In The Brain By Fluorescence Lifetime Imaging, Pingchuan Ma

Arts & Sciences Graduate Student Theses and Dissertations

Neuromodulators in the brain are fundamental to neuronal functions and animal behaviors in health and diseases. The modulatory actions of neuromodulators highly rely on their spatiotemporal dynamics. Recent research has demonstrated the importance of both sustained and transient change in neuromodulators, likely due to tonic and phasic neuromodulator release. However, no traditional methods could simultaneously record both types of dynamics. Fluorescence lifetime of optical reporters could offer a solution because it both allows high temporal resolution and is impervious to sensor expression differences across chronic periods. Nevertheless, no fluorescence lifetime change across the entire classes of neuromodulator sensors was previously …


Exploring The Homeostatic Functions And Driving Forces Of Lymphatic Outflow Pathways From The Central Nervous System, Zachary Matthew Papadopoulos Dec 2024

Exploring The Homeostatic Functions And Driving Forces Of Lymphatic Outflow Pathways From The Central Nervous System, Zachary Matthew Papadopoulos

Arts & Sciences Graduate Student Theses and Dissertations

Lymphatic drainage from the central nervous system (CNS) has been noted and described for several hundred years, yet its physiological roles have remained unclear. The fluid homeostasis of the CNS has long stood as an area of scientific interest due to primary disorders including hydrocephalus. However, the early days of neuroimmunology leaned on the lack of lymphatic vasculature in the CNS as a contributing explanation for ‘immune privilege’ in the CNS. As a result, the importance of lymphatics in CNS homeostasis has remained poorly understood and controversial. Following a renaissance in interest in the contribution of lymphatics to CNS homeostasis, …


Cytoplasmic And Mitochondrial Calcium Influences Retinal Ganglion Cell Survival To Axon Injury, Sean Mccracken Dec 2024

Cytoplasmic And Mitochondrial Calcium Influences Retinal Ganglion Cell Survival To Axon Injury, Sean Mccracken

Arts & Sciences Graduate Student Theses and Dissertations

Retinal Ganglion Cell (RGC) death is the final outcome in optic neuropathies like glaucoma and traumatic optic nerve injury, which represent the leading cause of irreversible blindness worldwide. There are currently no treatments for these diseases targeting RGCs directly, and mechanisms underlying RGC death are unclear. Calcium ion (Ca2+) dysregulation occurs in almost all neurodegenerative conditions, including glaucoma, which has been studied in rodents using a robust injury model of traumatic axon injury, optic nerve crush (ONC). However, the impact of homeostatic Ca2+ regulation in RGCs response to glaucoma or ONC is unknown. Furthermore, while some mechanisms that regulate Ca2+ …


Achieving Inter- And Transdisciplinarity In Ecohealth: Insights From A Rodent-Borne Disease Project In A Polycrisis Era, Isabelle Arpin, Clémence Massart, Vincent Bourret, Guillaume Castel, Valeria Carolina Colombo, Jana Eccard, Jasmin Firozpoor, Maciej Grzybek, Heikki A. Henttonen, Herwig Leirs, Andrew Mcmanus, Ben Roche, Tarja Sironen, Vincent Sluydts, Peter Stuart, Annetta Zintl, Nathalie Charbonnel Dec 2024

Achieving Inter- And Transdisciplinarity In Ecohealth: Insights From A Rodent-Borne Disease Project In A Polycrisis Era, Isabelle Arpin, Clémence Massart, Vincent Bourret, Guillaume Castel, Valeria Carolina Colombo, Jana Eccard, Jasmin Firozpoor, Maciej Grzybek, Heikki A. Henttonen, Herwig Leirs, Andrew Mcmanus, Ben Roche, Tarja Sironen, Vincent Sluydts, Peter Stuart, Annetta Zintl, Nathalie Charbonnel

Publications

Introduction: Inter- and transdisciplinary research (ITDR) is increasingly promoted to address “wicked problems”, particularly in health sectors adopting approaches like Ecohealth. Our Ecohealth-inspired project on rodent-borne diseases, initiated just before the COVID-19 pandemic, provided an opportunity to evaluate ITDR implementation.

Methods: We employed a recently developed semi-quantitative evaluation method to measure our project’s success in achieving ITDR and analyzed factors influencing this achievement.

Results: The project showed strengths in system description, team task allocation, and data sharing, but had lower scores in engaging societal actors throughout the project cycle.

Discussion: We identified the underexplored influence of problem wickedness as a …


Technology Development Of High-Resolution Single-Cell Lineage Tracing For Cell Reprogramming Systems, Sadie Vanhorn Dec 2024

Technology Development Of High-Resolution Single-Cell Lineage Tracing For Cell Reprogramming Systems, Sadie Vanhorn

Arts & Sciences Graduate Student Theses and Dissertations

A critical element of cell identity is the cell that created the observed cell. This parent cell dictates many aspects of its identity, whether measured by function, phenotype, or specific assays. The cell’s lineage impacts the ability of the cell to differentiate into final cell types in development or successfully reprogram in direct cell reprogramming. Here, we evolve molecular barcoding techniques to increase the resolution of lineage recording at single-cell resolution. Using single-cell RNA-sequencing as the readout for this measurement, polyadenylated reporter gene transcripts with engineered 3’ untranslated regions were designed to initially label and then record lineage information. While …


Multi-Omic Analysis Of Phototrophic Extracellular Electron Uptake In Novel Rhodovulum Spp. Isolated From A Marine Estuary, Emily J. Davenport Dec 2024

Multi-Omic Analysis Of Phototrophic Extracellular Electron Uptake In Novel Rhodovulum Spp. Isolated From A Marine Estuary, Emily J. Davenport

Arts & Sciences Graduate Student Theses and Dissertations

Microbial metabolisms are incredibly versatile and dynamic, allowing adaptive strategies for growth in even the most limiting environments. For an ever-increasing number of microbes, this includes utilizing soluble or insoluble inorganic mineral species as electron donors, driving geochemical cycles and microbial metabolisms. This metabolic function of transporting electrons derived from the extracellular environment across cell membranes is called extracellular electron uptake (EEU). Within (photo)autotrophs, (p)EEU also sustains CO2 fixation to cell biomass, implicating a potentially fundamental role of microbial carbon cycling in aquatic and soil ecosystems. A model metabolic scheme of pEEU occurring in natural environments is photoferrotrophy, which pairs …


Gene Expression Regulation By Au-Rich Elements And Au-Rich Element Binding Proteins, Courtney Fay Jungers Dec 2024

Gene Expression Regulation By Au-Rich Elements And Au-Rich Element Binding Proteins, Courtney Fay Jungers

Arts & Sciences Graduate Student Theses and Dissertations

The regulation of messenger RNA (mRNA) splicing, stability, and translation efficiency are major modes for controlling gene expression – which is essential for life. RNA-binding proteins (RBPs) and microRNAs (miRNAs) are trans-acting factors that bind to cis-elements influencing the stability and translation of the mRNA transcript. AU-rich elements (AREs) are cis-elements that are targeted by AU-rich element binding proteins (ARE-BPs). Here, I show a novel role for AREs and AU-rich element binding protein 1 (AUF1) during alternative splicing and report on interactions of RBPs and miRNAs to design a new treatment for breast cancer by interrupting these interactions in the …


A Filter-Based Model Of Visual Recognition, Olivia Rose Bockler Dec 2024

A Filter-Based Model Of Visual Recognition, Olivia Rose Bockler

Arts & Sciences Graduate Student Theses and Dissertations

Visual recognition, a key perceptual process, enables primates to identify faces, food, tools, and potential threats in their environment. Cortical neurons along the ventral visual stream—spanning from early visual cortex (V1) through inferotemporal cortex (IT), with long-range projections to ventrolateral prefrontal cortex (vlPFC)—are essential for visual recognition. Traditional models propose that neuronal representations increase in complexity in each stage of this pathway, culminating in object-specific representations in higher-order cortex. However, this hypothesis remains debated, particularly as artificial visual models have countered that individual neurons along this pathway may function more as filters contributing to distributed representations of objects. Thus, this …


Aging, Fast And Slow: Gene Expression Signatures Of Physiological Age Vs. Future Lifespan In Caenorhabditis Elegans, Matthew Mosley Dec 2024

Aging, Fast And Slow: Gene Expression Signatures Of Physiological Age Vs. Future Lifespan In Caenorhabditis Elegans, Matthew Mosley

Arts & Sciences Graduate Student Theses and Dissertations

An outstanding question in the field of aging biology is the origin of variability in lifespans among members of the same species. Traditional wisdom dictates that differences in one individual’s genes or environment, “nature” and “nurture,” could predispose that individual to a long or short life. However, these explanations are radically incomplete. Even in a model system as homogenous as C. elegans, using an isogenic population in a lab-controlled environment, we observe a distribution in lifespans comparable to that seen in outbred human populations. The first part of this dissertation focuses on characterizing this non-genetic, non-environmental variability in the aging …


Water Quality Assessment Of Three Ponds In The Plaster Creek Watershed, Orin Daspit, Salome Giessmann, Kennedi Pepin, Andrew Slagter, Sydney Wagenmaker Dec 2024

Water Quality Assessment Of Three Ponds In The Plaster Creek Watershed, Orin Daspit, Salome Giessmann, Kennedi Pepin, Andrew Slagter, Sydney Wagenmaker

Student Papers and Reports

Ponds are commonly found in urban areas serving as both an aesthetic and ecological feature. The water quality of these ponds can make important contributions to the overall health of the watershed in which they reside. This study analyzes three ponds within the Plaster Creek Watershed: the Southbridge Condominium Association Pond, the Calvin University Seminary Pond, and the Calvin University Ecosystem Preserve Kettle Swamp. This project aims to provide the Southbridge Condo Association with data that will inform future remediation actions. Using water samples collected over three days, E. coli, pH, nutrients, and total dissolved solids were measured in each …


Understanding Sequence Determinants Of Functional Protein Dynamics Using Biophysical Simulations And Experiments, Upasana Lakshmi Mallimadugula Dec 2024

Understanding Sequence Determinants Of Functional Protein Dynamics Using Biophysical Simulations And Experiments, Upasana Lakshmi Mallimadugula

Arts & Sciences Graduate Student Theses and Dissertations

Mutations in the sequence of proteins associated with a disease often increase its risk or severity. They can also be a barrier to developing effective therapeutics for such diseases. One way in which mutations affect function is by altering dynamics that elude structural studies. Observing these changes requires methods that can report on movements of the protein on various timescales and is an ongoing challenge in biophysics and biochemistry. In this study I will use both experimental and computational techniques that can report on such dynamics to explore how small sequence changes shift the conformational landscape and consequently the function …


Avian Adaptation To Thermal Gradients, Justin Wheeler Baldwin Dec 2024

Avian Adaptation To Thermal Gradients, Justin Wheeler Baldwin

Arts & Sciences Graduate Student Theses and Dissertations

Life on Earth has adapted to extremely different temperatures worldwide. However, across distant branches of the tree of life, animals in similar temperature environments often share similar phenotypic traits. Specifically, traits that bear on the ratio between an individual’s surface area (e.g. appendage length) and its volume (e.g. body size) are particularly important for temperature regulation and are codified in canonical biogeographical rules. Although these global patterns of finding larger-bodied (Bergmann’s Rule) and shorter-limbed (Allen’s Rule) animals in colder regions are widely upheld, they also show substantial variation. It remains poorly understood why some animals conform to these biogeographical rules …


Sustainable Plastics From Plastic Metabolisms: Leveraging Purple Non-Sulfur Bacteria For Polyhydroxyalkanoate Synthesis, Eric Michael Conners Dec 2024

Sustainable Plastics From Plastic Metabolisms: Leveraging Purple Non-Sulfur Bacteria For Polyhydroxyalkanoate Synthesis, Eric Michael Conners

Arts & Sciences Graduate Student Theses and Dissertations

Purple non-sulfur bacteria (PNSB) are a taxonomically diverse group of gram-negative bacteria representing some of Earth’s most metabolically versatile life, with many genera capable of switching between the four major metabolic modes – chemoheterotrophy, chemoautotrophy, photoheterotrophy, and photoautotrophy. Today, we exploit this diversity to explore fundamental questions about microbial metabolism. At the same time, many researchers are eager to use PNSB as tools for biotechnological innovations. Yet there exists a gap between fundamental biology and applied science. Part of the challenge is that we rely on a handful of model organisms – namely, members of the genera Rhodopseudomonas and Rhodobacter …