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Molecular Self-Assembly Of Functionalized Pentacenes And Fullerenes On Metal Surfaces By Stm And Dft Investigations, Jun Wang

Doctoral Dissertations

Enormous efforts have been made in seeking alternative pathways to more effectively use solar energy. Organic solar cells, composed essentially of carbon-based organic molecular materials, have attracted considerable scientific and industrial attentions because of their economic and environmental benefits. It is advantageous to have the comprehension of the molecular structures and interfacial morphologies for these active molecular materials on substrates in the nanoscale regime.

Controlling the heterostructures of the molecular donor and acceptor materials is essential to overcoming the efficiency bottleneck in organic photovoltaics. Molecular self-assembly on patterned substrates provides a bottom-up approach to create well-controlled molecular heterojunctions and a …

Approaches To Modeling Pathogen And Natural Organic Matter Removals In Slow-Rate Biofilters, Jeffrey Dale Senders

Doctoral Dissertations

There are limited expressions capable of estimating removals in one of the world's oldest and most sustainable water treatment systems: slow-rate biofilters. This research addresses the problem by deriving semi-empirical models that predict pathogen and natural organic matter removals within these natural and engineered sand filters. The more complex pathogen model, or phenomenological colloidal filtration theory (pCFT), applies the 1937 Iwasaki solution to New England pilot scale E. coli observations. The derived pCFT was then calibrated through a series of experimental bench scale phases. Further pCFT validation came by way of a seamless application to multiple microorganisms. Viruses (MS2 as …

Interactions Of Shiga-Like Toxin-2 (Stx-2) From Escherichia Coli O157:H7 And The Bcl-2 Family Of Proteins During Host Cell Programmed Cell Death, Lia K. Jeffrey

Doctoral Dissertations

Stx-2 is a major contributor to the pathogenesis of Escherichia coli 0157:H7. Prior reports suggest that Stx-2 increases necrosis and apoptosis of a variety of host cells including those of endothelial origin as well as immune cells such as neutrophils (156). However, the role Stx-2 plays in delayed apoptosis of neutrophils is not fully understood given that previous studies have shown conflicting results (118, 51). The process of apoptosis is mediated by the Bcl-2 protein family (2, 46, 226). The purpose of this research was to define the molecular mechanisms of Stx-2 and Bcl-2 protein family interactions. These studies examined …

Identification And Stoichiometric Analysis Of The Monosomal Translational Complex, Xin Wang

Doctoral Dissertations

The identification of the components involved in translational complexes has relied primarily on in vitro studies. Determining which proteins associate together in these complexes, under what conditions they do so, and how the composition of the complexes change under different conditions have became the key issues of in vivo studies. After a one-step affinity purification, using a novel technique of analytical ultracentrifugation with a fluorescence detection system (AU-FDS) I have identified a 77S monosomal translational complex in the yeast Saccharomyces cerevisiae. Major components of the 77S complex include the 80S ribosome, mRNA, and components of the closed-loop structure, eIF4E, eIF4G1/eIF4G2 …

Engineering Lipases And Solvents For Trans/-Esterification Of Used Vegetable Oils, Michael Dore Gagnon

Doctoral Dissertations

Diminishing petroleum reserves and increasing environmental awareness has led to an urgent need to develop alternative fuels, such as biodiesel. However, the conventional method to produce biodiesel uses environmentally harmful chemical catalysts. A relatively new development in the production of biodiesel is through enzymatic trans/- esterification with a lipase catalyst. Despite several advantages, there are a few technical and economical obstacles that limit this process: (1) immiscibility of the hydrophilic methanol and hydrophobic triglyceride which results in the formation of an interface leading to mass transfer resistance, (2) insufficient availability of large quantities of inexpensive lipase suitable for catalysis, and …

Everyday Food Practices Among Three Low-Income Groups: Rural, Homeless, And Refugee, Amy L. Redman

Doctoral Dissertations

Lower-income groups are more susceptible to diet-related diseases like obesity, diabetes, and heart disease (CDC, 2010). They are also more likely to need food and nutritional assistance (USDA, 2011). Yet very little is known about the day-to-day food practices of these individuals and families. Many times those who are relatively adjacent in terms of income are assumed to have similarities in food consumption (Hupkens, Knibbe, & Drop, 2000); however, this has not been empirically examined. The main objectives of this research are to 1) gain an exploratory in-depth understanding of the everyday food practices of individuals in three low-income groups: …

Characterization Of The Prokaryotic Community Associated With The Giant Barrel Sponge, Xestospongia Muta Across The Caribbean, Cara L. Fiore

Doctoral Dissertations

Sponges have long been known to be ecologically important members of the benthic fauna on coral reefs. Recently, it has been shown that sponges, and their symbiotic microbes, are also important contributors to the nitrogen biogeochemistry of coral reefs. Here, I investigate the ecology and physiology of the microbial community associated the ecologically dominant sponge, Xestospongia muta. A natural experiment was conducted with X. muta form three different locations (Florida Keys, USA; Lee Stocking Island, Bahamas, and Little Cayman, Cayman Islands) to compare nitrogen cycling and prokaryotic community composition. The dissolved inorganic nitrogen (DIN) fluxes of sponges were studied using …

Characterization Of The Expression Profile Of Polyamine Biosynthetic Genes (Spermidine Synthase) And Polyamine Metabolic Regulation In Arabidopsis, Lin Shao

Doctoral Dissertations

Polyamines are ubiquitously distributed cationic compounds, which play important roles in numerous cellular functions in plants. This study was aimed at elaborating the regulation of polyamine biosynthetic gene expression and polyamine metabolism. The organ/tissue specific expression patterns of two genes encoding the polyamine biosynthetic enzyme spermidine synthase ( AtSPDS1 and AtSPDS2) were studied in Arabidopsis at different developmental stages using promoter::reporter approach. The two homologues showed similar ubiquitous expression with subtle differences being observed in certain tissues (e.g. root, siliques, and embryos). Neither transgenic manipulation by over-expression of AtSPDSI alone nor its concomitant expression with genes encoding other biosynthetic enzymes …

Movements, Dive Behavior And Trophic Ecology Of Leatherback Turtles (Dermochelys Coriacea) In The Northwest Atlantic, Kara Dodge

Doctoral Dissertations

The endangered leatherback turtle is a highly migratory predator that feeds exclusively on gelatinous zooplankton. Leatherbacks spend most of their lives submerged or offshore, and their at-sea biology (particularly that of males and sub-adults) is poorly understood throughout much of their range. I used satellite telemetry to monitor movements and dive behavior of nine adult and eleven sub-adult leatherbacks captured off Massachusetts, USA, and tracked throughout the NW Atlantic. Leatherback movements and environmental associations varied by oceanographic region, with slow, sinuous, area-restricted search behavior and shorter, shallower dives occurring in cool, productive, shallow shelf habitat at temperate latitudes. Leatherbacks were …

Patterns Of Cytosine Methylation In The Genome Of Caenorhabditis Elegans, Kazufusa Okamoto

Doctoral Dissertations

Recent large-scale comparative analysis of cytosine DNA methylation across diverse eukaryotes suggest that early features of DNA methylation present in the last common ancestor of all eukaryotes some 1.6 to 1.8 billion years ago included the methylation of gene bodies and transposable elements (Zemach, McDaniel et al. 2010; Parfrey, Lahr et al. 2011). These potentially ancient patterns may reflect a primitive role of methylation in transcriptional fidelity and as a mechanism to protect the germ line from transposon, or repeat, mediated mutation. Because spurious transcription and mutation are hypothesized to be among the critical limiting factors to genome size, an …

The Effects Of Biotic And Abiotic Factors On Byssogenesis, Growth And Movement Patterns Of The Blue Mussel, Mytilus Edulis, Yvette Louise Garner

Doctoral Dissertations

Blue mussels create extensive aggregations on intertidal and low subtidal shores in the Gulf of Maine, in which they modify habitat, trap sediments and create microclimates for many organisms. Mussels are an important aquaculture species worldwide, and play a major part of the economy of New England. Blue mussels produce collagenous byssal threads to anchor themselves to the substrate on wave swept shores. Byssogenesis, growth and movement abilities of mussels are influenced by a host of biotic and abiotic factors. In this dissertation I quantified byssogenesis and growth of the blue mussel, Mytilus edulis, affected by wave exposure, temperature, and …

Regulation Of The Catalytic And Allosteric Properties Of Photoreceptor Phosphodiesterase (Pde6) By The Glutamic Acid-Rich Protein-2 (Garp2), Wei Yao

Doctoral Dissertations

The photoreceptor phosphodiesterase (PDE6) must be precisely regulated to control the sensitivity, amplitude, and kinetics of the photoresponse during excitation, termination and adaptation to light stimulation in rod and cone photoreceptors. The central hypothesis of this thesis is that one PDE6 binding partner, the glutamic acid-rich protein (GARP2), may regulate PDE6 to reduce its "dark noise", enhance its sensitivity and conserve metabolic energy during rod photoresponse saturation.

The first aim of this research is to better understand the unique biochemical and biophysical characteristics of GARP2 in order to reveal its functional attributes for regulating PDE6 during phototransduction in rod photoreceptors. …

The Identification And Characterization Of The Interaction Between Upf1 And Pab1 During Nonsense-Mediated Decay & The Identification Of Novel Protein Complexes Associated With Translation Termination Factor Erf1, Roy Richardson

Doctoral Dissertations

There are still many protein interactions that occur during translation termination that are poorly understood. One of the important termination pathways still under investigation is nonsense-mediated decay (NMD), which rapidly degrades mRNAs that contain a premature stop codon (PTC). I identified that the interaction between Upfl, which is required for NMD, and PAB1 occurs via the RRM1 domain of PAB1 in the yeast Saccharomyces cerevisiae. Determining the role of this interaction during NMD was performed with pulse-chase assays using a PGKlpG mRNA. These assays revealed that the interaction between Upfl and PAB1 is required for a shift from distributive to …

Bacterial Biodegradation Of Soluble Crude Oil Hydrocarbons And The Influence Of Protists In Simulated Arctic Seawater And Sea Ice, Heather Ballestero

Doctoral Dissertations

With expected increases in vessel traffic, drilling, and exploration for petroleum and natural gas, the potential for an Arctic oil spill is heightened, yet knowledge of contaminant fate and behavior is limited in this environment. With challenging conditions in the Arctic and limited equipment caches, response will be extremely difficult. In freezing conditions, oil may become encapsulated in ice. Understanding biodegradation potential in this environment can dictate response options for spills that occur in Arctic marine waters. The influence of protists on bacterial biodegradation of water accommodated fractions (WAF) of petroleum hydrocarbons is unknown, yet important because it could enhance …

"I Am A Scientist": How Setting Conditions That Enhance Focused Concentration Positively Relate To Student Motivation And Achievement Outcomes In Inquiry-Based Science, Robin B. Ellwood

Doctoral Dissertations

This research investigated how student social interactions within two approaches to an inquiry-based science curriculum could be related to student motivation and achievement outcomes. This qualitative case study consisted of two cases, Off-Campus and On-Campus, and used ethnographic techniques of participant observation. Research participants included eight eighth grade girls, aged thirteen to fourteen years old. Data sources included formal and informal participant interviews, participant journal reflections, curriculum artifacts including quizzes, worksheets, and student-generated research posters, digital video and audio recordings, photographs, and researcher field notes. Data were transcribed verbatim and coded, then collapsed into emergent themes using NVIVO 9. The …

Utilization Of Copper Alloys For Marine Applications, Andrew Drach

Doctoral Dissertations

Utilization of copper alloy components in systems deployed in marine environment presents potential improvements by reducing maintenance costs, prolonging service life, and increasing reliability. However, integration of these materials faces technological challenges, which are discussed and addressed in this work, including characterization of material performance in seawater environment, hydrodynamics of copper alloy components, and design procedures for systems with copper alloys.

To characterize the hydrodynamic behavior of copper alloy nets, mesh geometry of the major types of copper nets currently used in the marine aquaculture are analyzed and formulae for the solidity and strand length are proposed. Experimental studies of …

Exploring The Importance Of Single Nucleotide Polymorphisms Of Hspa9 In Dna Of Sarcoma Patients, Christine M. Hebert

Honors Theses and Capstones

The aim of this project was to identify genetic variants that may influence the risk and progression of sarcoma through targeted genotyping of HSPA9 gene. It is important to look at genetic variants in DNA samples because if a variant is determined to be more likely than another, a screening for the particular variant can be done to identify a patient’s risk of sarcoma. The study population was sarcoma patients from the International Sarcoma Kindred Study. These patients had no mutations in p53 or MDM2. Genotyping data from the HapMap project (hapmap.org) for HSPA9 was used to identify the polymorphisms …

Assessing Translocation Of Nuisance And Rehabilitation Of Orphan Black Bears In New Hampshire, Wesley Earl Smith Jr.

Master's Theses and Capstones

This study evaluated translocation of nuisance and rehabilitation of orphan black bears as management strategies in New Hampshire. Bears were fitted with GPS collars to measure survival, movement, habitat selection, and conflict activity until denning. Survival of nuisance bears was high (73%) the first year, and they exhibited low return rates (28%) with only adults homing; homing declined as distance increased. Bears selected for both natural and human-dominated habitats, and most (55%) were documented in subsequent conflicts indicating that translocation does not eliminate nuisance behavior; some were harvested. Rehabilitated orphan bears had high survival (86%) in 2011 and were not …

Productivity And Physical Condition Of White-Tailed Deer In New Hampshire, Nicholas Lucian Fortin

Master's Theses and Capstones

This study assessed productivity and nutritional condition of deer in New Hampshire, and physical condition, productivity, and recruitment in northeastern North America. In New Hampshire, few fawns bred, but pregnancy rate and productivity of older deer were high and stable since the 1980s, despite substantially higher population density. Productivity increased due to a higher proportion of adults in 2011-2013; however, recruitment declined steadily suggesting that summer fawn mortality has increased. Nutritional condition declined throughout winter, and regardless of winter severity, most deer had depleted energy reserves and were in poor condition after April 1. These findings emphasize the need to …

Use Of Cover Crops For Weed Suppression And Nutrient Capture, Elisabeth Ann Hodgdon

Master's Theses and Capstones

Cover crops suppress weeds by competing for resources. The purpose of the first study was to quantify the effects of cover crops on weeds and the soil environment. Forage radish (Raphanus sativus L. var. longipinnatus 'Tillage Radish') was most effective at reducing weeds. The purpose of the second study was to quantify the effects of these cover crops planted the previous summer on growth of a test crop and residual weed populations. Test crop yield and chlorophyll levels were highest and weed populations were lowest in plots that had previously been planted with forage radish. In the third cover cropping …

Evaluating Phenotypic Differences Between High Tunnel Tomato Cultivars And The Functional Role Of Diversity In A Broccoli - Living Mulch Agroecostytem, Nicholas Warren

Master's Theses and Capstones

Recently, there has been a growing effort to increase the availability of locally grown food in New England, and the ecological and socioeconomic impacts of these changes require careful consideration. This work consists of two experiments evaluating typical food production systems in New England. The high tunnel tomato cultivar trial evaluates indeterminate beefsteak tomatoes for important phenotypic differences. Understanding these differences will aid in the selection of different cultivars of tomatoes for local growers. Increasing the intraspecific diversity of high tunnel tomatoes may help balance the tradeoffs observed between cultivars. The broccoli-living mulch experiment is an evaluation of the competitive …

Observations Of Pockmark Flow Structure In Belfast Bay, Maine, Christina L. Fandel

Master's Theses and Capstones

Vertical current and CTD profiles were acquired over a small, spherical pockmark and a larger, more elongated pockmark in Belfast Bay, Maine in July 2011. These observations showed evidence for mixing within the pockmarks, a rotational pattern that resembles open cavity flow, and incipient motion along the rims. Over the center of each pockmark, observations of uniform temperature properties below 12 m are indicative of mixing within the pockmark. The observed complex rotational structure over each pockmark shows significant rotation with depth and a greater degree of rotation during ebbing tide. These observations are qualitatively consistent with circulation patterns predicted …

Covalent Attachment Of A Diimine Tricarbonyl Re(I) Catalyst On Solid State Nano-Material Surfaces For Solar Carbon Dioxide Reduction, He He

Master's Theses and Capstones

Reduction of carbon dioxide to useful chemicals and fuels is of significant interest. Transition metal complexes, such as tricarbonyl rhenium(I) compounds, are efficient molecular catalysts for photocatalytic carbon dioxide reduction. To improve the stability and catalytic activity of homogeneous catalysts, a mesoporous silica material, SBA-15, was synthesized and applied as catalyst support for immobilizing the tricarbonyl rhenium(I) compound via both covalent bonding and physical adsorption. The covalently bonded tricarbonyl rhenium(I) catalyst in SBA-15 exhibited excellent stability and good activity during the photocatalytic reduction process, compared with its homogeneous counterpart and the physically absorbed one. Another solid-state nano-material, Kaolin, was also …

Trans Women And Aging: A Qualitative Study, Martha B. Leighton

Master's Theses and Capstones

Data from interviews with 11 transgender women ages 55 to 77 were used to examine the experiences of gender-diverse individuals throughout the lifespan. Specifically, qualitative methods were used to examine how participants had experienced discrimination, developed strengths and resiliencies as a response to discrimination, and employed strategies predicted by Hobfoll's Conservation of Resources Theory. Focused coding of the data revealed significant and pervasive discrimination in multiple settings and throughout the participants' lives. The data also, however, revealed a wide range of strengths and resiliencies and indicated that participants employed a variety of strategies that allowed them to amass, maintain, and …

Characterizing Winter Flounder (Pseudopleuronectes Americanus) Nursery Areas Using Otolith Microstructure And Microchemical Techniques, David Bailey

Master's Theses and Capstones

A preliminary study, using young-of-the-year winter flounder from 12 nursery areas from New Jersey to New Hampshire, evaluated indirect and direct measurements of nursery quality. Growth and condition indices (length d --1, weight d--1, Fulton's K and relative weight) were calculated from otolith microstructure to indirectly evaluate nursery quality. Boston Harbor, MA and Great Bay, NH were found to be the healthiest nurseries and the Niantic River, CT was found to be the least healthy nursery. In addition to these indirect indices, we conducted a study to determine the effectiveness of otolith microchemistry as a direct measurement of nursery habitat. …

Balancing Ecological And Economic Values In Northern Hardwood Stands: What Are The Trade-Offs?, Daniel Woock Kilham

Master's Theses and Capstones

New England has 32 million acres of forested land, 27.5 million acres are private and 13.5 million of those private forests are family owned. Two of the main landowner objectives of privately owned forests in New England are generating income and promoting biodiversity and nature. Objectives were to develop a rapid ecological assessment method to aid management of private forests and to determine any trade-offs between economic and ecological values. We measured economic and ecological values in our study site in New Hampshire, and simulated four harvest treatments to determine the effects of different silvicultural approaches. Ecological values were measured …

Response Of Tree Growth And Water Use Efficiency To Climate And Nitrogen Deposition In A Temperate Deciduous Forest In The Northeastern Us, Katie Jennings

Master's Theses and Capstones

Nitrogen (N) deposition and climate change are altering tree growth and may have important consequences for water use in northeastern forests. Intrinsic water use efficiency (iWUE), the trade-off between water loss and carbon fixed during photosynthesis, directly links forest carbon and water cycles. Dendrochronology and stable isotopes (delta13C and delta18O) were used to assess Quercus velutina growth and iWUE within a chronic N deposition experiment (20+ years of fertilization at low- and high-N rates). Fertilized trees exhibited sustained growth enhancement, with the greatest response observed for high-N trees. All fertilized trees improved their iWUE through increased photosynthetic rates, but was …

The Individual Tree And Forest Stand Level Impacts Of Winter Moth Defoliation In Eastern Massachusetts, Usa, Michael J. Simmons

Master's Theses and Capstones

Winter moth is a non-native invasive defoliator in New England. This thesis related host tree radial growth of individual trees in eastern Massachusetts to winter moth defoliation intensity using tree core analysis. Further, tree core analysis was used to identify winter moth defoliation events in several forest stands in eastern Massachusetts and these events were used to relate winter moth to stand level tree mortality and understory woody plant density. Quercus radial growth from 2005-2010 was negatively related to winter moth defoliation. In addition, Quercus mortality in mixed -- Quercus and Quercus - P. strobus forests in eastern Massachusetts was …

Production Of Bio-Jet Fuel From Microalgae, Marian Elmoraghy

Master's Theses and Capstones

The increase in petroleum-based aviation fuel consumption, the decrease in petroleum resources, the fluctuation of the crude oil price, the increase in greenhouse gas emission and the need for energy security are motivating the development of an alternate jet fuel. Bio-jet fuel has to be a drop in fuel, technically and economically feasible, environmentally friendly, greener than jet fuel, produced locally and low gallon per Btu. Bic jet fuel has been produced by blending petro-based jet fuel with microalgae biodiesel (Fatty Acid Methyl Ester, or simply FAME). Indoor microalgae growth, lipids extraction and transetrification to biodiesel are energy and fresh …

Toward Understanding The Economic And Ecological Outcomes Of Selection Silviculture On A Northern Hardwood Forest, Katherine Ann Sinacore

Master's Theses and Capstones

Single-tree selection (STS) and small-group selection (SGS) silviculture are widely used in the northeastern United States, but questions remain regarding the economic and ecological outcomes of these systems. To assess harvest treatment effects on northern hardwood forests, we examined an unmanaged stand (UNM) and STS and SGS managed stands within the Bartlett Experimental Forest of New Hampshire. For an economic perspective, grade and standing tree values were our metrics to evaluate changes in timber quality. After 60 years of management, the percentage of higher graded trees increased slightly for both the SGS and STS managed stands. However, current data suggests …