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Geoecology, Nishanta Rajakaruna, S. Boyd

Faculty Publications, Biological Sciences

No abstract provided.

Additional Lichen Records And Minerological Data From Metal-Contaminated Sites In Maine, I. D. Medeiros, A. M. Fryday, Nishanta Rajakaruna

Faculty Publications, Biological Sciences

No abstract provided.

A Small Subset Of Fruitless Subesophageal Neurons Modulate Early Courtship In Drosophila, David Tran, Geoffrey Meissner, Rachael French, Bruce Baker

Faculty Publications, Biological Sciences

We show that a small subset of two to six subesophageal neurons, expressing the male products of the male courtship master regulator gene products fruitlessMale (fruM), are required in the early stages of the Drosophila melanogaster male courtship behavioral program. Loss of fruM expression or inhibition of synaptic transmission in these fruM(+) neurons results in delayed courtship initiation and a failure to progress to copulation primarily under visually-deficient conditions. We identify a fruM-dependent sexually dimorphic arborization in the tritocerebrum made by two of these neurons. Furthermore, these SOG neurons extend descending projections to the thorax and abdominal ganglia. These anatomical …

Integrated Assessment Of Biological Invasions, Inés Ibáñez, Jeffrey M. Diez, Luke P. Miller, Julian D. Olden, Cascade J.B. Sorte, Dana M. Blumenthal, Bethany A. Bradley, Carla M. D'Antonio, Jeffrey S. Dukes, Regan I. Early, Edwin D. Grosholz, Joshua J. Lawler

Faculty Publications, Biological Sciences

As the main witnesses of the ecological and economic impacts of invasions on ecosystems around the world, ecologists seek to provide the relevant science that informs managers about the potential for invasion of specific organisms in their region(s) of interest. Yet, the assorted literature that could inform such forecasts is rarely integrated to do so, and further, the diverse nature of the data available complicates synthesis and quantitative prediction. Here we present a set of analytical tools for synthesizing different levels of distributional and/or demographic data to produce meaningful assessments of invasion potential that can guide management at multiple phases …

Diversity And Soil-Tissue Elemental Relations Of Vascular Plants Of Callahan Mine, Brooksville, Maine, U.S.A, Margaret Mansfield, Nathaniel Pope, Glen Mittlehauser, Nishanta Rajakaruna

Faculty Publications, Biological Sciences

Metal-contaminated soils provide numerous stressors to plant life, resulting in unique plant communities worldwide. The current study focuses on the vascular plants of Callahan Mine in Brooksville, ME, USA, a Superfund site contaminated with Cu, Zn, Pb, and other pollutants. One hundred and fifty-five taxa belonging to 50 families were identified, with the Asteraceae (21%), Poaceae (11%), and Rosaceae (9%) as the most species-rich families. Ninety-six species encountered at the Mine were native to North America (62%), including 11 taxa (7%) with rarity status in at least one New England state. Fifty-one species were non-native (33%), including nine taxa (6%) …

Survival And Recovery Following Wildfire In The Southern Range Of The Coast Redwood Forest, Rachel Lazzeri-Aerts, Will Russell

Faculty Publications, Environmental Studies

Fire plays a central role in determining structure, composition, and recruitment in many forest types. In coast redwood forests, the role of fire is not well understood and scant literature exists on post-fire response, particularly in the southern part of the range. In order to better understand patterns of survival and recruitment following fire for coast redwood (Sequoia sempervirens [lamb. ex D. Don] Endl.) and associated tree species, three sites in the Santa Cruz Mountains, California, USA, were sampled following wildfire. Randomly selected 10 m diameter plots were used to collect data on survivorship and post fire regeneration in order …

Testing Bidirectional Contextual Effects Of Adolescent Risk Factors On Young Adulthood Outcomes: A Life Course Perspective To Gangs, Andrea E. Lamont

Theses and Dissertations

Leading theories in developmental science emphasize the role of the individual as an active agent in shaping her or his environment. Yet, most empirical work has focused on unidirectional models, ultimately treating the individual as a passive recipient of environmental risk. Part of this gap between theory and analysis is methodological in nature – i.e., classical statistical methods typically do not allow for the modeling of bidirectional influences or complex longitudinal relations. Recent advancements in longitudinal methodologies, however, expand our ability to answer more nuanced developmental questions. In this dissertation, I demonstrate how advanced longitudinal methods could be used to …

The Role Of Microrna In Staphylococcal Enterotoxin B-Induced Inflammation And Acute Lung Injury, Roshni Rao

Theses and Dissertations

Staphylococcal enterotoxin B (SEB) is a potent activator of the Vβ8+T-cells leading to the proliferation of nearly 30% of the T-cell pool. As a consequence, excessive amounts of cytokine mediators are released leading to extensive tissue damage and sometimes toxic shock and death. Due to the ease with which SEB can be aerosolized anddisseminated, it is considered a biological weapon. In the current study, we investigated the pro-inflammatory effects of SEB in two mouse models of acute inflammatory lung injury. Specifically, while inflammatory cues are known to elicit changes in key transcriptional factors and gene expression, we explored for the …

Clarissa's Suffering: Theorizing Sympathy And Physical Pain In The Eighteenth Century, Audrey Hungerpiller

Theses and Dissertations

This thesis examines theories of pain in the eighteenth century, and what it meant to sympathize with the pain of another. I begin briefly with the theories of Descartes and his adherents before focusing on David Hartley and John Locke. Physicians and natural philosophers of the period understood pain as a pure mechanism of the nervous system, confined to the tubelike fibers that run through the body. Naturally everyone feels pain by some means, whether illness or injury, so men ought to be able to sympathize with the afflictions of others. Yet, according to Adam Smith in The Theory of …

Methanol And Ethanol Modulate Responses To Danger- And Microbe- Associated Molecular Patterns In Tomato, Tobacco And Arabidopsis, Claire Teresa Hann

Theses and Dissertations

Methanol is a byproduct of cell wall modification. It is released through the action of pectin methylesterases (PMEs), which demethylate cell wall pectins. Plant PMEs play not only a role in developmental processes but also in responses to herbivory and infection by fungal or microbial pathogens, resulting in increased methanol release. To break down the cell wall barrier, pathogens employ their own PMEs. Interestingly, the infection process also regulates the expression of certain plant PMEs. Methanol is toxic to a number of herbivores and reduces their fitness. At high concentrations, it upregulates signaling and defense genes. However, molecular mechanisms that …

Identifying Performance Criteria Of Fully Bioresorbable Scaffolds For Endovascular Applications, Jahid Ferdous

Theses and Dissertations

Background: Bioresorbable scaffolds (BRS) have revolutionized percutaneous coronary intervention in clinical cardiovascular medicine. As opposed to permanent alternatives such as metallic stents, BRS have an inherent potential to reduce the occurrence of untoward events such as vessel re-narrowing or thrombosis by virtue of undergoing complete and controlled resorption post- implantation. While BRS platforms demonstrate a clear potential to mitigate risk stemming from incomplete vessel healing, they introduce a new set of considerations to clinical safety and efficacy. Foremost among these issues is the fate of and biological response to material by-products that evolve throughout the scaffold degradation and erosion processes, …

A Study On Atmospheric And Oceanic Processes In The North Indian Ocean, Clifford Steven Felton

Theses and Dissertations

Studies on oceanic and atmospheric processes in the Indian Ocean are an active and important area of scientific research. Understanding how intraseasonal and interannual variations impact both the ocean and atmosphere will aid in delineating potential feedback mechanisms and global teleconnections. Thanks to recent efforts focused on expanding observational capabilities and developing models for this region, researchers have been able to begin investigating atmospheric and oceanic processes in the Indian Ocean. This study focuses on the impact of the El Niño Southern Oscillation (ENSO) on tropical cyclone activity over the Bay of Bengal (BoB) and on developing a method for …

Walking The Edge With Controversial Use Of Preimplantation Genetic Diagnosis (Pgd): Opinions And Attitudes Of Genetic Counselors, Kristen Everton

Theses and Dissertations

Purpose: This study explored opinions and attitudes of genetic counselors regarding three controversial applications of preimplantation genetic diagnosis (PGD): PGD for early-onset Alzheimer, use of embryos that are BRCA positive after PGD revealed no disease-free embryos to be available, and PGD to select against a variant of unknown significance (VUS) for Marfan syndrome. Methods: Genetic counselors were contacted through the National Society of Genetic Counselors (NSGC) electronic mailing list. Inclusion criteria required that a participant was currently practicing as a genetic counselor, was a member of the NSGC, and has counseled patients about PGD. Twenty-nine participants volunteered to participate and …

An Analysis Of Interpreter-Mediated Healthcare Interactions, Robin Dawson Estrada

Theses and Dissertations

The content and quality of communication between nurse practitioners and patients in primary care encounters contributes to diagnostic decision making, the provision of culturally appropriate interventions, and ultimately may impact health outcomes. In caring for patients with limited English proficiency, the addition of language discordance increases the complexity of the interaction and communication processes and the potential for disparate health outcomes. Most prior research on interpreter-mediated healthcare interactions has focused on accuracy, cost, satisfaction, and role enactment, but there is a lack of systematic research examining the actual interaction processes within the context of primary care clinic visits.

The aim …

Gender-Specific Instructional Strategies And Student Achievement In 5th Grade Classrooms, Millicent Whitener Dickey

Theses and Dissertations

There are three purposes of this mixed methods phenomenological case study. First, the researcher attempted to determine if there is evidence that teachers in single-sex classes adjust the delivery of the academic content when compared to coeducational classes. Secondly, while trying to understand the phenomenon of learning in a single-sex classroom, the researcher tried to determine which specific instructional strategies are considered most beneficial by male and female students. The researcher also looked for evidence of differences in achievement between students in single-sex and coeducational environments. Data collection occurred primarily through surveys, interviews, focus groups, and classroom observation over the …

Defect Mediated Electrochemical Hydrogenation Of Epitaxial Graphene: Towards Graphene Based Microbial Fuel Cells, Kevin Michael Daniels

Theses and Dissertations

Microbial fuel cells (MFCs) are seen as a promising complementary technology to alleviate the exponentially increasing worldwide energy demand. MFCs use bacteria to extract energy from biomass, where choice of electrode materials has a strong impact on energy extraction and efficiency. Graphene, a single monolayer of carbon with exceptional electrical conductivity and high surface area, is seen as a promising material with the potential of improving charge transfer and bacterial adhesion. To probe this reactivity, a novel means of hydrogenation of graphene by electrochemistry is demonstrated.

In this thesis, electrochemical hydrogenation of epitaxial graphene (EG), graphene grown on silicon carbide …

Isolation Of Natural Nrf2 Activators From American Ginseng, Akrm Abdalrahman

Theses and Dissertations

Nuclear factor erythroid-2 related factor 2 (Nrf2), a major transcription factor of the endogenous antioxidant defense system, has been proposed as a potential therapeutic target for the treatment of various diseases. However, a small molecule-driven Nrf2 signaling therapeutic approach remains to be established. Herein, we report one such possibility discovered by the bioassay-based fractionation of American ginseng. Since crude extract of American ginseng was found to suppress the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-inflamed macrophages via activating Nrf2, we further fractioned the crude extract using solvents including hexane, dichloromethane, ethyl acetate, butanol, and water, and found …

Comparative Recharge Rates Of Isolated And Riverine Wetlands, Chenille Hargrove Williams

Theses and Dissertations

Isolated wetlands have a slightly depressed topography surrounded by an upland area. There is no direct surface water connection, as with riverine wetlands; however, there is a groundwater connection that allows isolated wetlands to have similar hydrologic functions to riverine wetlands. This study sought to compare surficial aquifer groundwater recharge rates of several isolated and riverine wetlands in the Coastal Plain of the Carolinas by evaluating soil characteristics, water table fluctuations, and precipitation from January 2012 - September 2012. Data analysis indicated no significant difference in mean recharge rates between the isolated and riverine wetlands at each study site. Whereas …

Food Insecurity And Physical Activity Among U.S. Populations, Quyen G. To

Theses and Dissertations

Objectives: Examine the association between food insecurity (FI) and physical activity (PA) in the U.S. population.

Methods: Accelerometry (PAM) and self-report PA (PAQ) data from NHANES 2003-2006 were used. Those aged less than six years or were older than 65 years, pregnant, with physical limitations, or with family income above 350% of the poverty line were excluded. FI was measured by the USDA Household Food Security Survey Module. Crude and adjusted odd ratios were calculated from logistic regression to identify the association between FI and adherence to the PA recommendation. Crude and adjusted coefficients were calculated from linear regression to …

Data-Driven School Administrator Behaviors And State Report Card Results, James Alan Spencer

Theses and Dissertations

The purpose of this study was to identify the principal behaviors that would define an instructional leader as being a data-driven school administrator and to assess current school administrators' levels of being data-driven. This research attempted to examine the relationship between the degree to which a principal was data-driven and the school's performance on standardized tests and state report card values.

The research questions are:

1. To what degree do current school principals in select districts from the Charleston area of South Carolina see themselves as data-driven leaders?

2. To what extent are the 12 specific behaviors that define a …

Microbes As Proton Exchange Membranes In Microbial Fuel Cells, Andrew Timothy Stroud

Theses and Dissertations

Microbial fuel cells (MFCs) use proton exchange membranes (PEMs) to deliver protons to the cathode for electricity production. MFCs have been limited to low power generation because of complex ionic media characteristic of MFCs using the conventional Nafion-based PEM with high attraction for the competing ions. Benthic microbial fuel cells (BMFCs) use the marine sediment between the anode, embedded in marine sediment, and cathode, overlying in water, as a PEM. BMFCs have been shown to generate high power densities representing high proton permeability by the marine sediment layer between the anode and cathode. However, there is limited knowledge about this …

Comparison Of Confidence Intervals Of Intracluster Correlation Coefficient Estimates For Binary Variables, Ashok Varma Samantapudi

Theses and Dissertations

The present study evaluates the length of the confidence interval and the percentage of time the true parameter is captured by the confidence interval for four intracluster correlation estimators. These are the ANOVA estimator, the Pearson pairwise estimator with constant weights (PEQ), the kappa type estimator called FC, and an estimator using a Resampling method (RM) for binary data. We compared these different estimates by using a large simulation study. The data we simulated is correlated binary data, which assumes an exchangeable correlation structure. We also included different variations of the number of clusters, cluster size, cluster size variation, event …

Mitochondrial Replication From Embryogenesis To Early Adulthood, In Dui Species, Mytilus Galloprovincialis, Ellen Blenn Richardson

Theses and Dissertations

Eukaryotes typically inherit mitochondria strictly maternally. There are however a group of bivalve molluscs that inherit different mitochondrial genomes from each parent. The paternally inherited mtDNA (M-type) is localized to, and dominates over the maternally inherited mtDNA (F-type) in the gonads of the male offspring, but is not normally retained in any tissue of the female offspring. This process is termed Double Uniparental Inheritance (DUI). Using quantitative PCR (qPCR), this study examines mtDNA replication compared to total DNA replication through embryonic stages of development and into early adulthood of the DUI species, Mytilus galloprovincialis. Results indicate that up through the …

Best Practices In The Management Of Pediatric Obesity In Primary Care Clinics, Lori Moseley

Theses and Dissertations

Obesity prevalence among children and adolescents has nearly tripled since 1980. Children and adolescents are at risk for developing the comorbidities seen in obese and overweight adults such as hypertension, type 2 diabetes, and sleep apnea. Traditional treatment for obese and overweight children involved counseling children and their families. Current recommendations include a comprehensive staged approach to weight management that includes prevention plus structured weight management, comprehensive multidisciplinary intervention and tertiary care intervention. Unfortunately structured weight management programs have not been widely available, leaving the primary provider with limited options.

The purpose of this project was to analyze the literature …

Gestational Weight Gain And The Risk Of Obesity Among Preschool Children: Is This Mediated Through Birth Weight?, Nomathamsanqa Louise Mgutshini

Theses and Dissertations

Data from the 2001 Early Childhood Longitudinal Study Birth- Cohort were used to examine the association between maternal gestational weight gain (GWG) and the risk of obesity in the offspring, and the possible mediating role of birth weight. The Centers for Disease Control growth 2000 reference charts and child's height and weight measured at age 4 or 5 years old were used to determine child body mass index (BMI) Z-scores or obesity status (greater than or equal to the 95th percentile). Multiple linear or logistic regression models were used to adjust for maternal age, race, education, smoking status and prepregnancy …

John Pecham On Life And Mind, Caleb G. Colley

Theses and Dissertations

No abstract provided.

An Evolutionary Perspective On Infectious And Chronic Disease, John Eberth

Theses and Dissertations

The integration of evolutionary biology with traditional medicine can elucidate novel mechanisms of contemporary disease. Whereas the goal of traditional medicine is to treat and cure the proximate causes, evolutionary biology aims to understand the driving forces behind why humans are susceptible to disease. To form the basis of this hypothesis we postulate that modern man's current genetic information was programmed at a time, and in an environment, that is not relevant to today's human populations. The discordance between these genes of our ancestors and the environment of contemporary humans is thought to be a major reason for the increase …

Diethylstilbestrol (Des) Mediates Immune Suppression Via Modulation Of Microrna Expression In Mice, Martine Menard

Theses and Dissertations

Diethylstilbestrol (DES) is a synthetic compound and considered as an endocrine disruptor that interferes with the normal development of human organs and even immune tissues. DES has been investigated for its immunosuppressive effects, thymic atrophy, and various types of cancer including breast cancer, ovarian cancer, uterine cancer, etc. In this study, we investigated DES regulated mechanisms in T cells and examined whether DES exposure of T cells leads immune suppression and affects immune functions. To this end, we investigated the effect of DES on T cells in vitro and specifically examined DES-induced apoptosis in T cells, expression of genes involved …

Lead Exposure And Crime, Tara Elaine Martin

Theses and Dissertations

While lead exposure during childhood has been linked to criminal activity later in life, prior research has failed to develop a theoretical foundation explaining why lead and crime rates are positively related at the aggregate level. Utilizing tract-level data, I examine the relationship among elevated blood lead level rates, levels of concentrated disadvantage, and crime rates. Through a biosocial approach, I explore the lead-crime relationship using a measure of concentrated disadvantage to account for the variations across tracts. Finally, I discuss the results of this study as well as implications for public policy and future research.

Identification Of Clinical Markers That Predict The Outcomes Of Methicillin-Resistant Staphylococcus Aureus Infections And Identification Of Synergistic Antibiotic Combinations For The Treatment Of These Infections, Virginia Long

Master's Theses

Methicillin-resistant Staphylococcus aureus(MRSA) is a prominent nosocomial infection. Vancomycin is the mainstay of treatment, but it has a high rate of failure. Combination therapies can be used, but synergy is often not tested in clinical laboratories. Physicians are at a disadvantage because they cannot predict MRSA outcomes. The first aim of the study was to identify clinical and demographic markers that could predict infection recurrence or prolonged bacteremia. This was accomplished using retrospective chart review and statistical analysis. The second aim of the study was to identify which combinations, of those commonly used for MRSA treatment at Loyola, demonstrate the …