Digital Commons Network^™

An Exploration Of The Quantitative Methods Used In The Study Of Phytoplankton Population Dynamics, Vitul Agarwal

Open Access Dissertations

Phytoplankton account for about half of all global net primary production. They are responsible for fueling marine fisheries, modulating the climate cycle, and forming the base of the marine food web. Some phytoplankton taxa play critical roles in coastal and lake ecosystems by forming harmful algal blooms (HABs), which can severely impact local communities’ economic revenue and human health. Given their importance, recent decades have seen a broad interest in understanding and predicting the variability of phytoplankton populations; however, there are limited resources that identify the relative strengths and weaknesses of analysis approaches used to study phytoplankton population dynamics. Research …

Developing Effective Physical And Chemical Adjuvants For Influenza And Tumor Vaccines, Yibo Li

Open Access Dissertations

An adjuvant is a pharmacological substance added to a vaccine to enhance the intensity, breadth and endurance of the immune responses. Traditional discovery and development of vaccine adjuvants mainly based on empirical experiences have been slow, but the situation has improved in the past two decades as more molecular mechanisms of vaccine adjuvants were revealed. Now it has been widely recognized that most adjuvants activate innate immune system by targeting pattern recognition receptors (PRRs) such as toll-like receptors (TLRs) to enhance adaptive immune responses. PRRs are proteins expressed mainly on innate immune cells, such as dendritic cells (DCs) and macrophages, …

Design, Simulation, And Rapid Prototyping Of Soft Robotic Actuators For Deep-Sea Applications, Alexander Yin

Open Access Dissertations

A new design and rapid prototyping approach for hydraulic soft actuators was developed and used to create bio-inspired underwater soft actuators that were tested and applied in the field. Underwater soft-bodied animals demonstrate complex approaches to move around the ocean and sophisticated methods of physically interacting with other organism and objects. Studying the functional design and kinematics of these animals can provide insight and solutions for complex tasks and locomotion, and soft robotics provides pathways to create complex actuators that imitate or are inspired by these animals. However, creating a complex soft actuator is currently an arduous and time-consuming process …

Mechanistic And Toxicokinetic Analysis Of Perfluoroalkyl Substances: Proteomics Approach And The Role Of Fatty Acid Binding (Fabp), Seyed Mohamad Sadegh Modaresi

Open Access Dissertations

Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals used in many industries, known for their resilience and resistance to degradation. The extended half-lives of PFAS in the human body result in bioaccumulation, with serum half-lives for perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexane sulfonic acid (PFHxS) estimated at 3.4, 4.6, and 7.1 years, respectively. PFAS primarily accumulate in the liver, hypothesized due to their resemblance to fatty acids and their binding with liver fatty acid-binding proteins (LFABP), affecting lipid metabolism and leading to liver toxicity. Although extensive research has been performed on long-chain PFAS over the past decade, …

Treading Carefully In The Deep Ocean: Insights Into The Effects Of Artificial Light And Sound From Robotic Platforms On Pelagic Animal Surveys Using Active Acoustics And Low-Light Imaging Techniques, Rendhy Moreno Sapiie

Open Access Dissertations

Science and technology are coupled disciplines. Breakthroughs in ocean science are often pertinent to the ability to observe physical, chemical, and biological processes at the right temporal and spatial scales, which typically involves the use of robots. Large, powerful, and extremely capable, the scientific work-class remotely operated vehicle (ROV) is the golden standard when observing fine temporal scale intricate processes in the full ocean stratum and has unraveled important discoveries in deep-sea biology and ecology. Sound, light, and hydrodynamic forces produced from these vehicles are sources of disturbances that may impact quantitative observations in the twilight zone, an environment absent …

An Investigation Of Alkb-Family Dna Repair Enzymes And Their Interaction With Synthetic, Modified Oligonucleotides, Samuel Dean Howarth

Open Access Dissertations

Chapter One will detail the synthesis, purification, and characterization of DNA oligonucleotides containing one of fifteen modified nucleic acid bases. For each modification, relevant background information is provided to highlight its biological significance. This chapter primarily focuses on the development of oligonucleotide stocks for use in future biochemical and cellular assays. Several of these modifications are recognized substrates of AlkB-family enzymes, while others remain uncharacterized as potential substrates.^1-4 The discovery of novel substrates for AlkB-family enzymes can be facilitated through comprehensive in vitro biochemical assays, contingent upon the availability of well-characterized substrate stocks. The methods and findings presented here …

Enhancing Green Sea Urchin (Strongylocentrotus Drobachiensis) Production Toward Sustainability, Tara Plee

Open Access Dissertations

The green sea urchin (Strongylocentrotus droebachiensis) fishery was once prosperous in the Gulf of Maine, peaking in the 1980s and early 1990s. However, since the early 1990s, the fishery has dramatically declined despite having harvesting restrictions. To sustain the industry, production through aquaculture is necessary, but hatchery production methods are not yet optimized, with settlement success and post-settlement survival as low as 1-5%, and the spatial scale for field grow-out may be limited in some regions due to climate change. Additionally, there are knowledge gaps in fishery management regarding whether oversized S. droebachiensis help sustain natural stocks. This …

The Distribution And Habitat Use Of Semi-Aquatic Mammals In A Changing New England Landscape, Josh Crockett

Open Access Dissertations

Semi-aquatic mammals (i.e., animals that depend on both terrestrial and aquatic environments for their daily needs) are an ecologically and economically important group, but they are often difficult to monitor because of their restricted habitat which makes them unlikely to appear in monitoring schemes designed for all mammals (e.g., camera trapping). Rhode Island is home to several semi-aquatic mammal species, including North American beavers (Castor canadensis), North American river otters (Lontra candensis), and muskrats (Ondatra zibethicus). Historically, these species were all exploited for their furs, which led to drastic declines in otter and (especially) …

Learning From The Past: Environmental Impacts On Coral Performance, Reproduction, And Epigenetic Inheritance, Danielle M. Becker

Open Access Dissertations

Coral reef ecosystems face extreme challenges due to increasing ocean temperatures caused by anthropogenically induced global climate change and require reproductive replenishment for reef persistence. Corals and other marine invertebrates have exhibited the capacity for environmental memory, or the retention of information from prior environmental experiences, which can be inherited by subsequent generations (e.g., via non-genetic mechanisms). However, less is known about how molecular modifications in the coral epigenome influence acclimatization and adaptive responses to environmental variation within and across generations. Here, I present three manuscripts testing different mechanisms involved in coral’s physiological, reproductive, and epigenetic response to environmental perturbation …

Improving The Diet Quality Of Wic-Participating Women Using Digital Food Environments, Yarisbel Melo Herrera

Open Access Dissertations

Maternal diet plays a critical role during the perinatal period, impacting both short- and long-term health outcomes in women and their children. Lower-income individuals are at higher risk of having a low diet quality. Therefore, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) aims to reduce the negative impacts of low socioeconomic status on the diet of its participants (low-income pregnant and postpartum women and children up to age 5) to promote optimal short- and long-term health outcomes. Numerous studies show that WIC improves children’s diet quality, but associations in women have been insufficiently evaluated. While there …

Differential Gene Expression Analysis: Genomic Response In Human Peripheral Blood Following Neutron Exposure For Radiation Biodosimetry Applications, Rashmi Basavaraj

Open Access Dissertations

Radiation Biodosimetry is a crucial method for evaluating the biological consequences of radiation exposure on health outcomes. This technique estimates radiation dose by analyzing the biological effects it causes in the body becomes especially valuable in situations where traditional physical dosimeters, like badges, are unavailable or unreliable. In these scenarios, Radiation Biodosimetry enables accurate dose assessment, which is critical for making informed decisions during emergency response (triage), treatment planning, and long-term health risk evaluation.

Current biodosimetry methods struggle to accurately estimate radiation doses, especially for low-dose exposures or complex scenarios involving both neutrons and photons, like those arising from improvised …

Telechelic Polymers As High-Performance Rheological Modifiers In Biomimetic Polymer-Linked Emulsions, Daniel P. Keane

Open Access Dissertations

Due to the complexity of biological tissue and the numerous challenges associated with research into biological particle transport, it is of interest to scientists to develop a synthetic mimic that can replicate key attributes of multicellular tissue. The work presented in this dissertation details the design, characterization, and application of a synthetic material for use as a phantom material in research into biological particle transport. Furthermore, the designed materials introduce exciting polymer physics problems and present broad potential uses as rheological modifiers for colloidal systems and 3D printing inks. The polymer-linked emulsions which form the basis of this work are …

Racial And Ethnic Disparities In Hospital Practices That Support Breastfeeding In The United States, Jane Lazar Tucker

Open Access Dissertations

Breastfeeding is the optimal form of infant nutrition and has many health benefits for mothers as well as infants (CDC, 2022a; Victora et al., 2016). Though rates of breastfeeding have improved in recent years, disparities in breastfeeding persist among Black and Hispanic women compared to White women (Beauregard et al., 2019; Chiang et al., 2021), despite similar intentions to breastfeed across all racial/ethnic groups (Hamner et al., 2021). Hospital practices that support breastfeeding, such as the baby being placed skin-to-skin immediately after delivery or staying in the room with the mother throughout the hospital stay, are known to predict breastfeeding …

Mechanistic Approach To Understanding Adverse Liver Outcomes Related To Pfas Exposure In Neonatal And Adult Mice, Emily Kaye

Open Access Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a unique class of over 15,000 manmade chemicals that are still widely used in manufacturing and are resistant to degradation. Accumulation in the environment and general population has been associated with an array of adverse health outcomes. Perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and perfluorohexanesulfonic acid (PFHxS) specifically have been associated with markers of liver injury, high serum cholesterol, thyroid disease, low fetal birth weight, suppressed vaccine response, and cancer. Exposure to PFAS is commonly investigated individually, however, humans are exposed to a multitude of PFAS daily. Additionally, with the pervasive nature of these …

Drivers Of Phytoplankton Diversity And Primary Production Across Time And Space: Insights From The Northeast U.S. Shelf, Diana N. Fontaine

Open Access Dissertations

In the ocean, a group of drifting, photosynthetic cells called phytoplankton are vital to Earth’s carbon cycle. Through primary production, a process whereby phytoplankton remove carbon dioxide from the atmosphere and convert it to organic carbon, these cells play a pivotal role in supporting marine food webs. Primary production is generated by numerous different types and sizes of phytoplankton; this myriad of phylogenetic diversity and large size range influences the fate of organic carbon in the global ocean. Due to their importance, phytoplankton community dynamics, including primary production and taxonomic diversity, are routinely studied. Much of this work, however, tends …

Dna Damage, Modification And Repair, Xianhao Zhou

Open Access Dissertations

DNA is necessarily to be stable and intact since it is the repository of genetic information in each living cell. However, DNA is not inert, and it is vulnerable to the endogenous and environmental assaults including reactive oxygen species (ROS), ultraviolet (UV) light, and various carcinogens. Exposure to these DNA damaging agents is associated with various adducts ranging from small methyl or etheno adducts to bulky adducts such as acetylaminofluorene. These resulting damages, if not repaired, will lead to replication block or mutation which can eventually cause cancer or other genetic diseases.

The research covered by this dissertation falls into …

Identification Of Cellulose Synthase Structural Features Involved In Cellulose Synthesis Complex Formation, Jamie Lamkin

Open Access Dissertations

Cellulose is a microfibrillar polysaccharide component of plant cell walls and consists of bundles of β-1,4-linked glucan chains. In addition to being important for plant cell walls, cellulose is also used by humans for a variety of purposes such as biofuels and building materials. Cellulose is produced by the integral plasma membrane enzyme Cellulose Synthase (CESA) and multiple CESA proteins can combine to form a six-lobed rosette structure called a Cellulose Synthesis Complex (CSC). In seed plants CSCs appear to be hetero-oligomeric, comprising three different CESA isoforms. However some non-seed plants, such as the bryophyte Physcomitrium patens, can form …

Cryptic Lineages Matter For Coral Conservation Under Climate Change, Matías Gómez Corrales

Open Access Dissertations

Coral reefs are among the most biodiverse ecosystems on the planet, yet we do not fully grasp the extent of their diversity or the mechanisms driving the evolution of these rich ecosystems. In recent decades, coral cover has decreased worldwide due to rising seawater temperatures caused by human activities. This thermal stress leads to coral bleaching (i.e., the loss of endo-photosymbiotic microalgae), resulting in widespread coral mortality. Despite this, some corals can withstand increased temperatures that are lethal to most conspecifics. These unprecedented coral losses and different species-specific responses to global warming pose the challenge of losing biodiversity …

Enhancing Forest Monitoring And Management In Southern New England Through Gis Analysis, Remote Sensing, And Predictive Models: Assessing Tree Mortality And Enhancing Infrastructure Resilience, Liubov Dumarevskaya

Open Access Dissertations

Forests have immense economic value, contributing to industries such as timber production, nontimber forest products, and ecotourism (Wang et al., 2022). Additionally, forest ecosystems play a crucial role in mitigating climate change by acting as carbon sinks (Yingchun et al., 2012). However, forests also pose hazards to humans and infrastructure. Fallen trees, limbs, and contact of tree branches with power lines create numerous hazards to public safety, property damage, and substantial economic losses from power outages. Studies report that the total cost of storm-related power outages in the United States range from $20-150 billion annually (Campbell et al., 2021; Swaminathan …

Societal Impacts Of Harmful Macroalgal Blooms On Caribbean Communities, Kenneth Hamel

Open Access Dissertations

Pelagic Sargassum species, long considered a vital component of Caribbean ecosystems, began to arrive on and near shore in unprecedented quantities starting in 2011; these arrivals have transformed many Caribbean people’s perspectives of these macroalgae from a native benefit to an alien invader, and are now regarded widely as a harmful algal bloom (HAB). HABs often receive attention for the ecological and economic damage they present, but other human dimensions are less commonly considered, and this is doubly true of Sargassum events. This dissertation was intended to fill increasingly pronounced research gaps by providing exploratory evidence that can be useful …

Chasing Soot Across The Sea: The Fate And Transport Of Particulate Black Carbon In The Equatorial Atlantic, Samuel D. Katz

Open Access Dissertations

This study investigated BC in the equatorial Atlantic Ocean and Congo River outflow, aiming to elucidate its origins, distribution, fluxes and understand methodological differences in BC quantification. Sediment and atmospheric samples were collected from the Equatorial Atlantic and Congo River outflow. For the sedimentary analysis, the chemothermal oxidation at 375°C method was primally used, while different BC quantification methods were employed with the Congo core, together with stable and radiogenic carbon isotope measurements, to trace BC sources and age. BC air samples were quantified using the thermal optical transmission method, air mass back trajectories, and polycyclic aromatic hydrocarbon (PAH) diagnostic …

Microfluidic Paper-Based Devices For The Detection Of Chemical And Biological Agents, Hojat Heidaribafroui

Open Access Dissertations

This work was motivated by two needs: to develop low-cost, high-sensitivity, and accurate systems for detecting phosphate in seawater, and to create a platform technology by integrating Bi-Material Cantilever (B-MaC) valves for rapid and affordable biosensors that can be used at home or point-of-care settings to detect pathogens.

Detecting low levels of phosphate in the seawater using an inexpensive sensor is crucial for marine scientists to make informed decisions on where to measure next, compared to the current method of collecting samples and analyzing them ashore. To address these needs, we developed a portable infrared lightbox that can be wirelessly …

Design, Dynamic Modeling And Control Of Soft Robots, Xiaotian Chen

Open Access Dissertations

Inspired from biological systems, researchers are designing soft robots to replace conventional rigid body robots in many applications, including human-machine interaction, manipulation, medical instrumentation and wearable devices.

Soft robots, due to their flexible bodies capable of achieving complex movements, are suitable for motion in unstructured complex environments. Moreover, soft robots can provide a more pleasant interaction experience for humans, or grip and manipulate fragile objects. However, because of the potential ability of the soft robot, controlling the soft robot still remains as a difficult task, as the soft robot contains high complexity and non-linearity. Currently, machine learning is involved in …

Cranberry Vine And Its Effects On The Periparturient Ovine And Her Offspring, Delaney Smith

Open Access Dissertations

Gastrointestinal nematodes (GIN) are a major health concern globally, particularly for small ruminant producers. The most deadly of these GIN is an anemia-inducing parasite called Haemonchus contortus. Infections of H. contortus are most severe during what's known as the periparturient period (PPP), which is the last 6 weeks of gestation and first 8 weeks of lactation in maternal animals. Widespread genetic resistance of H. contortus to the traditionally used chemical dewormers have led producers and researchers alike to turn to the plant kingdom for answers. Plant based compounds have been used as bioactive compounds for centuries to cure a …

Elucidating The Mechanisms Of Stress Tolerance In Reef-Building Coral Holobionts, Emma Strand

Open Access Dissertations

Coral reefs worldwide are threatened by climate change effects like increasing ocean warming and ocean acidification. These increased pressures cause a dysbiosis between the coral host, algal endosymbionts, and associated coral microbiome that results in the coral host expelling algal endosymbionts, leaving the coral host with a stark white ‘bleached’ appearance. Without their endosymbionts, coral hosts are forced to sustain themselves energetically with heterotrophy instead of relying on the autotrophic carbon and energy sources that once came from the algal endosymbionts. When this response, termed ‘coral bleaching’, happens reef-wide during an extreme wave of increased ocean temperatures, this is called …

The Impact Of Climate Stresses In Water Quality Of Agricultural, Urban And Forested Watersheds In Rhode Island, Shiva Shrestha

Open Access Dissertations

Hydrological regime and nutrient dynamics are associated with hydrological setting of any watershed. Human interventions have direct and indirect impacts on these hydrologic setting and watershed response. The increasing anthropogenic pressure has continued to degrade the water quality. This may lead to eutrophication that can seriously harm the water quality and aquatic ecosystems (Vitousek 1997).

The effective mitigation strategies in land and water management practices should have good understand of water and nutrient fluxes in watershed and relating them to spatio-temporal hydrologic factors (Liang et al., 2020).

The best approaches of the management strategies should always start from monitoring and …

Development Of Polymeric Nano- And Microparticle-Based Controlled Release Platforms, Ryan Ivone

Open Access Dissertations

The success of the development of drug delivery formulations hinges upon their ability to maintain therapeutic efficacy, while simultaneously aiming to minimize off-site side effects and reduce the dosing burden often faced by patients. Localized formulations deliver therapeutics directly to the disease site and can help circumvent physiological obstacles such as the first pass effect, which remains one of the primary barriers for oral drug delivery. Barriers such as the first pass effect can drastically reduce the overall bioavailability of a formulation, potentially requiring a higher initial dose to remain therapeutically effective. However, many compounds demonstrate dose dependent side effects, …

Development And Characterization Of Nano- And Microparticles For Pulmonary Drug Delivery, Matthew Freeman

Open Access Dissertations

Pulmonary drug delivery is a rapidly growing area of interest in the field of inhalable therapeutics and provides the possibility for specialized engineered inhalable drug-loaded particles capable of improving treatment efficacy. Pulmonary drug delivery provide several advantageous when compared to other routes of administrations, as therapeutics delivered to the lungs avoid the first-pass effect of the liver, which is a major hurdle for other routes of administration. The potential for drug degradation is also decreased as the lungs have low to no enzymatic activity. Furthermore, the lungs have a large surface and are highly vascular, resulting in rapid onset of …

Pesticides, Polymers, And Pollution: Use Of Organic Chemistry To Combat Threats To Pollinator Health, Kassie Picard

Open Access Dissertations

Organic synthesis is a powerful tool that is used to solve real world problems from drug development to polymer synthesis. The basis of this work is the development and use of organic chemistry techniques to study pollinator health via the synthesis of small molecule pesticides and detection of microfibers

Pyrethroids are a class of synthetic pesticides with a wide range of agricultural, medical, and veterinary applications. These pesticides are particularly appealing due to the highly tunable molecular structure leading to selectivity towards pests and consistently low mammalian toxicity. The varroa mite, varroa destructor, is an ectoparasitic mite that infests honey …

How Does Practicing Mindfulness Relate To Consumer Willingness To Attend Events Post-Pandemic?, Gillian N. Palmer

Open Access Dissertations

A TWO ESSAY DISSERTATION EXAMINING MINDFULNESS IN THE EVENTS INDUSTRY

The restrictions and social concerns that limited social interaction during the first eighteen months of the COVID-19 pandemic had a negative impact on the multi-trillion-dollar event industry, which includes large hallmark events like festivals and concerts and business events like trade shows. In addition to the impact made to the events industry, there was a social and mental wellness impact on consumers as they learned how to live a "new norm" lifestyle. As vaccines and reductions in social distancing guidelines opened a path to return to physical, in-person events, event …