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Brasileirinidae, A New Isopod Family (Crustacea: Isopoda) From The Cave In Bahia (Brazil) With A Discussion On Its Taxonomic Position, Simona Prevornik, Rodrigo Lopes Ferreira, Boris Sket

KIP Articles

No abstract provided.

Multi-Partner Interactions In Corals In The Face Of Climate Change, Koty H. Sharp, Kim B. Ritchie

Arts & Sciences Faculty Publications

Recent research has explored the possibility that increased sea-surface temperatures and decreasing pH (ocean acidification) contribute to the ongoing decline of coral reef ecosystems. Within corals, a diverse microbiome exerts significant influence on biogeochemical and ecological processes, including food webs, organismal life cycles, and chemical and nutrient cycling. Microbes on coral reefs play a critical role in regulating larval recruitment, bacterial colonization, and pathogen abundance under ambient conditions, ultimately governing the overall resilience of coral reef systems. As a result, microbial processes may be involved in reef ecosystem-level responses to climate change. Developments of new molecular technologies, in addition to …

Karl E. Peace Papers, Zach S. Henderson Library Special Collections

Finding Aids

This collection consists of the personal and research papers of Karl E. Peace, Professor of Biostatistics at Georgia Southern University and namesake of the Karl E. Peace Center for Biostatistics and Survey Research. Materials span 1941 to 2018 and include, correspondence, teaching materials, published articles, and manuscripts. A small portion of 3 photographs and artists renderings are also included. This collection is still undergoing processing.

Find this collection in the University Libraries' catalog.

Whole Genome Sequencing Of Mutation Accumulation Lines Reveals A Low Mutation Rate In The Social Amoeba Dictyostelium Discoideum, Gerda Saxer, Paul Havlak, Sara A. Fox, Michael A. Quance, Sharu Gupta, Yuriy Fofanov, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Spontaneous mutations play a central role in evolution. Despite their importance, mutation rates are some of the most elusive parameters to measure in evolutionary biology. The combination of mutation accumulation (MA) experiments and whole-genome sequencing now makes it possible to estimate mutation rates by directly observing new mutations at the molecular level across the whole genome. We performed an MA experiment with the social amoeba Dictyostelium discoideum and sequenced the genomes of three randomly chosen lines using high-throughput sequencing to estimate the spontaneous mutation rate in this model organism. The mitochondrial mutation rate of 6.76×10(-9), with a Poisson confidence interval …

Why Wasp Foundresses Change Nests: Relatedness, Dominance, And Nest Quality, Perttu Seppä, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a …

Keratin 8/18 Filaments: Potential Modulators Of Death Signaling In Ovarian Granulosa Cells, Sarah E. Kinsman

Master's Theses and Capstones

Granulosa cell apoptosis is associated with follicular atresia; but the cellular mechanisms that drive this process, especially its cell specificity, are relatively unknown. Here, we determined that cultured granulosa cells abundantly express K8/K18 filaments and inhibition of protein synthesis enhances Fas-induced apoptosis. In this context, the roles of cFLIP, ERK1/2 and Akt are minimal but conversely, K8/K18 filaments have a prominent role in granulosa cell resistance to Fas-induced apoptosis. Keratin 8/18 filaments in granulosa cells provide a plausible mechanism to avoid Fas-induced apoptosis and this mechanism potentially involves the synthesis of labile proteins. The existence of K8/K18 filaments in granulosa …

The Influence Of Abiotic And Biotic Factors On Two Nudibranchs Feeding Upon Membranipora Membranacea In The Southern Gulf Of Maine, Megan I. Mcculler

Master's Theses and Capstones

The abiotic (temperature and flow rate) and biotic factors within fouling communities at three marinas located along the southern Gulf of Maine from June to December in 2010 and 2011 were surveyed. The goal of this study was to determine what is driving the recent population increase of the nudibranch, Corambe obscura, and whether the native nudibranch, Onchidoris muricata, is transitioning prey species. In addition, the affects of temperature on aspects of C. obscura's life history were determined by laboratory experiments.

Results suggest that abiotic factors influence basic community members such as the kelp host, Saccharina latissima, and the invasive …

Full Issue: Volume 6, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.

The Role Of Autophagy And Il-17 In Bone Resorption, Carl Deselm

All Theses and Dissertations (ETDs)

Osteoclasts are essential for skeletal homeostasis: Teitelbaum, 2000). These macrophage-lineage cells function by generating a polarized microenvironment between themselves and bone wherein skeletal matrix is degraded. This resorptive compartment is isolated from the general extracellular space by an actin ring which encompasses the ruffled border, a convoluted plasma membrane structure formed by its fusion with lysosome-related vesicles containing an electrogenic H+ATPase, a chloride channel, LAMP-1, and cathepsin K. In consequence, resorption of bone reflects secretion of HCl to mobilize mineral, and cathepsin K to degrade the collagen-rich organic matrix, into the resorptive space: Stenbeck, 2002; Zhao et al., 2008). We …

Atm Deficiency -- A Multifaceted Defect In Lymphocyte Development, Beth Helmink

All Theses and Dissertations (ETDs)

The generation of a functional antigen receptor gene in developing lymphocytes requires that the second exon be assembled through a process known as V(D)J recombination, a process that necessarily involves the generation and repair of DNA double-strand breaks made by the Rag endonuclease. Double strand breaks incurred during G1 of the cell cycle activate ATM, a PI3-kinase-like kinase that, in response to genotoxic DNA damage, is known to phosphorylate hundreds of proteins with unique and diverse functions. Notably, deficiencies in ATM lead to ataxia-telangiectasia, a syndrome characterized by lymphopenia, genomic instability and a predisposition to tumors involving antigen receptor loci …

Joint Functions Of Mett-10 And Dynein In The Caenorhabditis Elegans Germ Line, Maia Dorsett

All Theses and Dissertations (ETDs)

During normal development as well as in diseased states such as cancer, extracellular "niches" often provide cues to proximal cells and activate intracellular pathways. Activation of such signaling pathways in turn instructs cellular proliferation and differentiation. In the C.elegans gonad, GLP-1/Notch signaling instructs germ line stem cells to self renew through mitotic cell division. As germ cells progressively move out of the niche, they differentiate by entering meiosis and eventually form gametes. Using this model system, I uncovered a cooperative role for the METT-10 putative methyltransferase and the dynein motor complex in regulating the balance between germ cell proliferation and …

Monitoring Occupancy And Abundance Of New England Cottontails Using Non-Invasive Genetic Tools, Daniel Brubaker

Master's Theses and Capstones

The New England cottontail (Sylvilagus transitionalis ) is a species of conservation concern. Efficient monitoring methods are needed to guide and assess conservation decisions in an adaptive management framework. I used genetic tools and non-invasively collected fecal DNA to determine New England cottontail detection rates during presence/absence surveys and to identify the environmental and behavioral factors that influence detection.

I found New England cottontail detection rates to be high (>90%) when surveys were conducted under ideal conditions. Prior knowledge of cottontail activity, low snow depth, and allowing 2-4 days without high winds following a snowfall are the most important …

Field And Laboratory Observations Of Two Gulf Of Maine Sacoglossans, Seth W. Goodnight

Master's Theses and Capstones

The ecology of the sacoglossan Alderia modesta and its ability to retain active chloroplasts from the yellow-green alga Vaucheria spp. was examined with field and laboratory studies. Field surveys found no A. modesta, because Vaucheria spp. was absent or sparse in surveyed marshes. A grass removal experiment tested whether interspecific competition was causing the algal absence. The alga appeared in some plots, but did not promote A. modesta settlement. Absence of Vaucheria spp. is likely due to factors other than competition. Lack of animals prevented laboratory studies.

Placida dendritica and its food Codium fragile ssp. fragile were then chosen for …

Cryopreservation Spermiation Induction And Computer Assisted Analysis Of Summer Flounder (Paralicthys Dentatus) Spermatozoa, Ryan T. Brown

Master's Theses and Capstones

The objective of this thesis was to improve the aquaculture practices for summer flounder Paralichthys dentatus. The experiments in this thesis examined male reproduction. First a practical method for summer flounder sperm cryopreservation was developed. These experiments examined the various parameters required to successfully freeze and store summer flounder spermatozoa. Success of cryopreservation was measured by examining post thaw viability and fertility.

One of the problems facing summer flounder aquaculture is sexually dimorphic growth rates, with females growing larger than males. To overcome this, meiogynogenetic summer flounder were developed, allowing the production of all female stocks. The second set of …

A Comparison Of Standard And Ventless American Lobster Trap Dynamics, Abigail S. Clark

Master's Theses and Capstones

The American lobster, Homarus americanus, is the most valuable marine resource in New England and, as with any fishery, effective management depends on accurate stock assessment. The purpose of this study was to examine the efficacy of standard and ventless traps, focusing on determining which trap provides a better index of lobster abundance. While ventless traps caught approximately five times as many lobsters as standard traps, the size of captured lobsters did not differ significantly between trap types. Ventless traps saturated after 16 - 24 hours, but standard traps did not saturate at all. Despite saturating at all densities, ventless …

The Role Of Eelgrass (Zostera Marina L) Source Population Characteristics In Resilience To Stress And Restoration Success, Holly K. Bayley

Master's Theses and Capstones

Eelgrass (Zostera marina L.), an underwater marine flowering plant, has a high degree of morphological plasticity that allows it to survive and grow under a range of conditions and adapt to environmental changes. The degree to which resilience to stress varies among eelgrass populations is important for eelgrass conservation and management. Eelgrass plants from ten genetically differentiated populations were used in a mesocosm experiment where light availability and sediment organic content were manipulated. Productivity and survival were inhibited and morphology was altered by the stress treatments, with these plant responses differing significantly among populations. To further test differences in resilience, …

Adaptation Of A Pseudomonas Aeruginosa Population To A Biofilm Lifestyle: Why Is Polyphosphate Kinase Important?, Keith Ferguson

Master's Theses and Capstones

In the environment, bacterial populations often exist as communities called biofilms. During this sessile state, bacteria excrete exopolysaccharides that form a sticky, protective matrix. This protective matrix also presents a prominent medical challenge since chronic infections of cystic fibrosis (CF) patients are commonly biofilm associated. Pseudomonas aeruginosa is one bacterium that can colonize the CF lung and persist in a biofilm community. During chronic infections, P. aeruginosa adapts to its lung environment and displays genetic and phenotypic diversification. To model evolution during chronic infections, biofilm populations were experimentally evolved for 540 generations and the genetic variation was sampled at 100, …

The Status Of Five State-Listed Tidal Plant Species In New Hampshire With Emphasis On Potential Impacts Of Sea Level Rise, Lauren A. Kras

Master's Theses and Capstones

Tidal habitat in New Hampshire is restricted to 162 miles along coasts and estuaries. Limited area combined with anthropogenic impacts has caused 27 tidal plant species to be listed as threatened or endangered. In 2009 and 2010, the status of four threatened species: Eleocharis parvula, Samolus valerandi, Lilaeopsis chinensis , and Agalinis maritima and one endangered species Salicornia bigelovii was examined. To guide management and conservation, the historic and current distributions were compared and habitat features were determined. All five species were stable; however, S. valerandi and L. chinensis appear threatened by sea level rise and coastal squeeze as they …

The Effect Of Superman, Agamous, And Acs-7 Gene Manipulations On Sex Determination In Transgenic Fragaria Vesca 'Hawaii-4', Xin Ding

Master's Theses and Capstones

Sex determination is of interest to plant breeders who transfer useful genes from wild relatives to the cultivated strawberry. The potential roles in sex determination of seven candidate genes, which included five SUPERMAN genes, the AGAMOUS gene, and the ACS-7 gene, were studied by re-introducing them into diploid strawberry as overexpression and RNAi constructs by Agrobacterium-mediated transformation. All of the transgenic calli expressed the GFP fluorescence marker. Among regenerated plants, some AGAMOUS-silenced plants transiently displayed a petalloid stamen or a vestigial petal phenotype, pointing to the AGAMOUS gene as negative regulator of A- and B-class genes according to the widely …

Hemoglobin Type, Egg Buoyancy, And Antifreeze Glycoprotein Production As Mechanisms For Adaptive Variation In Gulf Of Maine Atlantic Cod (Gadus Morhua), Amanda R. Clapp

Master's Theses and Capstones

Three physiological traits were examined to compare captive populations of winter- and spring-spawning cod from the Gulf of Maine, as differences in these traits have been observed in other locally-adapted subpopulations. Daily mean neutral buoyancy of hatchery-spawned eggs was observed at three temperatures (5, 10, and 12°C) and three photoperiods (15:9, 9:15, and 24:0 L: D) at 12°C. Body fluids of larvae held at 0°C for five days were tested for antifreeze glycoproteins (AFGPs) to determine the onset of AFGP production. Juveniles held at 0°C were bled between 20 and 35 days to determine induction time for AFGP production. Hemoglobin …

Activity Rhythms Expressed By Juvenile American Horseshoe Crabs, Limulus Polyphemus, Elizabeth Anne Dubofsky

Master's Theses and Capstones

The goals of this study were to determine if juvenile horseshoe crabs, Limulus polyphemus, express daily or tidal patterns of activity and how light and tidal cycles influence these patterns. When exposed to a light:dark cycle (n=24), 63% of juveniles exhibit daily patterns of locomotion and 25% of juveniles express circatidal patterns. When subsequently exposed to constant darkness, 17% express circadian rhythms of activity, 25% express a combination of circadian and circatidal patterns, and 46% express circatidal patterns of activity. When exposed to tidal cycles (n=42), 55% of juveniles express tidal patterns of activity, while the remainder exhibit either a …

Microsatellite And Mitochondrial Dna Analysis Of Dungeness Crab (Cancer Magister) From California To Northern British Columbia, Bryan Thomas Barney

Master's Theses

Genetic variation was assessed using mitochondrial DNA and microsatellite markers from Dungeness crab between Iceberg Bay, British Columbia and San Luis Obispo, California. We found little pattern in overall genetic variation between sites in both marker types, and no significant Isolation by Distance model was fit. Site-specific variation in mitochondrial DNA haplotype frequencies suggested the existence of three subpopulations associated with the Alaska Current, the Puget Sound, and the California Current, but microsatellite DNA evidence did not support it. The ratio between sampling size for microsatellite markers and fragment size polymorphisms was low, limiting the resolving power of microsatellite DNA …

Biology And Nursing Students’ Perceptions Of A Web-Based Information Literacy Tutorial, Sharon A. Weiner, Nancy Pelaez, Karen Chang, John M. Weiner

Libraries Faculty and Staff Scholarship and Research

This study examined the perceptions of two groups of students to obtain different perspectives on the online information literacy tutorial, CORE (Comprehensive Online Research Education, to plan for its update. The CORE tutorial includes seven modules: “Planning Your Project,” “Topic Exploration,” “Types of Information,” “Search Tools,” “Search Strategies,” “Evaluating Sources,” and “Copyright, Plagiarism, and Citing Sources.” First-year students in biology and nursing courses responded to a survey after completing the CORE modules. Students indicated that they liked learning through an online tutorial. However, they thought that the tutorial could be improved with shorter modules and the addition of video and …

Diversity And Dynamics Of Bacterial Communities In Early Life Stages Of The Caribbean Coral Porites Astreoides, Koty H. Sharp, Dan Distel, Valerie J. Paul

Arts & Sciences Faculty Publications

In this study, we examine microbial communities of early developmental stages of the coral Porites astreoides by sequence analysis of cloned 16S rRNA genes, terminal restriction fragment length polymorphism (TRFLP), and fluorescence in situ hybridization (FISH) imaging. Bacteria are associated with the ectoderm layer in newly released planula larvae, in 4-day-old planulae, and on the newly forming mesenteries surrounding developing septa in juvenile polyps after settlement. Roseobacter clade-associated (RCA) bacteria and Marinobacter sp. are consistently detected in specimens of P. astreoides spanning three early developmental stages, two locations in the Caribbean and 3 years of collection. Multi-response permutation procedures analysis …

Brown Treesnakes: A Potential Invasive Species For The United States, Samantha Sue Kahl, Scott E. Henke, Marc A. Hall, David K. Britton

Human–Wildlife Interactions

Brown treesnakes (ˆ) are mildly venomous, exotic snakes that have the potential to become an invasive species in North America, Hawaii, and the Commonwealth of the Northern Mariana Islands. The snake is native to northern and eastern Australia, New Guinea, and other islands of northern and western Melanesia. The snakes were first found outside their native range on Guam in 1953. The exact date they reached the island is uncertain, but they are believed to have arrived on military cargo transport vessels some time during or just after World War II. During the years that followed, the population of brown …

Structured Growth And Genetic Drift Raise Relatedness In The Social Amoeba Dictyostelium Discoideum, Neil J. Buttery, Chandra N. Jack, Boahemaa Adu-Oppong, Kate T. Snyder, Christoper R L Thompson, David C. Queller, Joan E. Strassmann

Biology Faculty Research

One condition for the evolution of altruism is genetic relatedness between altruist and beneficiary, often achieved through active kin recognition. Here, we investigate the power of a passive process resulting from genetic drift during population growth in the social amoeba Dictyostelium discoideum. We put labelled and unlabelled cells of the same clone in the centre of a plate, and allowed them to proliferate outward. Zones formed by genetic drift owing to the small population of actively growing cells at the colony edge. We also found that single cells could form zones of high relatedness. Relatedness increased at a significantly …

Mind The Gap: A Comparative Study Of Migratory Behavior In Social Amoebae, Owen M. Gilbert, Jennie J. Kuzdzal-Fick, David C. Queller, Joan E. Strassmann

Biology Faculty Research

Social amoebae aggregate to form a multicellular slug that migrates some distance. Most species produce a stalk during migration, but some do not. We show that Dictyostelium giganteum, a species that produces stalk during migration, is able to traverse small gaps and utilize bacterial resources following gap traversal by shedding live cells. In contrast, we found that Dictyostelium discoideum, a species that does not produce stalk during migration, can traverse gaps only when in the presence of other species’ stalks or other thin filaments. These findings suggest that production of stalk during migration allows traversal of gaps that commonly occurs …

Functional Analysis Of Conserved Motifs In The Mechanosensitive Channel Homolog Mscs-Like2 From Arabidopsis Thaliana, Gregory S. Jensen, Elizabeth S. Haswell

Biology Faculty Research

The Mechanosensitive channel of Small conductance (MscS) of Escherichia coli has become an excellent model system for the structural, biophysical, and functional study of mechanosensitive ion channels. MscS, a complex channel with multiple states, contributes to protection against lysis upon osmotic downshock. MscS homologs are widely and abundantly dispersed among the bacterial and plant lineages, but are not found in animals. Investigation into the eukaryotic branch of the MscS family is in the beginning stages, and it remains unclear how much MscS homologs from eukaryotes resemble E. coli MscS with respect to structure, function, and regulation. Here we test the …

Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Protein sequences are normally the most conserved elements of genomes owing to purifying selection to maintain their functions. We document an extraordinary amount of within-species protein sequence variation in the model eukaryote Dictyostelium discoideum stemming from triplet DNA repeats coding for long strings of single amino acids. D. discoideum has a very large number of such strings, many of which are polyglutamine repeats, the same sequence that causes various human neurological disorders in humans, like Huntington’s disease. We show here that D. discoideum coding repeat loci are highly variable among individuals, making D. discoideum a candidate for the most variable …

Manipulation Of Angiogenesis By Cyclosporine-A And Extracellular Matrix Molecules, Raghav Pandey

All-Inclusive List of Electronic Theses and Dissertations

Angiogenesis is the formation of new capillaries from pre-existing capillaries. Angiogenesis plays an important role in the blood vessel formation required during embryonic development, tissue injury, wound healing, and menstruation. It also plays a major role in tumor progression. We propose a mechanism that links the developmental pathways to a therapeutic pathway. Moreover, we show anti-angiogenic nature of an FDA approved immunosuppressant. Extra cellular matrix (ECM) has an important role in maintaining the shape and structure of organisms and in signaling mechanisms. Two major components of ECM are lumican and Magp2. Investigating their role might help us further link angiogenesis …