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Relationship Between Serum And Brain Carotenoids, 𝛼-Tocopherol, And Retinol Concentrations And Cognitive Performance In The Oldest Old From The Georgia Centenarian Study, Elizabeth J. Johnson, Rohini Vishwanathan, Mary Ann Johnson, Dorothy B. Hausman, Adam Davey, Tammy M. Scott, Robert C. Green, L. Stephen Miller, Marla Gearing, John Woodard, Peter T. Nelson, Hae-Yun Chung, Wolfgang Schalch, Jonas Wittwer, Leonard W. Poon Jan 2013

Relationship Between Serum And Brain Carotenoids, 𝛼-Tocopherol, And Retinol Concentrations And Cognitive Performance In The Oldest Old From The Georgia Centenarian Study, Elizabeth J. Johnson, Rohini Vishwanathan, Mary Ann Johnson, Dorothy B. Hausman, Adam Davey, Tammy M. Scott, Robert C. Green, L. Stephen Miller, Marla Gearing, John Woodard, Peter T. Nelson, Hae-Yun Chung, Wolfgang Schalch, Jonas Wittwer, Leonard W. Poon

Department of Nutrition and Health Sciences: Faculty Publications

Oxidative stress is involved in age-related cognitive decline. The dietary antioxidants, carotenoids, tocopherols, and vitamin A may play a role in the prevention or delay in cognitive decline. In this study, sera were obtained from 78 octogenarians and 220 centenarians from the Georgia Centenarian Study. Brain tissues were obtained from 47 centenarian decedents. Samples were analyzed for carotenoids, 𝛼-tocopherol, and retinol using HPLC. Analyte concentrations were compared with cognitive tests designed to evaluate global cognition, dementia, depression and cognitive domains (memory, processing speed, attention, and executive functioning). Serum lutein, zeaxanthin, and 𝛽-carotene concentrations were most consistently related to better cognition …


Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori Jan 2013

Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori

Biological Sciences Faculty Publications

Species that sequester toxins from prey for their own defense against predators may exhibit population-level variation in their chemical arsenal that reflects the availability of chemically defended prey in their habitat. Rhabdophis tigrinus is an Asian snake that possesses defensive glands in the skin of its neck (nuchal glands'), which typically contain toxic bufadienolide steroids that the snakes sequester from consumed toads. In this study, we compared the chemistry of the nuchal gland fluid of R.tigrinus from toad-rich and toad-free islands in Japan and determined the effect of diet on the nuchal gland constituents. Our findings demonstrate that captive-hatched juveniles …


An Investigation Of Alternative Oxidase Presence, Expression, And Regulation In The Moss Physcomitrella Patens, Karina I. Neimanis Jan 2013

An Investigation Of Alternative Oxidase Presence, Expression, And Regulation In The Moss Physcomitrella Patens, Karina I. Neimanis

Theses and Dissertations (Comprehensive)

Alternative oxidase (AOX) is an inner mitochondrial membrane protein that introduces a branch point at ubiquinone within the respiratory electron transport system (ETS). The AOX protein bypasses two sites of proton translocation within the ETS and as a result the yield of ATP per oxygen consumed is significantly reduced. Although AOX appears to be energetically wasteful, recent studies have revealed that AOX has a wide taxonomic distribution. AOX multigene families, transcripts, protein levels, and enzymatic activity have been most thoroughly characterized in many angiosperm (flowering) plants. Given the data available for angiosperm AOXs, evidence of non-angiosperm AOXs in the primary …


Wildlife In Airport Environments: Chapter 13 Radar Technology To Monitor Hazardous Birds At Airports, Sidney A. Gauthreaux Jr., Paige M. Schmidt Jan 2013

Wildlife In Airport Environments: Chapter 13 Radar Technology To Monitor Hazardous Birds At Airports, Sidney A. Gauthreaux Jr., Paige M. Schmidt

United States Department of Agriculture Wildlife Services: Staff Publications

Bird strikes are the most common wildlife hazard to aviation safety (Dolbeer et ale 2000). Advances in habitat management at airports through the elimination and reduction of attractants, in combination with hazing and lethal control, have reduced avian hazards < 152 m (500 feet) above ground level. Bird strikes above this altitude, however, are beyond the limits of traditional wildlife control techniques (Dolbeer 2011). Traditional avian survey methods used to monitor birds at airports (Cleary and Dolbeer 2005; Chapter 14) often fail to provide essential information on local bird activity and migration at higher altitudes, hazardous bird use of attractants near airports, and bird activity at night-information that could be provided by the strategic use of radar technology at and near airports (Dolbeer 2006).


Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano Jan 2013

Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano

Open Access Theses & Dissertations

Glucocorticoids are a class of steroid hormones that can either be produced synthetically or naturally by the adrenal glands. The synthetic glucocorticoids are highly prescribed in the United States for their anti-inflammatory and immunosuppressive properties to treat a variety of ailments and diseases; however, these have been implicated in a number of adverse human conditions such as obesity, metabolic syndrome, immune-suppression, delayed puberty, adrenal insufficiency and Cushing Syndrome, among others. Ongoing research has shown that synthetic and natural hormones are transported to aquatic environments via mammalian excretion or wastewater effluent, and as a result, the release of glucocorticoids into the …


Ecology And Invasive Properties Of Musk Thistle (Carduus Nutans) In The Central Prairies Of Nebraska, Chengchou Han Dec 2012

Ecology And Invasive Properties Of Musk Thistle (Carduus Nutans) In The Central Prairies Of Nebraska, Chengchou Han

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Musk thistle (Carduus nutans) is an herbaceous monocarpic herb introduced to the U. S. from Eurasia. The invasion of musk thistle can reduce forage area, soil stability, and reduce recreation and open areas for humans and wildlife.

Resistance of warm season and cool season perennial grass communities to musk thistle invasion is important for land managers to consider, especially where disturbance has made an area particularly susceptible. Our results show that disturbances, such as overgrazing can open up niches in canopies of warm season grass communities and facilitate invasion but not in cool season grass communities. The mechanism …


Sinusoidal Endothelial Dysfunction In Non-Alcoholic Fatty Liver Disease., Sandhya Lakshmi Gopalakrishnan Nov 2012

Sinusoidal Endothelial Dysfunction In Non-Alcoholic Fatty Liver Disease., Sandhya Lakshmi Gopalakrishnan

Department of Biochemistry: Dissertations, Theses, and Student Research

Non-alcoholic fatty liver disease (NAFLD) is an asymptomatic increasingly common disorder that affects liver metabolism and is often the precursor for liver pathologies such as fibrosis, cirrhosis and hepato-cellular carcinoma. The liver sinusoidal endothelial cells act as a liver sieve by allowing macromolecules and chylomicrons to traverse through their fenestrations (sieve plates) to hepatocytes. Since liver sinusoidal endothelial cells (LSEC) regulate serum derived macromolecular exposure to hepatocytes, we asked what role LSEC could play in the pathogenesis of NAFLD. To investigate the early events of NAFLD we used a rat model (Sprague-Dawley) in which animals were maintained on standard and …


Cephalopod Genomics: A Plan Of Strategies And Organization, Caroline B. Albertin, Laure Bonnaud, C. Titus Brown, Wendy J. Crookes-Goodson, Rute R. Da Fonseca, Carlo Di Cristo, Brian P. Dilkes, Eric Edsinger-Gonzales, Robert M. Freeman Jr., Roger T. Hanlon, Kristen M. Koenig, Annie R. Lindgren, Mark Q. Martindale, Patrick Minx, Leonid L. Moroz, Marie-Therese Nödl, Spencer V. Nyholm, Atsushi Ogura, Judit R. Pungor, Joshua J. C. Rosenthal, Erich M. Schwarz, Shuichi Shigeno, Jan M. Strugnell, Tim Wollesen, Guojie Zhang, Clifton W. Ragsdale Oct 2012

Cephalopod Genomics: A Plan Of Strategies And Organization, Caroline B. Albertin, Laure Bonnaud, C. Titus Brown, Wendy J. Crookes-Goodson, Rute R. Da Fonseca, Carlo Di Cristo, Brian P. Dilkes, Eric Edsinger-Gonzales, Robert M. Freeman Jr., Roger T. Hanlon, Kristen M. Koenig, Annie R. Lindgren, Mark Q. Martindale, Patrick Minx, Leonid L. Moroz, Marie-Therese Nödl, Spencer V. Nyholm, Atsushi Ogura, Judit R. Pungor, Joshua J. C. Rosenthal, Erich M. Schwarz, Shuichi Shigeno, Jan M. Strugnell, Tim Wollesen, Guojie Zhang, Clifton W. Ragsdale

Biology Faculty Publications and Presentations

The Cephalopod Sequencing Consortium (CephSeq Consortium) was established at a NESCent Catalysis Group Meeting, “Paths to Cephalopod Genomics- Strategies, Choices, Organization,” held in Durham, North Carolina, USA on May 24-27, 2012. Twenty-eight participants representing nine countries (Austria, Australia, China, Denmark, France, Italy, Japan, Spain and the USA) met to address the pressing need for genome sequencing of cephalopod mollusks. This group, drawn from cephalopod biologists, neuroscientists, developmental and evolutionary biologists, materials scientists, bioinformaticians and researchers active in sequencing, assembling and annotating genomes, agreed on a set of cephalopod species of particular importance for initial sequencing and developed strategies and an …


Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott Oct 2012

Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott

Biological Sciences Theses & Dissertations

Little is known about the life history and overall ecology of bottlenose dolphins that strand in Virginia. In this study, I examined archived life history samples and stranding data from bottlenose dolphins found in Virginia waters to (1) develop growth curves based on ages from sectioned teeth, (2) document characteristics of male and female reproductive organs, and (3) define the relationship between age/length and presence of neonatal characteristics during the first year of life. The Gompertz growth model provided the best fit of growth data for stranded T. truncatus in Virginia. Length at birth and asymptotic length for males were …


Characterization Of The Stem Cell Niche In Drosophila Testes, Vittorio Mena Jr. Oct 2012

Characterization Of The Stem Cell Niche In Drosophila Testes, Vittorio Mena Jr.

Seton Hall University Dissertations and Theses (ETDs)

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Arabidopsis Bhlh100 And Bhlh101 Control Iron Homeostasis Via A Fit-Independent Pathway, Alicia B. Sivitz, Victor Hermand, Catherine Curie, Grégory Vert Sep 2012

Arabidopsis Bhlh100 And Bhlh101 Control Iron Homeostasis Via A Fit-Independent Pathway, Alicia B. Sivitz, Victor Hermand, Catherine Curie, Grégory Vert

Dartmouth Scholarship

Iron deficiency induces a complex set of responses in plants, including developmental and physiological changes, to increase iron uptake from soil. In Arabidopsis, many transporters involved in the absorption and distribution of iron have been identified over the past decade. However, little is known about the signaling pathways and networks driving the various responses to low iron. Only the basic helix–loop–helix (bHLH) transcription factor FIT has been shown to control the expression of the root iron uptake machinery genes FRO2 and IRT1. Here, we characterize the biological role of two other iron-regulated transcription factors, bHLH100 and bHLH101, in iron homeostasis. …


Antony Van Leeuwenhoek: Creation “Magnified” Through His Magnificent Microscopes, Alan L. Gillen, Douglas Oliver Aug 2012

Antony Van Leeuwenhoek: Creation “Magnified” Through His Magnificent Microscopes, Alan L. Gillen, Douglas Oliver

Faculty Publications and Presentations

Although van Leeuwenhoek was not the inventor of the microscope, he advanced it more than anyone else for seeing living things.

Antony van Leeuwenhoek1 (Fig. 1) found great joy in God’s smallest creatures. He first discovered protozoans in his youth. The Dutch haberdasher retained a child-like joy of discovery from his youth until his death at age 90. He lived to see tiny microbes though his homemade microscopes. He loved to grind and focus a new lens in order to see the unseen world. Leeuwenhoek spent countless hours grinding tiny lenses and looking through them. This Christian lay biologist …


Methylene Blue Modulates Huntingtin Aggregation Intermediates And Is Protective In Huntington's Disease Models, Emily M. Sontag, Gregor P. Lotz, Namita Agrawal, Andrew Tran, Rebecca Aron, Guocheng Yang, Mihaela Necula, Alice Lau, Steven Finkbeiner, Charles G. Glabe, J. Lawrence Marsh, Paul J. Muchowski, Leslie M. Thompson Aug 2012

Methylene Blue Modulates Huntingtin Aggregation Intermediates And Is Protective In Huntington's Disease Models, Emily M. Sontag, Gregor P. Lotz, Namita Agrawal, Andrew Tran, Rebecca Aron, Guocheng Yang, Mihaela Necula, Alice Lau, Steven Finkbeiner, Charles G. Glabe, J. Lawrence Marsh, Paul J. Muchowski, Leslie M. Thompson

Biological Sciences Faculty Research and Publications

Huntington's disease (HD) is a devastating neurodegenerative disorder with no disease-modifying treatments available. The disease is caused by expansion of a CAG trinucleotide repeat and manifests with progressive motor abnormalities, psychiatric symptoms, and cognitive decline. Expression of an expanded polyglutamine repeat within the Huntingtin (Htt) protein impacts numerous cellular processes, including protein folding and clearance. A hallmark of the disease is the progressive formation of inclusions that represent the culmination of a complex aggregation process. Methylene blue (MB), has been shown to modulate aggregation of amyloidogenic disease proteins. We investigated whether MB could impact mutant Htt-mediated aggregation and neurotoxicity. MB …


Greater Galagos Near Mt. Kasigau, Kenya: Population Density Estimates, Andrea Falcetto Aug 2012

Greater Galagos Near Mt. Kasigau, Kenya: Population Density Estimates, Andrea Falcetto

Masters Theses & Specialist Projects

This study examined population density and habitat use of a species of greater galago, genus Otolemur, around Mt. Kasigau, Kenya. Mt. Kasigau has a unique regional microclimate, a cloud forest, which provides many different flora and fauna a home. To examine population density, two different methods were used. The first method was using line transects and analyzing results using Distance 6.0. These surveys were conducted during both dry and wet season and results were compared after the study. The second method was to trap individuals and use mark-recapture to determine population density. When caught in a trap, individuals were …


Trapping And Control Of The Small Hive Beetle, Aethina Tumida, An Invasive Parasite Of Honey Bees, Apis Mellifera, Shannon Peterson Aug 2012

Trapping And Control Of The Small Hive Beetle, Aethina Tumida, An Invasive Parasite Of Honey Bees, Apis Mellifera, Shannon Peterson

All Theses

The small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae), is one of the most recent honey bee pests of economic importance, especially in the southeastern United States. Various in-hive traps have been developed to attempt to control the populations of this invasive pest within honey bee colonies. The first year of my research focused on comparing the effectiveness of three commercially available traps for removing small hive beetles. Thirty-two colonies were established with 0.9-kg package bees with a queen in four apiaries. Eight colonies were placed in each apiary, each colony randomly receiving one of four treatments: the three-chambered Hood …


Gene Ontology Analysis Of Pairwise Genetic Associations In Two Genome-Wide Studies Of Sporadic Als, Nora Chung Kim, Peter C. Andrews, Folkert W. Asselbergs, H Robert Frost, Scott M. Williams, Brent T. Harris, Cynthia Read, Kathleen D. Askland, Jason H. Moore Jul 2012

Gene Ontology Analysis Of Pairwise Genetic Associations In Two Genome-Wide Studies Of Sporadic Als, Nora Chung Kim, Peter C. Andrews, Folkert W. Asselbergs, H Robert Frost, Scott M. Williams, Brent T. Harris, Cynthia Read, Kathleen D. Askland, Jason H. Moore

Dartmouth Scholarship

It is increasingly clear that common human diseases have a complex genetic architecture characterized by both additive and nonadditive genetic effects. The goal of the present study was to determine whether patterns of both additive and nonadditive genetic associations aggregate in specific functional groups as defined by the Gene Ontology (GO).


Early Stage Drug Treatment That Normalizes Proinflammatory Cytokine Production Attenuates Synaptic Dysfunction In A Mouse Model That Exhibits Age-Dependent Progression Of Alzheimer's Disease-Related Pathology, Adam D. Bachstetter, Christopher M. Norris, Pradoldej Sompol, Donna M. Wilcock, Danielle Goulding, Janna H. Neltner, Daret St. Clair, D. Martin Watterson, Linda J. Van Eldik Jul 2012

Early Stage Drug Treatment That Normalizes Proinflammatory Cytokine Production Attenuates Synaptic Dysfunction In A Mouse Model That Exhibits Age-Dependent Progression Of Alzheimer's Disease-Related Pathology, Adam D. Bachstetter, Christopher M. Norris, Pradoldej Sompol, Donna M. Wilcock, Danielle Goulding, Janna H. Neltner, Daret St. Clair, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Overproduction of proinflammatory cytokines in the CNS has been implicated as a key contributor to pathophysiology progression in Alzheimer's disease (AD), and extensive studies with animal models have shown that selective suppression of excessive glial proinflammatory cytokines can improve neurologic outcomes. The prior art, therefore, raises the logical postulation that intervention with drugs targeting dysregulated glial proinflammatory cytokine production might be effective disease-modifying therapeutics if used in the appropriate biological time window. To test the hypothesis that early stage intervention with such drugs might be therapeutically beneficial, we examined the impact of intervention with MW01-2-151SRM (MW-151), an experimental therapeutic that …


Evaluating The Performance Of Computational Approaches For Identifying Critical Sites In Protein-Coding Dna Sequences, Matthew Lewis Bendall Jul 2012

Evaluating The Performance Of Computational Approaches For Identifying Critical Sites In Protein-Coding Dna Sequences, Matthew Lewis Bendall

Theses and Dissertations

The ability to link a particular phenotype to its causative genotype is one of the most challenging objectives for biological research. Although the genetic code provides an explicit formula for determining the sequence of amino acid phenotypes produced by a given nucleotide sequence, identifying specific residues that are functionally important remains problematic. Many computational approaches have been developed that use patterns observed in DNA sequences to identify these critical sites. However, very few research studies have used empirical data to test whether these approaches are truly able to identify sites of interest.In most empirical studies, the actual protein function and …


The Proteomics Of Lipid Droplets: Structure, Dynamics, And Functions Of The Organelle Conserved From Bacteria To Humans., Li Yang, Yunfeng Ding, Yong Chen, Shuyan Zhang, Chaoxing Huo, Yang Wang, Jinhai Yu, Peng Zhang, Huimin Na, Huina Zhang, Yanbin Ma, Pingsheng Liu Jul 2012

The Proteomics Of Lipid Droplets: Structure, Dynamics, And Functions Of The Organelle Conserved From Bacteria To Humans., Li Yang, Yunfeng Ding, Yong Chen, Shuyan Zhang, Chaoxing Huo, Yang Wang, Jinhai Yu, Peng Zhang, Huimin Na, Huina Zhang, Yanbin Ma, Pingsheng Liu

College of Science & Mathematics Departmental Research

Lipid droplets are cellular organelles that consists of a neutral lipid core covered by a monolayer of phospholipids and many proteins. They are thought to function in the storage, transport, and metabolism of lipids, in signaling, and as a specialized microenvironment for metabolism in most types of cells from prokaryotic to eukaryotic organisms. Lipid droplets have received a lot of attention in the last 10 years as they are linked to the progression of many metabolic diseases and hold great potential for the development of neutral lipid-derived products, such as biofuels, food supplements, hormones, and medicines. Proteomic analysis of lipid …


Nuclear Migration And Spermatid Elongation During Spermiogenesis In Drosophila Pseudoobscura, Benjamin S. Reimer Jul 2012

Nuclear Migration And Spermatid Elongation During Spermiogenesis In Drosophila Pseudoobscura, Benjamin S. Reimer

Theses

No abstract provided.


Impacts Of Upstream Drought And Water Withdrawals On The Health And Survival Of Downstream Estuarine Oyster Populations, Laura E. Petes, Alicia J. Brown, Carley R. Knight Jul 2012

Impacts Of Upstream Drought And Water Withdrawals On The Health And Survival Of Downstream Estuarine Oyster Populations, Laura E. Petes, Alicia J. Brown, Carley R. Knight

Faculty Publications

Increases in the frequency, duration, and severity of regional drought pose major threats to the health and integrity of downstream ecosystems. During 2007-2008, the U.S. southeast experienced one of the most severe droughts on record. Drought and water withdrawals in the upstream watershed led to decreased freshwater input to Apalachicola Bay, Florida, an estuary that is home to a diversity of commercially and ecologically important organisms. This study applied a combination of laboratory experiments and field observations to investigate the effects of reduced freshwater input on Apalachicola oysters. Oysters suffered significant disease-related mortality under high-salinity, drought conditions, particularly during the …


Aquatic Heteroptera Of The Lake Manguao Catchment, Palawan And New Rank Of Rhagovelia Kawakamii Hoberlandti Hungerford & Matsuda 1961, Hendrik Freitag, Herbert Zettel Jun 2012

Aquatic Heteroptera Of The Lake Manguao Catchment, Palawan And New Rank Of Rhagovelia Kawakamii Hoberlandti Hungerford & Matsuda 1961, Hendrik Freitag, Herbert Zettel

Biology Faculty Publications

Results of an inventory of the fauna of aquatic and semiaquatic true bugs (Insecta: Hemiptera) of small streams in a lake catchment of northern Palawan are presented. Twenty-one species were recorded. Taxonomic and ecological notes, distribution and collection sites are given for each identified taxon. Rhagovelia hoberlandti Hungerford & Matsuda 1961 is newly ranked as a subspecies of R. kawakamii (Matsumura 1913): Rhagovelia kawakamii hoberlandti Hungerford & Matsuda 1961, stat.n. Cercotmetus asiaticus Amyot & Serville 1843 is recorded for the first time from the Philippines. Endemic and few undescribed taxa are discussed. Additional environmental data of the sampled waters are …


Challenges For Biological Interpretation Of Environmental Proteomics Data In Non-Model Organisms, Wesley W. Dowd Jun 2012

Challenges For Biological Interpretation Of Environmental Proteomics Data In Non-Model Organisms, Wesley W. Dowd

Biology Faculty Works

Environmental physiology, toxicology, and ecology and evolution stand to benefit substantially from the relatively recent surge of “omics” technologies into these fields. These approaches, and proteomics in particular, promise to elucidate novel and integrative functional responses of organisms to diverse environmental challenges, over a variety of time scales and at different levels of organization. However, application of proteomics to environmental questions suffers from several challenges—some unique to high-throughput technologies and some relevant to many related fields—that may confound downstream biological interpretation of the data. I explore three of these challenges in environmental proteomics, emphasizing the dependence of biological conclusions on …


Spiders Of Riparian Communities In The Cockscomb Basin Wildlife Sanctuary, Belize, Megan Chevis May 2012

Spiders Of Riparian Communities In The Cockscomb Basin Wildlife Sanctuary, Belize, Megan Chevis

Honors Theses

Currently there is little literature on what arachnids inhabit the tropics of Central America, especially within the country of Belize. This study aimed to find which spider species are found in riparian areas within the Cockscomb Basin Wildlife Sanctuary in central Belize and to distinguish trends among spiders and the microhabitats in which they live. Nocturnal samples were predicted to have greater diversity than diurnal samples at all sites. Pisauridae, Salticidae, and Lycosidae were predicted to be the most common spider families collected. Specimens were collected from three riparian sites located on trails within Cockscomb. Diurnal and nocturnal samples were …


The Role Of Actin Binding Proteins In Cell Motility, Elizabeth Ojukwu May 2012

The Role Of Actin Binding Proteins In Cell Motility, Elizabeth Ojukwu

Honors Scholar Theses

Actin binding proteins (ABPs) play key roles in the dynamic organization of the actin cytoskeleton during cell movement. The general localization of ABPs during dynamic cellular processes has been characterized. However, their specific functions and mechanisms of regulating the cytoskeleton during motile cellular processes remain unclear. Two approaches have been utilized to ask how these proteins contribute to cytoskeletal function during motility. Using homologous recombination, mutant cell lines lacking α-actinin, fimbrin or both proteins have been created. By analyzing mutants that lack these proteins, we hope to disrupt processes that require a functional cytoskeleton such as phagocytosis, random motility, development, …


A Bayesian Approach To Pathway Analysis By Integrating Gene–Gene Functional Directions And Microarray Data, David W. Rowe, Yifang Zhao, Ming-Hui Chen, Dong-Guk Shin, Lynn Kuo May 2012

A Bayesian Approach To Pathway Analysis By Integrating Gene–Gene Functional Directions And Microarray Data, David W. Rowe, Yifang Zhao, Ming-Hui Chen, Dong-Guk Shin, Lynn Kuo

UCHC Articles - Research

Many statistical methods have been developed to screen for differentially expressed genes associated with specific phenotypes in the microarray data. However, it remains a major challenge to synthesize the observed expression patterns with abundant biological knowledge for more complete understanding of the biological functions among genes. Various methods including clustering analysis on genes, neural network, Bayesian network and pathway analysis have been developed toward this goal. In most of these procedures, the activation and inhibition relationships among genes have hardly been utilized in the modeling steps. We propose two novel Bayesian models to integrate the microarray data with the putative …


Characterization Of Novel Histone H2b Mutants Associated With Chromosome Segregation Defects In Saccharomyces Cerevisiae, Thiruchelvam Rajagopal May 2012

Characterization Of Novel Histone H2b Mutants Associated With Chromosome Segregation Defects In Saccharomyces Cerevisiae, Thiruchelvam Rajagopal

Graduate Theses and Dissertations

Histones are small basic proteins that associate with DNA to form the basic unit of chromatin, the nucleosome. Histones H3 and H4 form a tetramer that is bound by two H2A-H2B dimers to form the histone octamer, to which approximately 146 bp of DNA wrap around to form the nucleosome. High resolution structural information and recent advances in the understanding of histone post-translational modifications have illuminated the many regulatory functions chromatin exerts in the cell, from the transcriptional control of gene expression to chromosome segregation. However, the specific role that histones play in these processes is not well understood. Previous …


Determining The Genotype-Phenotype Connection In Synthetic Inducible Gene Expression Systems, Rhys M. Adams May 2012

Determining The Genotype-Phenotype Connection In Synthetic Inducible Gene Expression Systems, Rhys M. Adams

Dissertations and Theses (Open Access)

Introduction Gene expression is an important process whereby the genotype controls an individual cell’s phenotype. However, even genetically identical cells display a variety of phenotypes, which may be attributed to differences in their environment. Yet, even after controlling for these two factors, individual phenotypes still diverge due to noisy gene expression. Synthetic gene expression systems allow investigators to isolate, control, and measure the effects of noise on cell phenotypes. I used mathematical and computational methods to design, study, and predict the behavior of synthetic gene expression systems in S. cerevisiae, which were affected by noise.

Methods I created probabilistic …


Migration Distance And Sexual Dichromatism: Cost Of Migration Is Correlated With Reduced Female Coloration In Wood Warblers, Richard K. Simpson Apr 2012

Migration Distance And Sexual Dichromatism: Cost Of Migration Is Correlated With Reduced Female Coloration In Wood Warblers, Richard K. Simpson

Biology Honors Theses

Avian sexual dichromatism has been observed to be greater at higher latitudes, and one of the long-standing explanations for the underlying evolutionary forces underlying this geographic pattern is the breeding latitude hypothesis, which focuses on changes in male ornamentation and posits that sexual selection for male ornamentation is stronger at higher latitudes. I offer an alterative hypothesis that focuses on how changes in female coloration can drive the evolution of sexual dichromatism. I propose that the costs of migration, including increased predation risk and high energetic costs, negatively select against elaborate plumage coloration, and that the distance a species migrates …


Wetland Hydrodynamics And Long-Term Use Of Spring Migration Areas By Lesser Scaup In Eastern South Dakota, Sharon N. Kahara, Steven R. Chipps Apr 2012

Wetland Hydrodynamics And Long-Term Use Of Spring Migration Areas By Lesser Scaup In Eastern South Dakota, Sharon N. Kahara, Steven R. Chipps

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Lesser scaup (Aythya affinis [Eyton]) populations remain below their long-term average despite improved habitat conditions along spring migration routes and at breeding grounds. Scaup are typically associated with large, semipermanent wetlands and exhibit regional preferences along migration routes. Identifying consistently used habitats for conservation and restoration is complicated by irregular wetland availability due to the dynamic climate. We modeled long-term wetland use by lesser scaup in eastern South Dakota based on surveys conducted during below-average (1987-1989) and above-average (1993-2002) water condition years. Wetland permanence, longitude, and physiographic region were all significant determinants of use (P < 0.01). Long-term use was best described by a quadratic equation including wetland surface area variability, an index of wetland hydrodynamics that is linked to productivity, biodiversity, and value to waterfowl. Contrary to previous findings, our study shows that over the long term, lesser scaup are more than twice as likely to use permanent wetlands as they are semipermanent wetlands. The northern region of South Dakota's Prairie Coteau, which holds the highest density of hydrologically dynamic permanent wetlands, should be considered an area of conservation concern for lesser scaup. The criteria we identified may be used to identify important lesser scaup habitats in other regions of the Prairie Pothole Region.