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The No3-/-O2 Respiration Ratio Of The Deep Sedimentary Biosphere In The Pacific Gyres, Yiya Huang

Open Access Master's Theses

Organic matter produced in the ocean has an average C/N ratio of 106:16 (the Redfield ratio). However, during transport to the seafloor, N is preferentially respired. This results in depletion of the N relative to C in the organic matter that fuels subseafloor microbial communities. It has also been argued that preferential depletion of organic N occurs in sediment. This depletion may force sedimentary microorganisms to reduce nitrate or fix dinitrogen, which requires the expenditure of a significant amount of additional energy in oxic sediment. Thus the availability of organic nitrogen may place a fundamental control on energy budget and …

Exploring Social Resilience In Marine Protected Areas – A Case Of Indonesia‘S Coral Triangle, Abdul Halik

Open Access Master's Theses

The term ―resilience‖ has a very long and rich history. The term itself received a widespread attention since Holling‘s seminal paper in 1973 on system ecology. Since then, the term resilience has been widely used and defined in many academic disciplines. The examination of social resilience in the context of overall coastal community resilience has been developed during the last few years. Such studies have been important in determining factors influencing the acceptance of MPAs in resource dependent communities.

The concept of social resilience has been defined mostly at the community level, and less so at the individual level. In …

A Responsive Particle Coating For Emulsion Formation At The Oil-Water Interface, Sarah Beaton Fields

Open Access Master's Theses

Emulsions were prepared using lipid-coated silica nanoparticles as a stabilizer, and the effects of type of lipid coating, lipid tail structure, type of oil, and concentration of lipid-coated silica nanoparticle on the stability, morphology and size of these emulsions were investigated. Three different methods for coating silica nanoparticles were used, resulting in three different particle types: partial bilayer/monolayer-coated silica particles (PBC SNPs), bilayer-coated silica particles (BC SNPs), and monolayer-coated silica particles (MC SNPs), which were evaluated for their efficacy in dispersing different types of oil. Dipalmitoylphosphatidylcholine (DPPC) and dioleoylphosphatidylcholine (DOPC) were used as lipid coatings to examine the effect of …

Multi-Species Interactions In Fish Populations On The Northwest Atlantic Coastal Shelf, Minho Kang

Open Access Master's Theses

Multispecies interactions (predation and competition) are known to have important consequences for the dynamics of marine fish populations. These interactions depend on the spatial overlap among fish species in the community. Several approaches have been used to quantify species interactions, including production models and age- (or length) structured multispecies models. In this study, multi-species biomass dynamics models were extended to account for food-web interactions in multiple spatial areas (Gulf of Maine, Southern New England, and Georges Bank). A total of 15 fish species collected from the study areas were aggregated into four trophic groups: non-migrating benthivores (haddock, yellowtail flounder, winter …

Estimates Of Micro-, Nano-, And Picoplankton Contributions To Particle Export In The Northeast Pacific, Brendan L. Mackinson

Open Access Master's Theses

The contributions of micro-, nano-, and picoplankton to particle export were estimated from measurements of size-fractionated particulate ²³⁴Th, organic carbon, and phytoplankton indicator pigments obtained during five cruises between 2010 and 2012 along Line P in the subarctic northeast Pacific Ocean. Sinking fluxes of particulate organic carbon (POC) and indicator pigments were calculated from ²³⁴Th– ²³⁸U disequilibria and, during two cruises, measured by sediment trap at Ocean Station Papa. POC fluxes at 100 m ranged from 0.65 – 7.95 mmol m^-2 d^-1, similar in magnitude to previous results at Line P. Microplankton pigments dominate …

Immunohistochemical Localization Of The Neuropeptide Rfamide In The Hypostomal Nerve Net Of Hydra Vulgaris, Bailey Munro

Open Access Master's Theses

This study examined the distribution and localization of the neuropeptide arginine-phenylalanine-amide (RFamide) in the hypostomal and tentacular nerve net of the cnidarian polyp Hydra vulgaris. Immunohistochemical techniques were used to visualize three RFamide-positive distinct nerve ring structures, nerves and neurites throughout the ectoderm of the hypostome and tentacles of ablated hypostomes. Two RFamide-positive circumhypostomal nerve rings are reported here: an inner ring located near the mouth and an outer ring located beneath the tentacle attachment sites. Both rings are consistent with rings labeled with anti-α-tubulin; the outer ring is also coincident with a GABA_B receptor-antibody-labeled ring previously described …

Ecological Benefits Of The Marine Stewardship Council Ecolabel: A Global Analysis, Sarah Blackstock

Open Access Master's Theses

Recent reports suggest that many of the world's commercial fisheries are overfished, and therefore require rebuilding. Ecolabels have been introduced as a potential method to mitigate this chronic misuse of natural resources. These labels are intended to indicate to consumers that a product is sustainable. Assuming consumers value the ecolabel, their business provides a market benefit to fishermen in exchange for the sustainable exploitation of fish stocks. Though some fisheries ecolabels have been in operation for over a decade, little research has been done to examine their measurable benefits, economic or ecological. Here, we analyze the ecological effects of the …

Early Spring Phytoplankton Dynamics In The Subpolar North Atlantic: The Influence Of Heterotrophic-Protist Herbivory, Francoise Morison

Open Access Master's Theses

To assess the importance of herbivory by heterotrophic protists in relation to mixed-layer depth prior to the spring phytoplankton bloom, we measured phytoplankton growth and heterotrophic-protist grazing rates during the March/April 2012 EuroBasin Deep Convection cruise in the subpolar North Atlantic. We performed 15 dilution experiments during 2-4 visits at one shelf (160 m) and two deep (~1300 m) stations. Of the two deep stations, one had a mean mixed-layer depth of 476 m, whereas the other was stratified (46 m). Euphotic depth averaged ~70 m at both stations. Initial chlorophyll-a varied from 0.2 to 1.9 μg L^{-1 …}

Centrifugation-Based Assay For Examining Nanoparticle-Lipid Membrane Binding And Disruption, Aihong Xi

Open Access Master's Theses

Physical disruption of cellular membranes arising from interactions with engineered nanoparticles is an important, but poorly understood aspect of nanotoxicology and nanomedicine. Model cellular membranes (i.e. lipid bilayers) can be used to identify interaction mechanisms, and most studies have largely focused on lipid bilayers supported on solid planar or spherical substrates. While useful and informative, these systems do not accurately represent an intact cell membrane because they restrict the elastic motion of the bilayer and the capacity for mechanical changes. Free standing bilayers are preferred, but add complexity. Given the importance of nanoparticle–membrane interactions in nanotoxicology and nanomedicine, and the …

Tumor-Penetrating Acetalated Dextran Nanoparticles Capable Of Tandem Delivery Of Agents For The Treatment Of Lung Cancer, Qihua Sun

Open Access Master's Theses

The overall survival rate for patients diagnosed with lung cancer is still extremely low and many affected patients are not eligible for first-line treatments such as surgery, chemotherapy, and radiation for the treatment due to the severe side effects associated with these therapies. Paclitaxel (PTX) along with imatinib mesylate are currently first-line therapies for many types of cancer (Kelly 2001, Schiller 2002). However, the successful delivery of paclitaxel faces many challenges due to its lipophilic nature and high protein affinity, which often results in low bioavailability. Solubilization of drugs such as PTX, enhanced tumor accumulation, and toxicity attenuation of such …

Design And Evaluation Of 5′-O-Dicarboxylic And Polyarginine Fatty Acyl Derivatives Of Anti-Hiv Nucleosides, Bhanu Priya Pemmaraju Venkata

Open Access Master's Theses

2′,3′-Dideoxynucleoside (ddNs) analogs are the most widely used anti-HIV drugs in the market. Even though these drugs display very potent activities, they have a number of limitations when are used as therapeutic agents. The primary problem associated with ddNs is significant toxicity, such as neuropathy and bone marrow suppression. Due to their hydrophilic nature, they have poor cellular uptake. Some of these nucleoside analogs develop resistance over a period of time. Furthermore, these analogs themselves are not pharmacologically active, and undergo three-step phosphorylation in order to become active. Of these steps, the first step is usually a slow and rate-limiting …

The Biology And Population Ecology Of Deep-Sea Red Crabs, Chaceon Spp. In The North Atlantic Ocean, Imam Syuhada

Open Access Dissertations

Red crab (Chaceon spp.) fishery resources exist on both sides on the North Atlantic, and the fisheries that harvest these resources seek to maintain their sustainability. To be able to conduct fishery assessments with less uncertainty, resource managers need a better understanding of the life history characteristics of the species, more recent information on the abundance and distribution of the resource, and finally reliable estimates of the levels of exploitation and the effects of harvesting of the resources. This study contributes to the body of knowledge of the resource in the western Atlantic resource and red crab fishery …

Microbial Community Composition Of Marine Biofilms In A Northern Temperate, Lauren Killea

Open Access Master's Theses

Marine biofilms are microbial aggregates that ubiquitously develop on substrates in seawater. Biofilms are not simple layers of microorganisms adhering to a surface followed by new organisms growing on top, but they instead have a complex developmental process making biofilms dynamic, diverse and functional communities. The negative effects of biofilms on ships, underwater cables and pipelines have spawned research in antifouling approaches; however, little is known about their development in a northern temperate estuary, such as Narragansett Bay. The goal of this study was to investigate the first steps in biofouling in this area by assessing biofilm biomass through chlorophyll, …

Identification Of Secondary Metabolite Gene Clusters Of Bacteria From South Pacific Gyre Subseafloor Sediment, Liwei Zhu

Open Access Master's Theses

Secondary metabolites are organic compounds that are not directly involved in the key processes (growth, reproduction and development) of an organism. They are commonly targeted in pharmaceutical science for drug discovery. Secondary metabolites that have been used in drug discovery have been derived from plants, invertebrates and microbes. Microbes, bacteria in particular, have contributed greatly and will continue to play an important role in new drug discovery. Among the bacteria from all environments, marine bacteria are a vast reservoir for many potential useful bioactive compounds. Recent studies using marine bacteria for pharmaceutical use mainly focused on the bacteria collected from …

Depression, Social Support, And Self-Rated Health In Older Adults, Kristen Frady

Open Access Master's Theses

Little research has explored factors indirectly related to health that may influence self-rated health (SRH) in older adults. Even less research has explored the relationship between perceived social support and SRH. The purpose of this study was to explore a health-related factor, depression, and an indirectly related to health factor, social support, as predictors of self-rated health in older adults. It explored three primary research questions: 1) Are there significant differences in older adults’ SRH scores when examined by demographic factors such as age, education, and marital status? 2) Are depression and social support correlated with SRH and is one …

Corrosion Protection Of Al5086 And Sensitized Al5086 Using A Titanate Based Conversion Coating, Andrew Murphy

Open Access Master's Theses

Chromate conversion coatings have been widely used in the materials industry, particularly on aluminum, to provide corrosion protection. Due to their toxicity and harmful environmental effects, replacement coatings have been sought. An alternative process to chromate conversion coatings using the titanate ion was developed and tested on 5086-H32 aluminum alloy and sensitized 5086-H32 aluminum alloy.

Electrochemical impedance spectroscopy (EIS) was employed to quantify the performance of the coating, while scanning electron microscopy (SEM) along with energy X-ray dispersive spectroscopy (EDS) were used to examine the surface and surface composition of the samples. Auger electron spectroscopy (AES) was used to determine …

The Relationship Between Co-Sleeping And Self-Regulation In Early Childhood, Bie-Shuein Chu

Open Access Master's Theses

Co-sleeping has been considered as a dangerous sleeping practice for infants by some parents and pediatricians. However, past research found that co-sleeping in early childhood has a positive influence on both physical and mental development as well as the parent-child relationship, which suggests that co-sleeping may have a positive influence on self-regulation development. This study aims to investigate the relationship between co-sleeping and two self-regulation constructs: socioemotional control and cognitive control by analyzing data from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B). After excluding the unqualified cases and weighing the sample size with adjusted DEFF weight, the final analytic sample …

Co-Evaluation Of Success Components In Salt Marsh Restoration And The Shellfish Industry On Outer Cape Cod, Ma, Katherine A. Castagno

Open Access Master's Theses

Salt marshes in their natural form provide innumerable ecologic, economic, and aesthetic benefits to coastal communities. Salt marsh restoration projects have been implemented along coastal landscapes in an attempt to reclaim their original ecosystem services. The ecological and social components of restoration, like its connection to the shellfish industry, are well understood, but the inherent linkages between the components are not. Through the co-evaluation of these components, social and ecologic linkages are identified and assessed.

This project explores the shellfish industry of five outer Cape Cod towns containing salt marshes that have undergone restoration: Orleans, Eastham, Wellfleet, Truro, and Provincetown. …

Effect Of Silica Nanoparticle Aggre-Gate State On Pickering Emulsion For-Mation And Stability, Maximillian Sender

Open Access Master's Theses

During the Deepwater Horizon Oil Spill in 2010 approximately 210 million gallons of crude oil was released into the Gulf of Mexico. To enable bacterial degradation the oil had to be dispersed into small oil droplets, which was achieved using 1.84 million gallons of chemical surfactants. As these surfactants have questionable environmental impacts, the idea of this research project is to use silica nanoparticles as a model particle to form Pickering emulsions and to study oil-mineral aggregate (OMA) formation. Pickering emulsions typically consist of oil droplets stabilized by solid particles instead of surfactants. Silica might be suitable for this as …

Development Of An Underwater Flapping Foil Tow-Test System, Samuel L. Rauworth

Open Access Master's Theses

Autonomous Underwater Vehicles (AUVs) using conventional methods of propulsion cannot operate in a dynamic environment such as the surf zone or around a reef. Bio-inspired propulsion mechanisms can provide the capabilities required to deal with the hazards of these locations. Animals such as birds, fish, and turtles use flapping foils as a means of propulsion and high maneuverability. Robotic flapping foils can be applied similarly to underwater vehicles like the AUV, Finnegan the RoboTurtle from MIT. Finnegan used four flapping foil "turtle fins" each with two degrees of freedom. One of those fins was outfitted to house force sensors which …

Paleoenvironmental And Paleolandscape Reconstructions Of Greenwich Bay Region, Ri, Cameron E. Morissette

Open Access Master's Theses

A paleoenvironmental and paleolandscape reconstruction of two separate sites in the Greenwich Bay region of RI was completed for use in the Paleocultural Landscapes Project. Investigations of a lacustrine sediment record in Warwick, RI were completed in order to develop a regional paleoenvironmental reference record. Investigations of the acoustic sub-bottom record in Greenwich Bay, RI were completed in order to develop paleolandscape reconstructions of the observed depositional environments for future use in an archaeological site prediction model.

For Chapter one, we took a single sediment core from Gorton Pond, Warwick, RI in the summer of 2013 for the purpose of …

Microplate Methodologies Applied To Environmental Biotechnology, Farrah Solomon

Open Access Master's Theses

Microarray technology is a high-throughput technique that allows a researcher to reduce the amount of reagents for each experiment as well as conduct multiple experiments with varying conditions simultaneously with the capability of analyzing this data quickly. Such microarray techniques have been applied in different fields such as environmental, pharmaceutical, microbiology, and biomedical among others (Kricka 2001).

Chapter 1 provides an introduction to microarray technology with a description of three different techniques: Phenotypic Microarray, DNA Microarray and Protein Microarray, used to study different aspects of microorganisms.

Chapter 2 presents the first manuscript, “A novel application of microarray technology to respiration …

I. Functionalization Of Crytpohane Cages For Xenon Mri Ii. Vanadium Catalyzed Oxidative Coupling Of Sp3 C – H Bonds To Heteroarenes, Marissa Simone

Open Access Master's Theses

The lack of resolution and selectivity in current imagining techniques such as x-ray, optical, and magnetic resonance imaging (MRI) has excelled the development of new biosensor technologies. Cryptophane A, a molecular cage composed of two cyclotriveratrylene (CTV) units connected by alkoxy bonds, can be turned into biosensors by attaching a target moiety capable of binding to a particular analyte. Cryptophanes can encapsulate xenon making it an attractive biosensor candidate for detection by hyperpolarized xenon-129 (HP-¹²⁹Xe) MRI. Further detection enhancement is achieved by using a technique called hyperpolarized chemical exchange saturation transfer (HYPER-CEST). One of the key challenges in …

Investigation Of Nitrogen Cycling Using Stable Nitrogen And Oxygen Isotopes In Narragansett Bay, Ri, Courtney Elizabeth Schmidt

Open Access Dissertations

Estuaries regulate nitrogen (N) fluxes transported from land to the open ocean through uptake and denitrification. In Narragansett Bay, anthropogenic N loading has increased over the last century with evidence for eutrophication in some regions of Narragansett Bay. Increased concerns over eutrophication prompted upgrades at wastewater treatment facilities (WWTFs) to decrease the amount of nitrogen discharged. The upgrade to tertiary treatment – where bioavailable nitrogen is reduced and removed through denitrification – has occurred at multiple facilities throughout Narragansett Bay’s watershed. Nitrogen remains limiting to primary production in the Bay proper which led to speculation that primary production throughout the …

A Genomic And Electrophysiological Study Of Photoreception In The Eyeless Cnidarian Hydra Vulgaris, Stephanie L. Guertin

Open Access Dissertations

Hydra are tubular coelenterates with two germ layers, the endoderm and ectoderm. A ring of five to eight tentacles surround an oral pore, and the animal attaches to the substrate via adhesion of the peduncle at the opposite end. They possess a complete ectodermal nerve net, with nerve fibers running within the ectoderm throughout the body and along the length of the tentacles (Hufnagel 1976.) Hydra has two nerve rings. One nerve ring surrounds the mouth and is thought to coordinate mouth opening. A second ring, located at the base of the tentacles, coordinates movements of the body, tentacles, mouth, …

Risk, Promotive, And Protective Influences On Adolescent Alcohol Use Milestones, Scott D. Martin

Open Access Dissertations

Research focused on the initiation and development of alcohol use among adolescents can inform professionals, families, and preventative strategies. Much of the research on adolescent substance use among this population focuses on risk. This study investigated a model of the initiation of adolescent alcohol use milestones including first full drink, first time engaging in heavy drinking, and first time being drunk, extending the risk perspective by emphasizing a model of resilience. This was done by simultaneously including risk, promotive, and protective influences in a single model. It was hypothesized that parental monitoring and reasons for abstaining and limiting drinking would …

Black Carbon Concentrations, Sources, And Fluxes In The Tropical Atlantic Ocean, Kari Ann Pohl

Open Access Dissertations

Black carbon (BC) is the highly graphitized byproduct of incomplete combustion that could be a sink for fixed carbon. Little data is currently available for BC concentrations and fluxes to remote marine environments and there are often great discrepancies between model simulations and actual field measurements. This research analyzed BC concentrations in the mixed boundary layer, surface water, and deep pelagic sediments of the Tropical Atlantic Ocean in order to understand the fate and transport of BC to the marine environment. It also aimed to assess the importance of aeolian versus fluvial BC deposition. Black carbon concentrations were elevated in …

Microbial Diversity And Connectivity Within And Between Oceanic And Marine Sedimentary Communities, Emily Ann Walsh

Open Access Dissertations

Our knowledge of microbial life residing in the oceans- photic and aphoticand within the subseafloor sediment has grown exponentially within the last few decades. This is partly because of advances in next-generation sequencing technology, which has provided an opportunity to address previously unanswerable questions regarding microbial diversity and biogeography (Hamady & Knight, 2009; Petrosino, Highlander, Luna, Gibbs, & Versalovic, 2009). By utilizing a next-generation sequencing approach, I determined microbial community compositions and assessed their response to environmental and geographic variation within and between five different oceanic regimes (i) the South Pacific Gyre (SPG), (ii) the Eastern and Central Equatorial Pacific …

Phytochemical And Biological Investigation Of Gallotannins From Red Maple (Acer Rubrum) Species, Hang Ma

Open Access Dissertations

This study investigated the phytochemical constituents, primarily gallotannins, present in a proprietary extract, namely MaplifaTM, from leaves of the red maple (Acer rubrum L.) species as well as their biological activities and mechanisms of action. Although the red maple species has been traditionally used as folk medicine by Native American Indians for numerous health benefits, the bioactive chemical constituents of the leaves of the red maple still remain unknown. This study carried out the identification of phytochemicals targeting gallotannins, a class of polyphenols, from red maple leaves by using various chromatographic separation techniques and spectroscopic approaches. Furthermore, compounds from the …

Mercury Bioaccumulation In Cartilaginous Fishes From Southern New England Coastal Waters: Contamination From A Trophic Ecology And Human Health Perspective, David L. Taylor, Nicholas J. Kutil, Anna J. Malek, Jeremy S. Collie

Graduate School of Oceanography Faculty Publications

This study examined total mercury (Hg) concentrations in cartilaginous fishes from Southern New England coastal waters, including smooth dogfish (Mustelus canis), spiny dogfish (Squalus acanthias), little skate (Leucoraja erinacea), and winter skate (Leucoraja ocellata). Total Hg in dogfish and skates were positively related to their respective body size and age, indicating Hg bioaccumulation in muscle tissue. There were also significant inter-species differences in Hg levels (mean ± 1 SD, mg Hg/kg dry weight, ppm): smooth dogfish (3.3 ± 2.1 ppm; n = 54) > spiny dogfish (1.1 ± 0.7 ppm; n = 124) …