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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 Jan 2013

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 Jan 2013

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 Jan 2013

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 …


Characterization Of The Prokaryotic Community Associated With The Giant Barrel Sponge, Xestospongia Muta Across The Caribbean, Cara L. Fiore Jan 2013

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 Jan 2013

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 Jan 2013

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 Jan 2013

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 Jan 2013

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 Jan 2013

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. …


Biology And Ecology Of Glyphosate-Resistant Giant Ragweed, Kabelo Segobye Jan 2013

Biology And Ecology Of Glyphosate-Resistant Giant Ragweed, Kabelo Segobye

Open Access Theses

Giant ragweed (Ambrosia trifida L.) is a competitive annual plant found in disturbed landscapes and is the most troublesome weed in Indiana and the US Corn Belt. It is one of the most common and problematic weeds in corn and soybean production. The introduction of herbicide glyphosate, N-(phosphonomethyl) glycine in early 1970's provided farmers with a better and low-cost tool to control weeds. The use of glyphosate drastically increased after the development of glyphosate resistant agronomic crops in 1996 and was use as a post-emergence selective herbicide. This led to overreliance and repeated use of glyphosate for weed control especially …


What Real-World Criminal Cases Tell Us About Genetics Evidence, Deborah W. Denno Jan 2013

What Real-World Criminal Cases Tell Us About Genetics Evidence, Deborah W. Denno

Faculty Scholarship

This Article, which is part of a symposium on "Law and Ethics at the Frontier of Genetic Technology," examines an unprecedented experimental study published in Science. The Science study indicated that psychopathic criminal offenders were more likely to receive lighter sentences if a judge was aware of genetic and neurobiological explanations for the offender’s psychopathy. This Article contends that the study’s conclusions derive from substantial flaws in the study’s design and methodology. The hypothetical case upon which the study is based captures just one narrow and unrepresentative component of how genetic and neurobiological information operates, and the study suffers from …


Dynamic Passivation With Bsa Overcomes Ltcc Mediated Inhibition Of Pcr, Jason Besecker, Kenneth A. Cornell, Greg Hampikian Jan 2013

Dynamic Passivation With Bsa Overcomes Ltcc Mediated Inhibition Of Pcr, Jason Besecker, Kenneth A. Cornell, Greg Hampikian

Chemistry and Biochemistry Faculty Publications and Presentations

The increasing use of low temperature co-fired ceramic (LTCC) for the fabrication of biological microfluidic devices necessitates further research on LTCC biocompatibility. In this study we explore the inhibitory effect of DuPont's 951 LTCC on Polymerase Chain Reaction (PCR), and demonstrate a novel mechanism to increase biocompatibility between LTCC and PCR with the addition of a common passivation substance, bovine serum albumin (BSA). We show that DuPont's 951 LTCC binds negatively charged proteins including BSA and ovalbumin (OVA). This is a significant discovery as proteins (enzymes) are an essential component of most biological reactions, and a frequent addition to microfluidic …


Full Issue: Volume 6, Number 2 Jan 2013

Full Issue: Volume 6, Number 2

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


Full Issue: Volume 7, Number 1 Jan 2013

Full Issue: Volume 7, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


Productivity And Physical Condition Of White-Tailed Deer In New Hampshire, Nicholas Lucian Fortin Jan 2013

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 …


Evaluating Phenotypic Differences Between High Tunnel Tomato Cultivars And The Functional Role Of Diversity In A Broccoli - Living Mulch Agroecostytem, Nicholas Warren Jan 2013

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 …


Characterizing Winter Flounder (Pseudopleuronectes Americanus) Nursery Areas Using Otolith Microstructure And Microchemical Techniques, David Bailey Jan 2013

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 Jan 2013

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 Jan 2013

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 Jan 2013

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 …


Patterns Of Intron Loss And Gain In Caenorhabditis, Gabrielle Giese Jan 2013

Patterns Of Intron Loss And Gain In Caenorhabditis, Gabrielle Giese

Master's Theses and Capstones

Introns, segments of genes that get spliced from the transcript before translation, are prevalent parts of many genomes and yet remain largely mysterious. Although their presence in the genome has been known for over thirty years, we still cannot answer the most fundamental questions about introns, such as where did they originate and, how are they gained and lost? In our most stringent dataset, we compared 137,453 intron positions in 6,257 pan-orthologs among four species of Caenorhabditis using a bioinformatics approach. While 82% of intron positions were conserved, we found a remarkable amount of intron variation. We also found evidence …


Ecology And Management Of Moose In Northern New England, Haley A. Andreozzi Jan 2013

Ecology And Management Of Moose In Northern New England, Haley A. Andreozzi

Master's Theses and Capstones

This study examined three facets of moose ecology in northern New England: impact of moose browsing on forest regeneration, physical characteristics of harvested bull moose, and winter habitat use. Forest regeneration was not considered a major problem in northern Vermont based on stocking levels of commercial tree species. Increasing dominance of softwood species coupled with suppressed growth of hardwoods suggests possible local shifts in composition. Bull moose in Maine had stable body weight and antler spread, and selective harvest of trophy bulls was not apparent over 30 years. Winter locations from aerial surveys indicated that moose preferentially used deciduous/mixed forest …


Introduction: Men, Masculinities, And Law: A Symposium On Mutlidimensional Masculinities Theory, Ann C. Mcginley Jan 2013

Introduction: Men, Masculinities, And Law: A Symposium On Mutlidimensional Masculinities Theory, Ann C. Mcginley

Scholarly Works

No abstract provided.


Taxonomy And Systematics Of New Zealand Faronitae (Coleoptera: Staphylinidae: Pselaphinae), Jong-Seok Park Jan 2013

Taxonomy And Systematics Of New Zealand Faronitae (Coleoptera: Staphylinidae: Pselaphinae), Jong-Seok Park

LSU Doctoral Dissertations

The New Zealand Faronitae was revised at the species level, and a phylogenetic study was performed based on morphological and molecular data. Eight new genera and 143 new species were discovered. Three new genera, “Brounea”, “Ahnea” and “Pseudoexeirarthra” were designated based on the species originally described in the genus Sagola. Five new genera, “Aucklandea”, “Chandlerea”, “Nunnea”, “Leschenea” and “Pseudostenosagola” were designated by new species. Three known genera, Exeirarthra, Stenosagola and Sagola were also revised at species level. Eighty four names were synonymized, two in Exeirarthra, four in Stenosagola and 78 in Sagola. Lectotypes of seven species, Sagola terricola Broun, S. …


The Effect Of Teaching Biology Concepts With Animations Compared To Static Cartoons On Content Retention, Rebecca Adams Polk Jan 2013

The Effect Of Teaching Biology Concepts With Animations Compared To Static Cartoons On Content Retention, Rebecca Adams Polk

LSU Master's Theses

This study explores the effect of animations versus static cartoons on students’ content retention in a high school biology classroom. Students were pre-tested prior to the introduction of content in three units of study: cellular transport, protein synthesis, and mitosis. After instruction on the topic via PowerPoint presentations, students were randomly assigned to either the test group or experimental group for each unit. The control group was removed from the room and given a series of static cartoons with captions to view. The experimental group viewed an animation on the topic, accompanied by teacher narration, which consisted of the captions …


A Bacterial Symbiont Is Converted From An Inedible Producer Of Beneficial Molecules Into Food By A Single Mutation In The Gaca Gene, Pierre Stallforth, Debra A. Brock, Alexandra M. Cantley, Xiangjun Tian, David C. Queller, Joan E. Strassmann, Jon Clardy Jan 2013

A Bacterial Symbiont Is Converted From An Inedible Producer Of Beneficial Molecules Into Food By A Single Mutation In The Gaca Gene, Pierre Stallforth, Debra A. Brock, Alexandra M. Cantley, Xiangjun Tian, David C. Queller, Joan E. Strassmann, Jon Clardy

Biology Faculty Research

Stable multipartite mutualistic associations require that all partners benefit. We show that a single mutational step is sufficient to turn a symbiotic bacterium from an inedible but host-beneficial secondary metabolite producer into a host food source. The bacteria's host is a "farmer" clone of the social amoeba Dictyostelium discoideum that carries and disperses bacteria during its spore stage. Associated with the farmer are two strains of Pseudomonas fluorescens, only one of which serves as a food source. The other strain produces diffusible small molecules: pyrrolnitrin, a known antifungal agent, and a chromene that potently enhances the farmer's spore production and …


“Culling The Herd”: Eugenics And The Conservation Movement In The United States, 1900–1940, Garland E. Allen Jan 2013

“Culling The Herd”: Eugenics And The Conservation Movement In The United States, 1900–1940, Garland E. Allen

Biology Faculty Research

While from a late twentieth- and early twenty-first century perspective, the ideologies of eugenics (controlled reproduction to eliminate the genetically unfit and promote the reproduction of the genetically fit) and environmental conservation and preservation, may seem incompatible, they were promoted simultaneously by a number of figures in the progressive era in the decades between 1900 and 1950. Common to the two movements were the desire to preserve the ‘‘best’’ in both the germ plasm of the human population and natural environments (including not only natural resources, but also undisturbed nature preserves such as state and national parks and forests). In …


Aaron Gillette , Eugenics And The Nature Nurture Debate In The Twentieth Century, Garland E. Allen Jan 2013

Aaron Gillette , Eugenics And The Nature Nurture Debate In The Twentieth Century, Garland E. Allen

Biology Faculty Research

Aaron Gillette, Eugenics and the Nature–Nurture Debate in the Twentieth Century, Palgrave Studies in the History of Science and Technology [2007], digital reprint (New York, NY: Palgrave Macmillan, 2010), pp. ix, 239, index, £18.99, paperback, ISBN: 9780230108455. This book treats an important subject – the history of the nature–nurture debate (focused on the US but with references to European players and movements) – and its implications for current theories of evolutionary psychology.


Greater Sexual Reproduction Contributes To Differences In Demography Of Invasive Plants And Their Noninvasive Relatives, Jean H. Burns, Eleanor A. Pardini, Michele R. Schutzenhofer, Y Anny Chung, Katie J. Seidler, Tiffany M. Knight Jan 2013

Greater Sexual Reproduction Contributes To Differences In Demography Of Invasive Plants And Their Noninvasive Relatives, Jean H. Burns, Eleanor A. Pardini, Michele R. Schutzenhofer, Y Anny Chung, Katie J. Seidler, Tiffany M. Knight

Biology Faculty Research

An understanding of the demographic processes contributing to invasions would improve our mechanistic understanding of the invasion process and improve the efficiency of prevention and control efforts. However, field comparisons of the demography of invasive and noninvasive species have not previously been conducted. We compared the in situ demography of 17 introduced plant species in St. Louis, Missouri, USA, to contrast the demographic patterns of invasive species with their less invasive relatives across a broad sample of angiosperms. Using herbarium records to estimate spread rates, we found higher maximum spread rates in the landscape for species classified a priori as …


A New Social Gene In Dictyostelium Discoideum, Chtb, Lorenzo A. Santorelli, Adam Kuspa, Gad Shaulsky, David C. Queller, Joan E. Strassmann Jan 2013

A New Social Gene In Dictyostelium Discoideum, Chtb, Lorenzo A. Santorelli, Adam Kuspa, Gad Shaulsky, David C. Queller, Joan E. Strassmann

Biology Faculty Research

BACKGROUND:

Competitive social interactions are ubiquitous in nature, but their genetic basis is difficult to determine. Much can be learned from single gene knockouts in a eukaryote microbe. The mutants can be competed with the parent to discern the social impact of that specific gene. Dictyostelium discoideum is a social amoeba that exhibits cooperative behavior in the construction of a multicellular fruiting body. It is a good model organism to study the genetic basis of cooperation since it has a sequenced genome and it is amenable to genetic manipulation. When two strains of D. discoideum are mixed, a cheater strain …