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Living With Coyotes, Owen H. Agnew Dec 2015

Living With Coyotes, Owen H. Agnew

Capstones

Coyotes have been slowly moving into New York State from Canada since the 1930s. They reached Westchester County and the Bronx decades ago, and their numbers have been slowly rising. Sighting in Manhattan reached an all-time high last spring, and pet attacks in Westchester County have increased slightly in the last several years. But the slight increase in sightings and pet attacks in recent years has been amplified on social media in towns like Chappaqua, New York, where anxiety and fear about coyotes has pitted neighbors against neighbors.

Main character Frank Vincenti is a Long Island barber and a self-proclaimed …


Biomechanical Performances Of Networked Polyethylene Glycol Diacrylate: Effect Of Photoinitiator Concentration, Temperature, And Incubation Time, Morshed Khandaker, Albert Orock, Stefano Tarantini, Jeremiah White, Ozlem Yasar Dec 2015

Biomechanical Performances Of Networked Polyethylene Glycol Diacrylate: Effect Of Photoinitiator Concentration, Temperature, And Incubation Time, Morshed Khandaker, Albert Orock, Stefano Tarantini, Jeremiah White, Ozlem Yasar

Publications and Research

Nutrient conduit networks can be introduced within the Polyethylene Glycol Diacrylate (PEGDA) tissue construct to enable cells to survive in the scaffold. Nutrient conduit networks can be created on PEGDA by macrochannel to nanochannel fabrication techniques. Such networks can influence the mechanical and cell activities of PEGDA scaffold. There is no study conducted to evaluate the effect of nutrient conduit networks on the maximum tensile stress and cell activities of the tissue scaffold.The study aimed to explore the influence of the network architecture on the maximum tensile stress of PEGDA scaffold and compared with the nonnetworked PEGDA scaffold. Our study …


Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang Oct 2015

Two Distinct Modes Of Metal Ion Binding In The Nuclease Active Site Of A Viral Dna-Packaging Terminase: Insight Into The Two-Metal-Ion Catalytic Mechanism, Haiyan Zhao, Zihan Lin, Anna Y. Lynn, Brittany Varnado, John A. Beutler, Ryan P. Murelli, Stuart F.J. Le Grice, Liang Tang

Publications and Research

Many dsDNA viruses encode DNA-packaging terminases, each containing a nuclease domain that resolves concatemeric DNA into genome-length units. Terminase nucleases resemble the RNase H-superfamily nucleotidyltransferases in folds, and share a two-metal-ion catalytic mechanism. Here we show that residue K428 of a bacteriophage terminase gp2 nuclease domain mediates binding of the metal cofactor Mg2+. A K428A mutation allows visualization, at high resolution, of a metal ion binding mode with a coupled-octahedral configuration at the active site, exhibiting an unusually short metal-metal distance of 2.42 A° . Such proximity of the two metal ions may play an essential role in catalysis by …


Musical Regularity And Rhythmic Patterns: A Quantitative Analysis Of Birdsong Structure, Eathan Ezra Janney Sep 2015

Musical Regularity And Rhythmic Patterns: A Quantitative Analysis Of Birdsong Structure, Eathan Ezra Janney

Dissertations, Theses, and Capstone Projects

Birdsong is a complex, learned behavior that, like music, has meaningful units at multiple timescales. Birds perform by constructing extended presentations of their phrase repertoire. Each bird's repertoire is built from small units, such as syllables, or groups of syllables with characteristic pitch, rhythm, and timbre. Like a musician each bird has its unique structure of performance that communicates its individual identity. Also contained within a bird's performance, is information about its group identity and species identity. Like a musician's performance, a bird's singing affects the behavioral state of listeners'birds perform to attract mates and defend territory.

Subjectively, many can …


Population Genomics Of White-Footed Mice (Peromyscus Leucopus) In New York City, Stephen Edward Harris Sep 2015

Population Genomics Of White-Footed Mice (Peromyscus Leucopus) In New York City, Stephen Edward Harris

Dissertations, Theses, and Capstone Projects

Urbanization significantly alters natural ecosystems. New York City (NYC) is one of the oldest and most urbanized cities in North America, but still maintains substantial populations of some native wildlife. The white-footed mouse, Peromyscus leucopus, is a common resident of NYC's forest fragments, and isolated populations may adapt in response to novel urban ecosystems. Using pooled transcriptome-wide RNAseq data, individually barcoded transcriptome-wide RNAseq data, and genome-wide RADseq data, I found genetic differentiation between urban and rural P. leucopus populations and evidence suggestive of local adaptation. I compared genome and transcriptome-wide SNP data in P. leucopus from relatively large urban …


Cultural Evolution In Natural Populations: A Quantitative Bioacoustic Analysis, Chenghui Ju Sep 2015

Cultural Evolution In Natural Populations: A Quantitative Bioacoustic Analysis, Chenghui Ju

Dissertations, Theses, and Capstone Projects

Bird song is a powerful model system in behavioral biology, especially for learning and cultural evolution. Understanding the origins and maintenance of vocal diversity in nature is fundamentally important to acoustic biology. Here, we propose a large-scale, integrative population analysis of nearly 2000 songs of the house finch (Haemorhous mexicanus) (190 individuals) collected in western Long Island of New York during an interval of 37 years (between 1975 and 2012) to explore cultural change of bird songs. Generally, I have three aims in this study. In the chapter 1, to facilitate acoustic analysis for field recordings with ambient noise, of …


The Ecology Of Winter Flounder From An Otolith Perspective, George William Jackman Sep 2015

The Ecology Of Winter Flounder From An Otolith Perspective, George William Jackman

Dissertations, Theses, and Capstone Projects

In this dissertation, sagittal otoliths were used as a lens to examine latent life history patterns in winter flounder (Pseudopleuronectes americanus) and also as a means of interpreting the species' relationship to their abiotic and biotic environment. Otoliths provide a unique and powerful perspective into the lives of the telost fishes, because they permanently record the spatial and temporal histories through sequential growth patterns from conception to capture. The patterns of growth and dormancy in the otolith are regulated by endogenous and exogenous rhythms, and as the otolith grows, trace elements are absorbed from the ambient environment and …


Systematics And Evolution Of The Ronnbergia Alliance (Bromeliaceae): History Of Disjunct Diversification In Three Biodiversity Hotspots Of The Neotropics, Julian Andres Aguirre Santoro Sep 2015

Systematics And Evolution Of The Ronnbergia Alliance (Bromeliaceae): History Of Disjunct Diversification In Three Biodiversity Hotspots Of The Neotropics, Julian Andres Aguirre Santoro

Dissertations, Theses, and Capstone Projects

The systematics, biogeography and evolution of the 'Ronnbergia Alliance,' a nested lineage within the Core Bromelioideae, were investigated. In the first chapter, the phylogenetic relationships of the Ronnbergia Alliance were reconstructed using three chloroplast and three nuclear DNA sequence markers in combination with a wide species sampling across the Core Bromelioideae and a nearly complete species-level sampling of the five species complexes that likely comprise the Ronnbergia Alliance. The analysis indicates that the Ronnbergia Alliance is a robust monophyletic group sister to the remaining Core Bromelioideae, and it is composed by species of the polyphyletic genera Aechmea, Hohenbergia and Ronnbergia. …


Pseudomonas Bacteriophage Phi6 As A Model For Virus Emergence, Brian Elwood Ford Sep 2015

Pseudomonas Bacteriophage Phi6 As A Model For Virus Emergence, Brian Elwood Ford

Dissertations, Theses, and Capstone Projects

The Pseudomonas bacteriophage Φ6 has a long and well-established history as a model organism. Here we describe a set of experiments to extend this model system to concepts previously unclaimed. Chapter 1 presents a brief background of the ecology of viruses that infect microorganisms. Chapter 2 examines genetic mutations allowing for host range expansion. Chapter 3 presents a novel paired strain assay to study how a non genetic host-acquired factor affects fitness of these enveloped viruses on subsequent hosts. Chapter 4 is an extension of this system to include how the bacteria host is affected in virus-host coevolution.


Incipient Speciation In Freshwater Fish Species From Two Isolated Watersheds, Paula Gore Miller Sep 2015

Incipient Speciation In Freshwater Fish Species From Two Isolated Watersheds, Paula Gore Miller

Dissertations, Theses, and Capstone Projects

The process of speciation occurs as a result of restricted gene flow between segments of an interbreeding population occupying different geographic areas. This separation may result in isolated populations which undergo genetic and phenotypic changes. The Wisconsin glacial period, which ended approximately 17,500 years ago, dramatically altered the geography of North America. The glacier covered almost the entire North America as it advanced. Areas that were not covered with ice provided suitable habitats (refugia) for relict species that were previously widespread in the northern section of the continent. As the ice sheet retreated, animals and plants were able to return …


Mechanisms Of Vocal Coordination In Zebra Finches, Jonathan I. Benichov Sep 2015

Mechanisms Of Vocal Coordination In Zebra Finches, Jonathan I. Benichov

Dissertations, Theses, and Capstone Projects

Social animals frequently emit communication calls. Although these calls are often innate in their acoustic structure, they can be used adaptably to coordinate behavior with other individuals. It is not known, however, what each animal needs to learn in order to achieve and maintain synchronized call patterns with others. To study this process, we have developed a vocal robot that can be programed to generate call patterns or to sense a bird's contact (short) calls and respond with precisely timed call answers. By varying the robot's vocal behavior, including call timing and rhythm, we tested how interacting zebra finches adapt …


Matrix Stiffness Regulates Glial Cell Morphology And Differentiation, Mateusz M. Urbanski Sep 2015

Matrix Stiffness Regulates Glial Cell Morphology And Differentiation, Mateusz M. Urbanski

Dissertations, Theses, and Capstone Projects

Studies from our laboratory have shown that inhibition of non-muscle myosin II (NMII) activity has opposite effects on the formation of myelin by oligodendrocytes (OL), the myelinating glia of the central nervous system (CNS) and Schwann cells (SC), which perform the same function in the peripheral nervous system (PNS). The decrease of NMII activity in SC impairs their ability to establish polarity and myelinate, while its inhibition in OL enhances process branching and increases the amount of myelin formed in vitro an in vivo. A growing number of studies have shown that NMII also plays a role in the ability …


Diversity And Phylogeography Of Anurans Of The Highlands Of Ethiopia, Xenia Freilich Sep 2015

Diversity And Phylogeography Of Anurans Of The Highlands Of Ethiopia, Xenia Freilich

Dissertations, Theses, and Capstone Projects

Located in Eastern Africa, Ethiopia is a country of unique geological features, among them the largest continuous Afro-alpine zone in Africa and the Great Rift Valley (GRV). The GRV formation began ~20 mya; it is a fault system that splits the central Ethiopian dome in two separate highland systems (Baker et al., 1972, Chorowicz, 2005). In spite of the general assumption that the GRV has played a major role in shaping the biodiversity of the country, its influence has not been fully investigated, as only a handful of studies have addressed its impact on the phylogeographic and evolutionary history of …


Systematic Studies Of Elaphoglossum Section Polytrichia (Dryopteridaceae), Fernando Bittencourt De Matos Sep 2015

Systematic Studies Of Elaphoglossum Section Polytrichia (Dryopteridaceae), Fernando Bittencourt De Matos

Dissertations, Theses, and Capstone Projects

Elaphoglossum is the largest genus of the largest family of ferns, the Dryopteridaceae. It has over 600 species distributed in the temperate and tropical regions of the world, but it is especially diverse in the Neotropics, where ca. 80% of the species occur. Morphologically, the genus is usually characterized by simple entire leaves, free veins, acrostichoid sori, and phyllopodia. One of the major clades within Elaphoglossum is the "subulate-scaled clade," which includes all species with subulate scales on the leaves. These scales are often patent and enrolled lengthwise, imparting a bristly or shaggy appearance to the plants. Previous studies have …


The Role Of The Vta Nmda Receptors, Vta Da Cells And Vta Terminal Regions In Reward-Related Learning, Karen Kest Sep 2015

The Role Of The Vta Nmda Receptors, Vta Da Cells And Vta Terminal Regions In Reward-Related Learning, Karen Kest

Dissertations, Theses, and Capstone Projects

Reward-related learning occurs when an initially neutral stimulus acquires the capacity to elicit responses similar to an unconditioned stimulus (US) with which it is associated, in which case the stimulus now functions as a conditioned stimulus (CS). The mechanisms whereby stimuli come to function as CSs are not fully understood and comprise the theme of this dissertation. We have previously proposed that coincident signals from an unconditioned and the eventual conditioned stimulus (US and CS) signals on dopamine (DA) cells of the ventral tegmental area (VTA) leads to strengthening of CS synapses, allowing the CS to acquire the ability to …


Climate, Resource Phenology, And Demographic Population Structure Impacts On Songbird Habitat Quality, Ashley Ozelski Sep 2015

Climate, Resource Phenology, And Demographic Population Structure Impacts On Songbird Habitat Quality, Ashley Ozelski

Dissertations, Theses, and Capstone Projects

Monitoring bird populations becomes more complex as climate change alters species' relationships with their habitats. The presence of a species does not necessarily indicate a thriving population; in fact, we expect to see changes in demography and nest success before extinction at a site. Here, I first model aspects of demography as a proxy for habitat quality across a large portion of a species' range, using land cover and climate predictors. I show a gradient of high to low habitat quality from north to south within the range for the Yellow Warbler (Setophaga petechia), with summer temperature and …


Geospatial Resolution Of Human And Bacterial Diversity With City-Scale Metagenomics, Ebrahim Afshinnekoo, Cem Meydan, Shanin Chowdhury, Dyala Jaroudi, Collin Boyer, Nick Bernstein, Julia M. Maritz, Darryl Reeves, Jorge Gandara, Sagar Chhangawala, Sofia Ahsanuddin, Amber Simmons, Timothy Nessel, Bharathi Sundaresh, Elizabeth Pereira, Ellen Jorgensen, Sergios-Orestis Kolokotronis, Nell Kirchberger, Isaac Garcia, David Gandara, Sean Dhanraj, Tanzina Nawrin, Yogesh Saletore, Noah Alexander, Priyanka Vijay, Elizabeth M. Hénaff, Paul Zumbo, Michael Walsh, Gregory D. O'Mullan, Scott Tighe, Joel T. Dudley, Anya Dunaif, Sean Ennis, Eoghan O'Halloran, Tiago R. Magalhaes, Braden Boone, Angela L. Jones, Theodore R. Muth, Katie Schneider Paolantonio, Elizabeth Alter, Eric E. Schadt, Jeanne Garbarino, Robert J. Prill, Jane M. Carlton, Shawn Levy, Christopher E. Mason Jul 2015

Geospatial Resolution Of Human And Bacterial Diversity With City-Scale Metagenomics, Ebrahim Afshinnekoo, Cem Meydan, Shanin Chowdhury, Dyala Jaroudi, Collin Boyer, Nick Bernstein, Julia M. Maritz, Darryl Reeves, Jorge Gandara, Sagar Chhangawala, Sofia Ahsanuddin, Amber Simmons, Timothy Nessel, Bharathi Sundaresh, Elizabeth Pereira, Ellen Jorgensen, Sergios-Orestis Kolokotronis, Nell Kirchberger, Isaac Garcia, David Gandara, Sean Dhanraj, Tanzina Nawrin, Yogesh Saletore, Noah Alexander, Priyanka Vijay, Elizabeth M. Hénaff, Paul Zumbo, Michael Walsh, Gregory D. O'Mullan, Scott Tighe, Joel T. Dudley, Anya Dunaif, Sean Ennis, Eoghan O'Halloran, Tiago R. Magalhaes, Braden Boone, Angela L. Jones, Theodore R. Muth, Katie Schneider Paolantonio, Elizabeth Alter, Eric E. Schadt, Jeanne Garbarino, Robert J. Prill, Jane M. Carlton, Shawn Levy, Christopher E. Mason

Publications and Research

The panoply of microorganisms and other species present in our environment influence human health and disease, especially in cities, but have not been profiled with metagenomics at a city-wide scale. We sequenced DNA from surfaces across the entire New York City (NYC) subway system, the Gowanus Canal, and public parks. Nearly half of the DNA (48%) does not match any known organism; identified organisms spanned 1,688 bacterial, viral, archaeal, and eukaryotic taxa, which were enriched for harmless genera associated with skin (e.g., Acinetobacter). Predicted ancestry of human DNA left on subway surfaces can recapitulate U.S. Census demographic data, and bacterial …


Lesion-Specific Immune Response In Granulomas Of Patients With Pulmonary Tuberculosis: A Pilot Study, Selvakumar Subbian, Liana Tsenova, Mi-Jeong Kim, Helen C. Wainwright, Annalie Visser, Nirmalya Bandyopadhyay, Joel S. Bader, Petros C. Karakousis, Gabriele B. Murrmann, Linda-Gail Bekker, David G. Russell, Gilla Kaplan Jul 2015

Lesion-Specific Immune Response In Granulomas Of Patients With Pulmonary Tuberculosis: A Pilot Study, Selvakumar Subbian, Liana Tsenova, Mi-Jeong Kim, Helen C. Wainwright, Annalie Visser, Nirmalya Bandyopadhyay, Joel S. Bader, Petros C. Karakousis, Gabriele B. Murrmann, Linda-Gail Bekker, David G. Russell, Gilla Kaplan

Publications and Research

The formation and maintenance of granulomas is central to the host response to Mycobacterium tuberculosis (Mtb) infection. It is widely accepted that the lungs of patients with tuberculosis (TB) usually contain multiple infection foci, and that the granulomas evolve and differentiate independently, resulting in considerable heterogeneity. Although gene expression profiles of human blood cells have been proposed as biomarkers of Mtb infection and/or active disease, the immune profiles of discrete lesion types has not been studied extensively. Using histology, immunopathology and genome-wide transcriptome analysis, we explored the immunological profile of human lung TB granulomas. We show that although the different …


Inhibition Of Cell Differentiation In Bacillus Subtilis By Pseudomonas Protegens, Matthew J. Powers, Edgardo Sanabria-Valentín, Albert A. Bowers, Elizabeth A. Shanka Jul 2015

Inhibition Of Cell Differentiation In Bacillus Subtilis By Pseudomonas Protegens, Matthew J. Powers, Edgardo Sanabria-Valentín, Albert A. Bowers, Elizabeth A. Shanka

Publications and Research

Interspecies interactions have been described for numerous bacterial systems, leading to the identification of chemical compounds that impact bacterial physiology and differentiation for processes such as biofilm formation. Here, we identified soil microbes that inhibit biofilm formation and sporulation in the common soil bacterium Bacillus subtilis. We did so by creating a reporter strain that fluoresces when the transcription of a biofilm-specific gene is repressed. Using this reporter in a coculture screen, we identified Pseudomonas putida and Pseudomonas protegens as bacteria that secrete compounds that inhibit biofilm gene expression in B. subtilis. The active compound produced by P. protegens was …


Use Of Rna Sequencing To Evaluate Rheumatic Disease Patients, Eugenia Giannopoulou, Olivier Elemento, Lionel B. Ivashkiv Jul 2015

Use Of Rna Sequencing To Evaluate Rheumatic Disease Patients, Eugenia Giannopoulou, Olivier Elemento, Lionel B. Ivashkiv

Publications and Research

Studying the factors that control gene expression is of substantial importance for rheumatic diseases with poorly understood etiopathogenesis. In the past, gene expression microarrays have been used to measure transcript abundance on a genome-wide scale in a particular cell, tissue or organ. Microarray analysis has led to gene signatures that differentiate rheumatic diseases, and stages of a disease, as well as response to treatments. Nowadays, however, with the advent of next-generation sequencing methods, massive parallel sequencing of RNA tends to be the technology of choice for gene expression profiling, due to several advantages over microarrays, as well as for the …


Molecular Diversity And Gene Evolution Of The Venom Arsenal Of Terebridae Predatory Marine Snails, Juliette Gorson, Girish Ramrattan, Aida Verdes, Elizabeth M. Wright, Yuri Kantor, Ramakrishnan Rajaram Srinivasan, Raj Musunuri, Daniel Packer, Gabriel Albano, Wei-Gang Qiu, Mandë Holford May 2015

Molecular Diversity And Gene Evolution Of The Venom Arsenal Of Terebridae Predatory Marine Snails, Juliette Gorson, Girish Ramrattan, Aida Verdes, Elizabeth M. Wright, Yuri Kantor, Ramakrishnan Rajaram Srinivasan, Raj Musunuri, Daniel Packer, Gabriel Albano, Wei-Gang Qiu, Mandë Holford

Publications and Research

Venom peptides from predatory organisms are a resource for investigating evolutionary processes such as adaptive radiation or diversification, and exemplify promising targets for biomedical drug development. Terebridae are an understudied lineage of conoidean snails,which also includes cone snails and turrids. Characterization of cone snail venompeptides, conotoxins, has revealed a cocktail of bioactive compounds used to investigate physiological cellular function, predator-prey interactions, and to develop novel therapeutics. However, venom diversity of other conoidean snails remains poorly understood. The present research applies a venomics approach to characterize novel terebrid venom peptides, teretoxins, from the venom gland transcriptomes of Triplostephanus anilis and Terebra …


Testing Visual Ecology Hypotheses In Avian Brood Parasite-Host Systems: The Role Of Uv-Light Perception And Egg-Nest Contrast In Foreign Egg Rejection, Zachary Aidala May 2015

Testing Visual Ecology Hypotheses In Avian Brood Parasite-Host Systems: The Role Of Uv-Light Perception And Egg-Nest Contrast In Foreign Egg Rejection, Zachary Aidala

Dissertations, Theses, and Capstone Projects

Color signals are highly important features of animal communication systems, particularly among birds, which possess exquisitely complex visual perception systems. Birds possess tetrachromatic vision, and some species are sensitive to ultraviolet (UV) wavelengths. Because human and avian visual systems dramatically differ (i.e. humans are not sensitive to UV wavelengths), biologically relevant sensory models are necessary to accurately assess the function of avian color signals. In this dissertation, I primarily use brood parasite-host interactions as a model for studying the behavioral function of avian-perceivable visual stimuli. In Chapter 1, I review the importance of employing biologically relevant sensory-perceptual visual models when …


Control Of Cell Cycle Progression By Mtor, Amrita Chatterjee May 2015

Control Of Cell Cycle Progression By Mtor, Amrita Chatterjee

Dissertations, Theses, and Capstone Projects

Over the past few years it has become apparent that cancer cells require the activation of a set of intra-cellular signals that promote cell cycle progression and survival. One of the most common survival signals activated in human cancers is mediated by mTOR -the mammalian target of rapamycin. mTOR is a critical nutrient and energy sensor in cells that lets the cell know that there is sufficient material available for a cell to double its mass and divide. mTOR causes the phosphorylation of downstream targets ribosomal subunit S6 kinase and eukaryotic initiation factor 4E (eIF4E) binding protein-1 (4E-BP1), which promotes …


Nuclear Pore Protein Nup211 Is Essential For Cell Cycle Progression And Cell Shape Maintenance In Fission Yeast, Ayisha R. Sookdeo May 2015

Nuclear Pore Protein Nup211 Is Essential For Cell Cycle Progression And Cell Shape Maintenance In Fission Yeast, Ayisha R. Sookdeo

Dissertations, Theses, and Capstone Projects

The nuclear pore complexes (NPCs) are large multi-protein channels that traverse the nuclear envelope and mediate nucleo-cytoplasmic transport. Proteomic studies have revealed that NPCs are composed of about thirty different proteins called nucleoporins. I explored a particular nucleoporin, Nup211, in fission yeast. nup211 is an essential gene; its deletion is lethal and causes morphological defects. In this study, I characterized the cell morphological defects caused by the down-regulation of Nup211 and found that restoring the N-terminal domain of Nup211 was sufficient to rescue the lethal phenotype and partially suppress the morphological defects. Additionally, I investigated the role Nup211 plays in …


Phylogeography Of Southeast Asian Flying Foxes (Chiroptera: Pteropodidae: Pteropus), Susan Man Shu Tsang May 2015

Phylogeography Of Southeast Asian Flying Foxes (Chiroptera: Pteropodidae: Pteropus), Susan Man Shu Tsang

Dissertations, Theses, and Capstone Projects

Flying foxes (Pteropus) are a genus of Old World fruit bats that are important seed dispersers and pollinators for plants native to the 200,000+ islands in Southeast Asia, yet they are some of the most poorly known bats in the world. They comprise some of the largest known bat species, and are morphologically relatively conserved on the genus level. Pteropus is the most species-rich genus within Pteropodidae, though the origin for this diversity remains incompletely understood. In Chapter 1, I discuss the importance of Pteropus to the ecosystem and as reservoir hosts. In Chapter 2, a molecular phylogeny is presented …


Phylogenomic Identification Of Regulatory Sequences In Bacteria: An Analysis Of Statistical Power And An Application To Borrelia Burgdorferi Sensu Lato, Che I. Martin, Tika Y. Sukarna, Saymon Akther, Girish Ramrattan, Pedro Pagan, Lia Di, Emmanuel F. Mongodin, Claire M. Fraser, Steven E. Schutzer, Benjamin J. Luft, Sherwood R. Casjens, Wei-Gang Qiu Apr 2015

Phylogenomic Identification Of Regulatory Sequences In Bacteria: An Analysis Of Statistical Power And An Application To Borrelia Burgdorferi Sensu Lato, Che I. Martin, Tika Y. Sukarna, Saymon Akther, Girish Ramrattan, Pedro Pagan, Lia Di, Emmanuel F. Mongodin, Claire M. Fraser, Steven E. Schutzer, Benjamin J. Luft, Sherwood R. Casjens, Wei-Gang Qiu

Publications and Research

Phylogenomic footprinting is an approach for ab initio identification of genome-wide regulatory elements in bacterial species based on sequence conservation. The statistical power of the phylogenomic approach depends on the degree of sequence conservation, the length of regulatory elements, and the level of phylogenetic divergence among genomes. Building on an earlier model, we propose a binomial model that uses synonymous tree lengths as neutral expectations for determining the statistical significance of conserved intergenic spacer (IGS) sequences. Simulations show that the binomial model is robust to variations in the value of evolutionary parameters, including base frequencies and the transition-to-transversion ratio. We …


Improved Evidence-Based Genome-Scale Metabolic Models For Maize Leaf, Embryo, And Endosperm, Samuel M. D. Seaver, Louis M. T. Bradbury, Océane Frelin, Raphy Zarecki, Eytan Ruppin, Andrew D. Hanson, Christopher S. Henry Mar 2015

Improved Evidence-Based Genome-Scale Metabolic Models For Maize Leaf, Embryo, And Endosperm, Samuel M. D. Seaver, Louis M. T. Bradbury, Océane Frelin, Raphy Zarecki, Eytan Ruppin, Andrew D. Hanson, Christopher S. Henry

Publications and Research

There is a growing demand for genome-scale metabolic reconstructions for plants, fueled by the need to understand the metabolic basis of crop yield and by progress in genome and transcriptome sequencing. Methods are also required to enable the interpretation of plant transcriptome data to study how cellular metabolic activity varies under different growth conditions or even within different organs, tissues, and developmental stages. Such methods depend extensively on the accuracy with which genes have been mapped to the biochemical reactions in the plant metabolic pathways. Errors in these mappings lead to metabolic reconstructions with an inflated number of reactions and …


Protein Sectors: Statistical Coupling Analysis Versus Conservation, Tiberiu Teşileanu, Lucy J. Colwell, Stanislas Leibler Feb 2015

Protein Sectors: Statistical Coupling Analysis Versus Conservation, Tiberiu Teşileanu, Lucy J. Colwell, Stanislas Leibler

Publications and Research

Statistical coupling analysis (SCA) is a method for analyzing multiple sequence alignments that was used to identify groups of coevolving residues termed “sectors”. The method applies spectral analysis to a matrix obtained by combining correlation information with sequence conservation. It has been asserted that the protein sectors identified by SCA are functionally significant, with different sectors controlling different biochemical properties of the protein. Here we reconsider the available experimental data and note that it involves almost exclusively proteins with a single sector. We show that in this case sequence conservation is the dominating factor in SCA, and can alone be …


The Regulatory Function Of Sphingosine-1-Phosphate Signaling Axis On Regulatory T Cells In Colorectal Cancer, Andrew V. Nguyen, Yuan-Yuan Wu, Elaine Y. Lin Feb 2015

The Regulatory Function Of Sphingosine-1-Phosphate Signaling Axis On Regulatory T Cells In Colorectal Cancer, Andrew V. Nguyen, Yuan-Yuan Wu, Elaine Y. Lin

Publications and Research

In tumors associated with inflammation such as inflammatory bowel disease (IBD) and colorectal cancer (CRC), high numbers of regulatory T cells (Tregs) are associated with both favorable and poor prognoses. The functions of Tregs in CRC remain elusive and have yet to be clearly defined. With new evidence supporting many subsets of Tregs, the research on the development and functions of these cells has begun to come to fruition. The sphingosine 1 phosphate (S1P) pathway was recently reported to regulate the development and function of regulatory T cells. This pathway may shine new light into the pleiotropic nature of these …


Tcr Alpha Lcr And Non-Lcr Cis-Elements Contributing To Tissue Specific Expression Of The Tcr Alpha Gene In Thymic And Peripheral T Cells, Martina Kucerova-Levisohn Feb 2015

Tcr Alpha Lcr And Non-Lcr Cis-Elements Contributing To Tissue Specific Expression Of The Tcr Alpha Gene In Thymic And Peripheral T Cells, Martina Kucerova-Levisohn

Dissertations, Theses, and Capstone Projects

Orchestrated expression of multiple genes residing in the complex TCRα/δ/Dad1 locus requires tight control from multiple cis-acting elements. The TCRα locus control region (LCR), is positioned between TCRα and Dad1 gene, and has been implicated in the differential expression of both genes. In this study, we focus our work on the hypersensitive site (HS)1 prime (HS1'), located 3' of the classical Eα enhancer, within the TCRα LCR. We investigated its non- redundant role in TCRα expression in thymic and peripheral T cells as assayed by in vivo and in vitro studies. Furthermore, formation of HS1' in both lymphoid and …