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Evaluation Of Post Harvest Conditions Contributing To Attacks By The Red Turpentine Beetle, Dendroctonus Valens Leconte At The Massabesic Experimental Forest In Southern Maine, Garret D. Dubois

Master's Theses and Capstones

Silvicultural management of Pinus strobus L. runs the risk of damaging residual trees and can increase the probability of attack from damaging insects, including the common bark beetle Dendroctonus valens Le Conte. Considered a secondary pest, it is possible that D. valens is capable of economic impacts such as the downgrading of logs and lumber due to defect and blue-stain. To assess post harvest conditions that contribute to the probability and severity of D. valens attacks in Pinus strobus, stand and tree characteristics were sampled in four silvicultural treatments and one control site in southern Maine. Results showed that clearcuts …

Using Pentaploids As Tools For Studying Genomic Composition And Allele Transmission Patterns In Octoploid Fragaria, Elizabeth Poulsen

Master's Theses and Capstones

A unique pentaploid population of Fragaria (strawberry) was developed to gain insight into octoploid genome composition and allele transmission patterns. This population was produced by crossing representatives of two divergent subspecies of octoploid F. virginiana and then by crossing an octoploid hybrid plant with diploid F. vesca. To enable examination of allele transmission patterns, the intergenic region of the gRGA1-Subtilase gene pair locus was amplified, and PCR products were cloned, sequenced, and compared to define the allele composition of the hybrid octoploid. The sequencing data revealed three distinct major haplotypes and additional subtypes. The pentaploids were genotyped utilizing the FEL-CAPS …

Impacts Of Suburbanization On Food Web Stoichiometry Of Detritus-Based Streams, Nathaniel Burr Morse

Master's Theses and Capstones

Higher non-point source nutrient inputs are one of many impacts associated with the "urban stream syndrome". Research on how non-point source pollution affects the stoichiometry of urban stream food webs has received little attention, however. This study quantified food web stoichiometry in nine headwater, detritus-based streams draining forested or suburban watersheds in northeastern, coastal Massachusetts.

While this study suggests that suburbanization can affect in-stream nutrient recycling by consumers, research that quantifies changes to biomass of different in-stream compartments is needed to calculate the extent of such impacts on suburban stream ecosystems.

A Three-Dimensional Computer Simulation Model Reveals The Mechanisms For Self-Organization Of Plant Cortical Microtubules Into Oblique Arrays, Ezgi Can Eren, Ram Dixit, Natarajan Gautam

Biology Faculty Research

The noncentrosomal cortical microtubules (CMTs) of plant cells self-organize into a parallel three-dimensional (3D) array that is oriented transverse to the cell elongation axis in wild-type plants and is oblique in some of the mutants that show twisted growth. To study the mechanisms of CMT array organization, we developed a 3D computer simulation model based on experimentally observed properties of CMTs. Our computer model accurately mimics transverse array organization and other fundamental properties of CMTs observed in rapidly elongating wild-type cells as well as the defective CMT phenotypes observed in the Arabidopsis mor1-1 and fra2 mutants. We found that CMT …

Seed Dispersal By Pulp Consumers, Not ‘‘Legitimate’’ Seed Dispersers, Increases Guettarda Viburnoides Population Growth, Andrea P. Loayza, Tiffany M. Knight

Biology Faculty Research

We examined the effect of seed dispersal by Purplish Jays (Cyanocorax cyanomelas; pulp consumers) and the Chestnut-eared Araçari (Pteroglossus castanotis; "legitimate" seed dispersers) on population growth of the small tree Guettarda viburnoides (Rubiaceae) in northeastern Bolivian savannas. Because each bird species differs with respect to feeding and post-feeding behavior, we hypothesized that seed dispersal by each species will contribute differently to the rate of increase of G. viburnoides, but that seed dispersal by either species will increase population growth when compared to a scenario with no seed dispersal. To examine the effects of individual dispersers on the future population size …

Review Of The Species Of Gugolzia Delucchi And Steffan (Hymenoptera: Pteromalidae) In Europe And Turkey, With Descriptions Of New Species, Mi̇kdat Doğanlar, Oğuzhan Doğanlar

Turkish Journal of Zoology

The species of Gugolzia (Hymenoptera: Chalcidoidea, Pteromalidae) in Europe and Turkey were reviewed, and an identification key for differentiating the species is provided. Newly discovered diagnostic characters of the genus were added to the diagnoses given by earlier authors. Species were recorded as parasitoids of phytophagous Eurytomidae (Hymenoptera: Chalcidoidea). New host and distributions are for Gugolzia harmolitae, which was reared from Tetramesa romana feeding on shoots of Arundo donax (Poaceae), Gugolzia karadagae n.sp. from Eurytoma plotnikovi feeding on fruits of Pistacia vera together with Megastigmus pistaciae (Chalcidoidea: Torymidae) in Gaziantep province, and Gugolzia melengicia n.sp. from fruits of Pistacia terebinthi …

Apparent Competition With An Invasive Plant Hastens The Extinction Of An Endangered Lupine, Emily M. Dangremond, Eleanor A. Pardini, Tiffany M. Knight

Biology Faculty Research

Invasive plants may compete with native plants by increasing the pressure of native consumers, a mechanism known as "apparent competition." Apparent competition can be as strong as or stronger than direct competition, but the role of apparent competition has rarely been examined in biological invasions. We used four years of demographic data and seed-removal experiments to determine if introduced grasses caused elevated levels of seed consumption on native plant species in a coastal dune system in California, USA. We show that the endangered, coastal dune plant Lupinus tidestromii experiences high levels of pre-dispersal seed consumption by the native rodent Peromyscus …

Neurophysiological Adaptations To Resistance Training And Repetitive Grasping, Michael Falvo

All Theses and Dissertations (ETDs)

Perhaps the most prominent feature of the central nervous system is its ability to respond to experience and its environment. Understanding the processes and mechanisms that govern adaptive behavior provides insights into its plastic nature. Capitalizing on this plasticity is of critical importance in response to injury and recovery: 35, 106), and the importance of its promotion is increasingly recognized by rehabilitation scientists. Neurophysiological techniques permitting study of cortical function in vivo may play a significant role in validating exercise interventions and disease management approaches: 14). It may be possible that with these advances we may better understand the relationship …

Proteomics Assisted Discovery Of Novel Proteins In Assembly And Regulation Of Photosystem Ii, Kimberly Wegener

All Theses and Dissertations (ETDs)

Cyanobacteria, the only prokaryotes capable of oxygenic photosynthesis, are present in diverse ecological niches and play crucial roles in global carbon and nitrogen cycles. To proliferate in nature, cyanobacteria utilize a host of stress responses to maintain photosynthesis under periodic changes in environmental conditions. Recent advances in proteomic study have enabled a systems-level analysis of cellular functions in many systems. Because proteins are directly responsible for cellular functions, measurements of protein abundances provide significant clues to the modulation of cellular functions during different environmental perturbations. A detailed knowledge of the composition of, as well as the dynamic changes in, the …

The Role Of Mda5 And Tlr3 In Response To Dsrna And Viral Infection, Stephen Mccartney

All Theses and Dissertations (ETDs)

The innate immune system consists of a number of genetically encoded receptors that detect the products of viral replication and initiate signaling cascades leading to activation of the antiviral response. During the course of infection, many viruses produce dsRNA that can be recognized by two major arms of the innate immune system: the toll-like receptors: TLR) and the Rig-I-like receptors: RLR). Among the TLRs, TLR3 binds dsRNA within the endosomal compartment and initiates signaling through its downstream adapter TRIF. Melanoma differentiation-induced gene 5: MDA5) is a member of the RLR family that recognizes dsRNA within the cytosolic compartment and signals …

The Effects Of Habitat Corridors And Edges On Sources Of Seed Mortality: Implications For Restoring A Threatened Legume, Melissa Simon

All Theses and Dissertations (ETDs)

No abstract provided.

Regulation Of Peripheral Nerve Regeneration By The Mtor Pathway, Namiko Abe

All Theses and Dissertations (ETDs)

While neurons in the central nervous system: CNS) have limited capacity for regrowth after damage, neurons in the peripheral nervous system: PNS) have a robust ability to regenerate their axons following injury. Successful regeneration depends upon both extrinsic cues in the environment and the activation of intrinsic mechanisms to promote regrowth. A number of inhibitory molecules in the CNS environment that prevent axonal regrowth have been identified, but less is known regarding the signaling mechanisms that regulate regenerative ability in PNS neurons. Here, we explored multiple components of injury signaling in the PNS, including the retrograde transport of local axonal …

Ionic Mechanisms Of Action Potential Rate Dependence, Conduction And Block In Normal Epicardium And In Remodeled Epicardium Post-Infarction, Keith Decker

All Theses and Dissertations (ETDs)

In this work, detailed computational models are used to study the electrophysiology of normal epicardium and the arrhythmogenic effects of epicardial cell remodeling post-infarction. The canine epicardial myocyte model described here reproduces a wide range of experimentally observed rate dependent phenomena in cell and tissue. Model behavior depends on updated formulations for the 4-AP sensitive transient outward current: Ito1), the slow component of the delayed rectifier potassium current: IKs), the L-type Ca2+ channel: ICa,L) and the sodium-potassium pump: INaK) fit to data from canine ventricular myocytes. The model shows that Ito1 plays a limited role in potentiating peak ICa,L and …

Role Of The Ajuba Lim Proteins In Epithelial Growth Regulation, Meghna Das Thakur

All Theses and Dissertations (ETDs)

The mammalian Ajuba LIM proteins: Ajuba, LIMD1, WTIP) are cytosolic adapter proteins recruited to nascent epithelial adherens junctions, where they are thought to contribute to junctional assembly and/or stability. They also shuttle into the nucleus acting as corepressors of the Snail family of transcriptional repressors, thereby contributing to epithelial mesenchymal transition. As such they have the potential to communicate cell adhesive events with nuclear responses to remodel epithelia. Determining their role(s) in vivo, however, has been challenging due to shared interacting proteins, overlapping tissue expression and functional redundancy in cells. Thus, we turned to the Drosophila model system where a …

Characterization Of Streptolysin O As The Translocator For The Cytolysin-Mediated Translocation Process In Streptococcus Pyogenes, N'Goundo Magassa

All Theses and Dissertations (ETDs)

Secretion of toxins into host cells is an important component of microbial pathogenesis. In order to gain access to the host cell cytosol, toxins must cross the plasma membrane, traverse the membrane of endocytic vesicles, or cross the membrane of organelles. The process cytolysin-mediated translocation: CMT) in Streptococcus pyogenes uses the pore-forming protein streptolysin O: SLO) to translocate the S. pyogenes NAD+-glycohydrolase: SPN) effector into the cytosol of eukaryotic host cells. Although, the fundamentals of this protein translocation process are established the details of the mechanism remain elusive. The current studies illustrate that the translocation process is more complex than …

Mechanisms Of Copper Deficiency In The Zebrafish Embryo, Erik Madsen

All Theses and Dissertations (ETDs)

Proper maternal nutrition is critical for early embryonic development. Despite overwhelming epidemiologic data indicating the benefits nutrient supplementation for the developing organism we do not fully understand the genetics of predisposition to abnormal developmental phenotypes when faced with suboptimal nutrient levels. Copper is an essential nutrient required for critical biochemical processes. Severe defects in copper homeostasis lead to significant disease typified by the X-linked recessive disorder Menkes disease. Patients with Menkes disease have cutis laxa, bone deformities, hypopigmentation, arterial malformation, and neurodegeneration due to copper deficiency caused by loss-of-function mutations in ATP7A, a copper transport protein. Despite the critical requirement …

Functional Genomic Examinations Of Interactions Between Common Members Of The Human Gut Microbiota, Michael Mahowald

All Theses and Dissertations (ETDs)

The adult human gut microbiota consists of hundreds to thousands of bacterial species, the majority belonging to the Bacteroidetes and the Firmicutes. Differences in the balance between these phyla has been linked to obesity in mice and humans. However, little is known about their interactions in vivo. I have used comparative and functional genomics, proteomics and biochemical assays to identify the ways they marshal their genomic resources to adapt to life together in the distal gut. I first annotated the complete genome sequences of two human gut Bacteroidetes (Bacteroides vulgatus and Parabacteroides distasonis) and two Firmicutes (Eubacterium rectale and E. …

Age And Age Structure Of An Invasive Plant, Lythrum Salicaria, Kimberly L. Therrien

Master's Theses and Capstones

My objective was to determine whether purple loosestrife (Lythrum salicaria L.) individuals could be aged using the pattern of ramet production. Assuming current year loosestrife ramets produce new basal ramets only in the following year, plant age could be estimated by counting ranks of sequentially produced ramets. I found that in four New Hampshire wetlands the assumptions of the method were generally met, although some ramets were not produced sequentially. Using ramet counts I was able to estimate minimum age for individuals in each of the four populations. All populations were dominated by individuals > 1 year old. I tested whether …

Isotopic Analysis Of Arctic Ground Squirrel Tissues And Potential Food Sources, Julee Shamhart

Master's Theses and Capstones

Given limited knowledge of the food sources of Arctic ground squirrels, an important arctic prey species, it is difficult to predict the implications of changes in food source availability that could result from climate change. I hypothesized that Arctic ground squirrels at two colonies, Atigun and Toolik, would have similar feeding habits and mushrooms would contribute to their diet The Arctic ground squirrels at Toolik had significantly higher del15N (3.7 per mill difference) and del13C values (1.3 per mill difference) than those at Atigun. Mixing models indicated that the signatures observed in the Atigun hair could result from a combination …

Bryostatins: Biological Context And Biotechnological Prospects, Amaro E. Trindade-Silva, Grace E. Lim-Fong, Koty H. Sharp

Arts & Sciences Faculty Publications

Coral animals harbor diverse microorganisms in their tissues, including archaea, bacteria, viruses, and Bryostatins are a family of protein kinase C modulators that have potential applications in biomedicine. Found in miniscule quantities in a small marine invertebrate, lack of supply has hampered their development. In recent years, bryostatins have been shown to have potent bioactivity in the central nervous system, an uncultivated marine bacterial symbiont has been shown to be the likely natural source of the bryostatins, the bryostatin biosynthetic genes have been identified and characterized, and bryostatin analogues with promising biological activity have been developed and tested. Challenges in …

Seeing The Future: Biology Research Allows Undergraduates New Insight Into Their Own Futures, Merideth Krevosky, Jeffery Bowen

Bridgewater Review

No abstract provided.

Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora

Theses and Dissertations - UTB/UTPA

Nerodia rhombifer is a polytypic, semi-aquatic snake with a broad geographical distribution ranging from the American Midwest southward to Chiapas, Mexico. Although relatively abundant throughout much of its range, few ecological studies of the species have been conducted. This study provides basic population ecology information in a subtropical habitat. Population data were obtained in a mark-recapture study at Santa Ana National Wildlife Refuge, Hidalgo County, Texas, from August 1995 to December 1998. Specimens taken elsewhere in Hidalgo County provided information on the reproductive biology. This study provides the first absolute density estimates from anywhere within the species’ range. Quantitative information …

Minnesota Tuning Project: Biology And Graphic Design, Kristi L. Kremers, Krista M. Soria, Lynn D. Akey

Academic Affairs Publications

Within the tuning methodology, a key step is the utilization of a consultative survey. The objectives established in the Bologna process for the tuning survey “include gleaning current perspectives on the diversity of practice and commonality of knowledge across borders and traditions, and seeking a simple and accessible language to create a scaffolding on which the various degrees can work in comfort and trust” (Adelman, 2009, p. 49). The Minnesota tuning surveys sought the consultation of previous graduates, current students, employers of graduates, and academic faculty for each of the disciplines involved in tuning.

An Intertidal Sea Star Adjusts Thermal Inertia To Avoid Extreme Body Temperatures, Sylvain Pincebourde, Eric Sanford, Brian Helmuth

Faculty Publications

The body temperature of ectotherms is influenced by the interaction of abiotic conditions, morphology, and behavior. Although organisms living in different thermal habitats may exhibit morphological plasticity or move from unfavorable locations, there are few examples of animals adjusting their thermal properties in response to short-term changes in local conditions. Here, we show that the intertidal sea star Pisaster ochraceus modulates its thermal inertia in response to prior thermal exposure. After exposure to high body temperature at low tide, sea stars increase the amount of colder than-air fluid in their coelomic cavity when submerged during high tide, resulting in a …

Lifelines Fall 2009, Southern Adventist University

Lifelines - Biology Department Newsletter

The Fall 2009 issue of Lifelines includes articles on Southern's Ancient DNA Project, an alumni feature, student research, and news from the Pre-Dent Club.

The Influences Of Cell Type And Zno Nanoparticle Size On Immune Cell Cytotoxicity And Cytokine Induction, Cory Hanley, Aaron Thurber, Charles Hanna, Alex Punnoose, Jianhui Zhang, Denise G. Wingett

Physics Faculty Publications and Presentations

Nanotechnology represents a new and enabling platform that promises to provide a range of innovative technologies for biological applications. ZnO nanoparticles of controlled size were synthesized, and their cytotoxicity towards different human immune cells evaluated. A differential cytotoxic response between human immune cell subsets was observed, with lymphocytes being the most resistant and monocytes being the most susceptible to ZnO nanoparticle-induced toxicity. Significant differences were also observed between previously activated memory lymphocytes and naive lymphocytes, indicating a relationship between cell-cycle potential and nanoparticle susceptibility. Mechanisms of toxicity involve the generation of reactive oxygen species, with monocytes displaying the highest levels, …

Integrated Genomics Of Susceptiblity To Therapy-Related Leukemia, Patrick Cahan

All Theses and Dissertations (ETDs)

Therapy-related acute myeloid leukemia t-AML is a secondary, generally incurable, malignancy attributable to the chemotherapeutic treatment of an initial disease. Although there is a genetic component to susceptibility to therapy-related leukemias in mice, little is understood either about the contributing loci, or the mechanisms by which susceptibility factors mediate their effect. An improved understanding of susceptibility factors and the biological processes in which they act may lead to the development of t-AML prevention strategies. In this thesis work, we identified expression networks that are associated with t-AML susceptibility in mice. These networks are robust in that they emerge from distinct …

Genomic Approaches For Pathway Identification In Regenerating Sensory Epithelia Of The Inner Ear, David Alvarado

All Theses and Dissertations (ETDs)

The inner ear utilizes sensory hair cells as mechano-electric transducers for sensing sound and balance. In mammals, these sensory hair cells lack the capacity for regeneration and if damaged lead to hearing or balance disorders. However, non-mammalian vertebrates such as birds maintain their regenerative abilities throughout their life. We completed a gene expression profiling time course of regenerating sensory epithelia: SE) in avian cochlea and utricle on a custom transcription factor microarray following damage by laser and chemical ablation and identified genes from known signaling cascades differentially expressed during SE regeneration. In the second study, we selected 27 of these …

Growth Factor Delivery From Fibrin Matrics Containing Affinity-Based Delivery Systems To Treat Peripheral Nerve Injury, Matthew Wood

All Theses and Dissertations (ETDs)

This thesis work sought to develop a biomaterial to further the understanding of affinity-based delivery and to serve as a potential treatment for peripheral nerve injury. The use of an affinity-based delivery system: ABDS) with growth factors in a nerve guidance conduit: NGC) was hypothesized to promote nerve regeneration and functional recovery following a critical nerve defect. Evaluation of affinity-based delivery using peptides with varying binding affinity for heparin determined that peptide binding affinity for heparin affected the release rate and biological activity of nerve growth factor: NGF) in vitro. The ABDS presented biologically active NGF, which promoted neurite extension …

Uropathogenic E. Coli Employ A Conserved Intracellular Infection Pathway That Can Be Inhibited By Novel Anti-Virulence Therapeutics, Corinne Cusumano

All Theses and Dissertations (ETDs)

Urinary tract infections: UTIs) affect 13 million women annually in the United States and are predominately caused by uropathogenic Escherichia coli: UPEC). In a murine cystitis model, UPEC utilize a multistep pathogenic pathway in which they invade and form intracellular bacterial communities: IBCs) within bladder facet cells. Type 1 pili expressing the adhesin, FimH, are necessary for UPEC binding and invasion of urothelial cells and formation of IBCs. UPEC ultimately disperse from the IBC, many with filamentous morphology, and infect other host urothelial cells. Using a panel of UPEC clinical isolates, this work evaluates the conservation of the IBC pathway …