Digital Commons Network^™

Biogeography And Nested Patterns Of Genetic Diversity In The Diatom Thalassiosira Rotula, Kerry A. Whittaker

Open Access Dissertations

Diatoms are some of the most biogeochemically important organisms on our planet, responsible for up to 40% of primary production in the ocean. Diatoms are also the most diverse group of algae, exhibiting high levels of cryptic speciation, and remarkable clonal diversity nested within species and populations. As single cells within a dynamic fluid environment, diatoms possess the potential to disperse throughout the globe. Yet, despite the global dispersal potential of these ecologically important organisms, little is understood about the structure and distribution of diatom diversity throughout the globe, or its ecological significance. The goal of this work was to …

Assumed To Be Black: A Critical Examination Of Being Ascribed A Racial Status On A Predominately White Campus, Shontay Delalue King Francis

Open Access Dissertations

Colleges and universities continue to add diversity and internationalization as major components of their strategic planning efforts. Students from various racial, ethnic and national backgrounds are expected to live and work together in an intellectual environment while bringing with them various views of race and culture that are maintained through varying myths and misconceptions. This study looked at the technical and cultural definitions of what it means to be ‘Black’ in the U.S. and the stereotypes of being classified within that racial category.

The goal of this research study was to understand the experience of students from the African Atlantic …

Impact Of Phytoplankton Community Structure And Function On Marine Particulate Optical Properties, Malcolm Neil Mcfarland

Open Access Dissertations

Phytoplankton are an ecologically important and diverse group of organisms whose distribution, abundance, and population dynamics vary significantly over small spatial (cm) and temporal (minutes) scales in the coastal ocean. Our inability to observe phytoplankton community structure and function at these small scales has severely limited our understanding of the fundamental ecological and evolutionary mechanisms that drive phytoplankton growth, mortality, adaptation and speciation. The goal of this dissertation was to enhance our understanding of phytoplankton ecology by improving in situ observational techniques based on the optical properties of cells, colonies, populations, and communities. Field and laboratory studies were used to …

Application Of Polymer Systems To The Detection And Retention Of Explosives, Jonathan N. Canino

Open Access Dissertations

Obtaining, handling, and storing of explosives, especially primaries such as triacetonetriperoxide (TATP), presents significant obstacles to instrument manufacturers and K-9 trainers. Microencapsulation techniques were used to trap TATP in a plastic matrix rendering it safe to handle, store at room temperature, and release by heating. Detection of most explosive vapor is a challenge for current instrumentation. This work provides a study of polymer systems for the preconcentration of explosive vapor for use with portable explosive detection technologies, specifically molecularly imprinted polymers (MIPs).

Evaluating The Role Of Hypoglycemia & Comorbid Illness On Diabetes Management Behaviors, Saumitra Vijay Rege

Open Access Dissertations

Over the recent years, the incidence of diabetes has significantly increased. Use of preventive services and treatment with oral antidiabetic drugs (OAD) has remained cornerstone in the management of type 2 diabetes (T2DM). Despite strong evidence that treating diabetes using these disease management strategies decreases morbidity, mortality and complications, glycemic control as well as other diabetes related outcomes remain unsatisfactory. The prevalence of diabetes in the United States has grown vastly in proportion over the last few years with the American Diabetes Association estimating that 9.3% of the population suffered from diabetes in the year 2012. These estimates are expected …

Psychiatric Hospitalization To School Transitions: Examining Professional Perceptions Of Effectiveness And Fidelity, Jacqueline Michele Tisdale

Open Access Dissertations

The present study examined the effectiveness of adolescent psychiatric hospitalization-to-school transitions from the perspective of hospital and school-based mental health providers. Twenty-four school-based mental health professionals were surveyed to gain a better understanding of their experiences of reintegrating students to school following brief psychiatric hospitalization, including collaborations with hospital-based providers and contact with students’ parents during and after hospitalization. Fourteen hospital and school mental health providers completed written narrative responses based upon a case vignette to identify ideal transition processes, and also participated in a semi-structured interview to identify barriers to successful transition plan implementation. Data was gathered and examined …

Structural And Conformational Insights Into Bulky Arylamine-Induced Mutagenesis, Lifang Xu

Open Access Dissertations

Cancer is the second deadliest disease in the United States. Over 100 different types of cancers exist, among which lung, breast and prostate cancers are those most frequently diagnosed. Genetic factors are important. However, exposures to tobacco smoke and environmental pollutants are considered to be responsible for 75%–80% of cancer. About 6% of cancer deaths every year in the US are reportedly to be directly linked to known carcinogen exposures. Therefore, it is important to study the mechanisms of how the environmental carcinogens trigger cancer initiation. Most chemical carcinogens are metabolized into reactive species in vivo to interact with DNA, …

Studying Science: Students Gaining Access To The Community Of Practice Of Environmental Studies, Renee Johnson-Thornton

Open Access Dissertations

Although nearly equivalent percentages of black and white students entering college aspire to earn degrees in science, technology, engineering, and mathematics (STEM), a much smaller percentage of black students than white undergraduates complete STEM degrees (HERI, 2010). Thirty-six percent of black undergraduates who initially pursue STEM fields and go on to earn bachelor’s degrees switch to non- STEM majors, and 29.3 percent leave college before graduating, a rate 10 percentage points higher than that of their white counterparts (19.8 percent) (Chen, 2013). In the Environmental Sciences, of the 4,802 degree recipients in 2010, 81 percent (3,879) were white and only …

Model-Based 3-D Reconstruction Of Transparent Objects From A Single Image, Wiehrs Lewis Collier

Open Access Dissertations

This dissertation describes an interdisciplinary research project that spans computer-vision, imaging of biological nanoparticles via cryogenic transmission electron microscopy (cryo-tem), and bio-informatics / proteomics. This research introduces a new method for reconstructing individual biological particles imaged via cryo-tem with typical accuracies of 88% to 98%. This individual particle reconstruction (IPR) technique is based on a hidden Markov model derived from the underlying biological structure. The processing presented in this dissertation reconstructs each individual particle from a single image, which is in contrast to current approaches that can require tens of thousands of images to create an ensemble representation …

Characterization Of The Probiotic Mechanism Of Phaeobacter Gallaeciensis S4 Against Bacterial Pathogens, Wenjing Zhao

Open Access Dissertations

Infections by pathogenic marine bacteria are a major problem for both the shellfish and finfish aquaculture industries, causing severe disease and high mortality, which seriously affect aquaculture production and cause significant economic loss. Marine pathogens like Vibrio tubiashii and Roseovarius crassostreae frequently cause disease in a variety of shellfish. With the understanding that the use of antibiotics in large-scale aquaculture leads to the development and transfer of antibiotic resistance, investigation of probiotic approaches for the prevention of infectious disease has become important. In manuscript I, screening of bacterial isolates from Rhode Island marine organisms and environment using agar-based assay methods …

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 …

Prediction Of Structure Borne Noise Radiation And Propagation From Offshore Impact Pile Driving, Huikwan Kim

Open Access Dissertations

This study investigates prediction of structure borne noise radiation and propagation from offshore impact pile driving in shallow water environment. Noise generated by offshore impact pile driving radiates into and propagates through the air, water, and sediment medium. Predicting noise levels around the pile structure at sea is required to estimate the effects of the noise and vibration on marine life. This study used one of the commercial FE (Finite Element) code Abaqus 6.11 to calculate harmonic and transient response of the offshore wind turbine support structure and associated acoustic pressure amplitudes due to hydraulic hammer impact on top. First …

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 …

Opting-In Online: Participants’ Perceptions Of Knowledge Construction In Public Forum Communities, Jennifer C. Lee

Open Access Dissertations

This project examines knowledge making and sharing amid special interest forums, specifically, online forums for herp (reptile and amphibian) hobbyists. In doing so, it addresses a gap in rhetoricians’ understanding of publicness: its effect on writing and people’s perceptions thereof. Few studies measure public writing unless its telos is change or activism. Additionally, despite increased rhetorical scholarship focusing on new media, much current research on forums situates them in classroom-based learning and collaboration, neglecting online forums that are open to public access. This project is a naturalistic inquiry using qualitative methods to explore collaborative public writing that occurs in discourse …

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, …

Intrapartum Nurses’ Beliefs About Childbirth: A Descriptive Qualitative Study In Nurses That Provide Care To Women In Labor And Birth, Sylvia P. Ross

Open Access Dissertations

In the United States, a large gap exists between what is known as best evidence in maternal-newborn health and the routine practices at the frontline of maternity care. Intrapartum nurses are uniquely positioned to promote practices that are evidencebased and support the normal physiologic process of birth. This qualitative study explored intrapartum nurses’ beliefs about childbirth and the influence of their beliefs on their clinical practice, particularly practices that promoted normal physiologic birth. Semi-structured qualitative interviews were conducted with 10 intrapartum registered nurses using Rubin and Rubin’s (2012) responsive interview model. All participants practiced on a labor and delivery unit …

Portraits Of Novice Teacher Learning With Mentors In Urban Schools, Marjorie Kazin-Boyce

Open Access Dissertations

The purpose of this retrospective study was to examine the learning and development process of three new teachers who were paired with mentors in a formal induction program in an urban district. The qualitative case study focused on three teacher-mentor dyads who were interviewed about their experience during the teachers’ first year of teaching in middle and high school of the district. In addition to interviews with teachers and their mentors, the researcher examined documents that were part of the mentoring process such as teacher reflective journals or mentor feedback forms. Using the Purposeful, Ongoing Mentoring Model (Peno & Silva …

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 …

Nutritional And Immunological Evaluation Of Soy-Based Diets For Summer Flounder (Paralichthys Dentatus) Aquaculture, Daniel Ward

Open Access Dissertations

Summer flounder aquaculture has progressed significantly in the last twenty years, and diets have been optimized to provide optimal nutrition, ensuring a high quality final product. Recently, the focus of research has evolved toward finding a replacement for fish meal in diets for many species, as the demand for fish meal worldwide has caused the primary protein product to become increasingly economically volatile. Therefore, a series of experiments were designed to systematically evaluate feeds for summer flounder (Paralichthys dentatus) including soy-based products as the primary protein source. The first feed trial involved the comparison of three diets; a …

The Bovine Spermatozoal Transcriptome And Sire Fertility, Christopher James Card

Open Access Dissertations

The goal of this dissertation research was to characterize the spermatozoal transcript profile of bovine cryopreserved spermatozoa. The main goal was to sequence the complete transcript profile from a population of sires across a wide fertility range utilizing RNA-Sequencing (RNA-Seq). Sequencing was then conducted to compare the spermatozoal transcript profiles of higher and lower fertility sires in an effort to determine the presence or absence of spermatozoal transcripts that may aid in improving fertility testing in sires. In addition to RNA-Seq analysis, other semen parameters such as morphology, DNA fragmentation, and RNA amount were analyzed for relationships with fertility.

The …

Phytochemical Investigation Of The Traditional Botanical Medicine Iresine Celosia, Caroline Grace Killian

Open Access Dissertations

Iresine celosia L. is a traditional medicine used by the indigenous Mayan people for a variety of ailments. It is also the sole active ingredient in the Odyliresin™ formulation currently marketed to humans worldwide as an antioxidant and for the promotion of prostate health. However, Odyliresin™ has not been characterized phytochemically, or evaluated biologically for its intended use. This work represents the first comprehensive phytochemical investigation of the Odyliresin™ formulation botanical extract. To better understand its constitutive phytochemistry, a tailored isolation scheme was developed, using various chromatography resins (silica gel, LH-20), separation and purification techniques. In all, eleven compounds were …

Introduction And Establishment Of Three Parasitoids Of The Lily Leaf Beetle, Lilioceris Lilii, (Coleoptera: Chrysomelidae) In North America, Elizabeth A. Tewksbury

Open Access Dissertations

Following three years of discovery and evaluation, three larval parasitoids were imported from Europe and introduced into North America to control Lilioceris lilii (Coleoptera: Chrysomelidae), an introduced herbivore of native and cultivated lilies. The first species, Tetrastichus setifer Thomson (Hymenoptera: Eulophidae), introduced in Massachusetts in 1999, was found to be established in 2002. We made additional releases of T. setifer, introduced the parasitic wasps, Lemophagus errabundus Szepligeti (Hymenoptea: Ichneumonidae) and Diaparsis jucunda (Holmgren) (Hymenoptera: Ichneumonidae), and evaluated the establishment and distribution of the three parasitoids through 2013. Tetrastichus setifer is now established in Massachusetts, Rhode Island, New Hampshire, Maine, …

Historically Marginalized Groups In Psychological Science, Celeste Caviness

Open Access Dissertations

Over the past thirty years there has been a concerted effort to evaluate the inclusion of historically marginalized groups (HMG) – women, racial, ethnic, and sexual minorities, and low-income individuals – in research. This has been done through content analyses of research literature published in top-tier psychological journals. The purpose of this study was to examine the research literature to assess the degree to which the current literature includes ethnic, racial, and sexual minorities, women, and those of varying socioeconomic status and whether research questions focusing on historically marginalized groups are being examined within mainstream journals. Six issues from 2012 …

Three Essays On The Economics Of Ecosystem Services And Land Use Change, Tingting Liu

Open Access Dissertations

Over the past few decades, agricultural and forest lands in the northeast US have been lost to residential development. Combined with more intensive farming on remaining lands, these trends have led to losses in valuable ecosystem services from the agricultural and forest landscape. Narragansett Bay is also exhibiting an increasing array of eutrophic-associated symptoms, including low dissolved oxygen, fish kills, eelgrass loss, algae blooms, and loss of submerged aquatic vegetation (Narragansett Bay Estuary Program, 2008).

This dissertation contains three essays to quantify and value the changes in ecosystem services and to evaluate the effectiveness of policy for land use management. …

The Anti-Epilepsy Potential And Antagonism Of The N-Methyl-D-Aspartate Receptor By Diaminodiphenyls, Kyle Robert Scully

Open Access Dissertations

Epilepsy is a disorder characterized by the occurrence of seizures, which are periods of abnormally excessive synchronous neuronal activity in the brain. Affecting over 70 million people worldwide, many of whom do not respond to pharmacotherapy, there is a need for novel anticonvulsant compound discovery. Diaminodiphenyl compounds, a class of compounds shown to present anticonvulsive effects in vivo have been purported to exert their effects on the N-methyl-D-aspartate receptor (NMDAr); an excitatory, ionotropic receptor that is a key player in the functions of the glutamatergic system. The glutamatergic system is vital in the promotion of synaptic plasticity and has …

A Case Study Of Student And Teacher Relationships And The Effect On Student Learning, Patricia Brady Gablinske

Open Access Dissertations

This research study explored the affective domain of teacher-student relationships using a single case study design. This single case study produced a synthesis of information that guides a classroom teacher in the development and maintenance of her relationships with her students. The resulting analysis and interpretation provided a description of major themes that developed regarding strong teacher student relationships, as well as, specific components to the interactions considered essential for the student’s learning environment.

The outcome of this study is an account of experiences and procedures that guide the development and maintenance of relationships between a teacher and her students. …

Molecular Interaction In Carboxylesterases-Based Catalysis: Ontogenic Expression And Induction Through A Novel Element, Yi-Tzai Chen

Open Access Dissertations

Carboxylesterases (CES) catalyze both hydrolytic and synthetic reactions and play important roles in drug metabolism and lipid mobilization. Many factors such as age and dietary supplements have been shown to regulate the CES expression. The expression of CES1 shows the developmental regulation and is highly induced by antioxidants. The goals of this project were to determine whether CES2, like CES1, is developmentally regulated and to investigate how antioxidants induced the expression of CES1 at the molecular level.

The ontogenic studies showed the mRNA levels of CES2 exhibited a postnatal surge (1-31 days versus 35-70 days) in both liver and duodenum. …