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Full-Text Articles in Life Sciences

Variations In The Invertebrate Communities Of Wild Cape Cod Cranberry Bogs, Barbara Wagner Mar 2016

Variations In The Invertebrate Communities Of Wild Cape Cod Cranberry Bogs, Barbara Wagner

Masters Theses

As a species domesticated only in the last century, agricultural cranberry plants (Vaccinium macrocarpon) remain little removed from their wild relatives. Thus, it is a potential model species for studies of the earliest stages of domestication; however, there is little available quantitative information on its wild population biology and ecology. As such information is vital to studies of the ecological changes occurring during domestication, the purpose of this study was to consolidate the relevant knowledge available and conduct a preliminary search for patterns in the invertebrate communities of wild bogs. The alpha diversity was found to be greater than the ...


The Identification Of Notch1 Functional Domains Responsible For Its Physical Interaction With Pkcθ, Wesley D. Rossiter Mar 2016

The Identification Of Notch1 Functional Domains Responsible For Its Physical Interaction With Pkcθ, Wesley D. Rossiter

Masters Theses

The adaptive immune system is a complex network of cells that protect the body from invasion by foreign pathogens. Crucial to the function of the adaptive immune system is the activation, proliferation and differentiation of T cells in response to foreign pathogen presentation by antigen presenting cells. T cell activation is driven through different signaling pathways that are dependent on phosphorylation of substrates by kinases. In the PLC pathway that activates the il2 gene program, Protein Kinase C-q (PKCq) and Notch1 localize to the immunological synapse and help drive the signaling cascade that leads to robust T cell activation. It ...


Influence Of Inoculum Preparation Upon Sensitivity Of Common Food Borne Pathogens To Emulsion Based Antimicrobials, Dillon Sd Murray Mar 2016

Influence Of Inoculum Preparation Upon Sensitivity Of Common Food Borne Pathogens To Emulsion Based Antimicrobials, Dillon Sd Murray

Masters Theses

Antimicrobial optimization procedures use the most resistant bacterial culture that could be present in the food to determine the levels of treatment needed to ensure safety. These procedures usually only focus on one method of preparing these inoculums for testing despite prior research showing that the preparation of the culture can influence how the culture reacts to a treatment. In this work, planktonic cells grown in a liquid media and sessile cells grown on a similar solid media were subjected to identical emulsion based antimicrobial systems. The cultures were monitored over time and their numbers periodically enumerated. Weibullian destruction models ...


Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson Mar 2016

Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson

Masters Theses

Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite loci from ...


Studies Of Kinetochore Mechanobiology In Drosophila, Stuart Cane Mar 2016

Studies Of Kinetochore Mechanobiology In Drosophila, Stuart Cane

Doctoral Dissertations

Kinetochores are large multiprotein structures through which chromosomes engage with the microtubules of the mitotic spindle. All kinetochore pairs must ultimately adopt a bioriented configuration, with their associated sister chromatids linked to opposite spindle poles and poised to segregate equally between two daughter cells. Erroneous, non-bioriented attachments that are left uncorrected lead to chromosome mis-segregation, producing aneuploid daughter cells with unequal numbers of chromosomes. Before anaphase onset, bioriented attachments are selectively stabilized whereas non-bioriented attachments remain unstable and are eliminated. This error correction process relies heavily on the extent of outer kinetochore phosphorylation by an Aurora B kinase activity centered ...


Exploring The Impact Of The E. Coli Proteostasis Network On The Folding Fate Of Proteins With Different Intrinsic Biophysical Properties, Kristine Faye R. Pobre Mar 2016

Exploring The Impact Of The E. Coli Proteostasis Network On The Folding Fate Of Proteins With Different Intrinsic Biophysical Properties, Kristine Faye R. Pobre

Doctoral Dissertations

The three-dimensional (3D) native structure of most proteins is crucial for their functions. Despite the complex cellular environment and the variety of challenges that proteins experience as they fold, proteins can still fold to their native states with high fidelity. The reason for this is the presence of the cellular proteostasis network (PN), consisting of molecular chaperones and degradation enzymes, that collaborates to maintain proteostasis, in which the necessary levels of functional proteins are optimized. Although extensive research has been carried out on the mechanisms of individual components of the proteostasis network, little is known about how these components contribute ...


Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu Mar 2016

Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu

Doctoral Dissertations

Corticotropin-releasing factor (CRF) is the major peptide involved in regulating the body’s autonomic, hormonal, and behavioral responses to stress. Cells that produce and release this peptide are widely distributed throughout the brain. This dissertation focuses on a specific population of CRF cells residing in the medial prefrontal cortex (mPFC) that could potentially influence a number of higher order functions through modulation of local circuits. The prefrontal cortex is known to function sub-optimally in patients suffering from various stress-related psychiatric conditions including alcohol use disorder (AUD), and dysregulated CRF signaling may be an underlying mechanism. Surprisingly little is known about ...


Mammalian Egg Activation: The Roles Of Trpv3 Channels And Plcz1, Hoi Chang Lee Mar 2016

Mammalian Egg Activation: The Roles Of Trpv3 Channels And Plcz1, Hoi Chang Lee

Doctoral Dissertations

Calcium channels at the plasma membrane have been suggested to mediate Ca2+ influx during egg activation. The transient receptor potential (TRP) Ca2+ channel, TRPV3, is differentially expressed in oocytes during maturation, being fully active at MII stage. Specific stimulation of TRPV3 channels in mouse eggs promotes Ca2+ influx sufficient to induce egg activation and parthenogenesis. In chapter 2, we explore the function and distribution dynamics of the TRPV3 channel protein during oocyte maturation. Using dsRNA, TrpV3 overexpression, and inhibitors of protein synthesis, we modified the native expression of the channel and showed that the TRPV3 protein is ...


Optimization Of The Fabrication, Stability, And Performance Of Food Grade Nanoemulsions With Low And High Energy Methods, Jennifer Komaiko Mar 2016

Optimization Of The Fabrication, Stability, And Performance Of Food Grade Nanoemulsions With Low And High Energy Methods, Jennifer Komaiko

Doctoral Dissertations

There is interest in the production of emulsions by low-energy methods because no expensive equipment is required thus making emulsion formation inexpensive and simple to implement. The goal of this research is to establish the major factors that affect emulsion formation using low-energy methods and possible applications of the emulsions and nanoemulsions formed by this method. Lastly, the use of natural emulsifiers with low- and high-energy methods was investigated.

Initially, formation of nanoemulsions using isothermal low energy methods was investigated with a model system (hexadecane, Brij 30). Preliminary experiments showed that nanoemulsions could only be formed when the surfactant was ...


Evolvability Of The Skull: A Study Of Genetic Basis And Integration In The Teleost Craniofacial Skeleton, Yinan Hu Mar 2016

Evolvability Of The Skull: A Study Of Genetic Basis And Integration In The Teleost Craniofacial Skeleton, Yinan Hu

Doctoral Dissertations

As the field of evolutionary biology pivots away from a gene-centric view of how adaptive evolution proceeds, renewed emphasis is placed on the origin of phenotypic variation. Understanding the developmental processes that underlie the production of novel traits, and how they might influence evolvability, is considered a primary goal in the on-going “extended evolutionary synthesis”. The following dissertation explores these questions in the context of adaptive radiations in fish, with a focus on morphological variation in the craniofacial skeleton. Specifically, the first chapter investigates the genetic and developmental basis of shape (co-)variation in the feeding apparatus of African cichlid ...


The Influence Of Musculoskeletal Geometry On The Metabolic Cost Of Pedaling, Lex Gidley Mar 2016

The Influence Of Musculoskeletal Geometry On The Metabolic Cost Of Pedaling, Lex Gidley

Doctoral Dissertations

The human musculoskeletal system consists of several muscles crossing each joint. In the human lower limb, most major muscles cross either one or two joints; labeled as uniarticular or biarticular muscles, respectively. The major biarticular muscles of the leg are the rectus femoris, hamstrings, and gastrocnemius. Several suggestions have been proposed as to how biarticular muscles may reduce the metabolic cost of human movement. Using experimental protocols, it is difficult to address the energetic effects of biarticular muscles, as individual muscle contributions to human movement cannot be measured and there is no way to determine what the effect might be ...


The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto Mar 2016

The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto

Doctoral Dissertations

Thorough insight into a protein’s structure is necessary to understand how it functions and what goes wrong when it malfunctions. The structure of proteins, however, is not easily analyzed. The analysis must take place under a narrow range of conditions or risk perturbing the very structure being probed. Furthermore, the wide diversity in size and chemistry possible in proteins significantly complicates this analysis. Despite this numerous methods have been developed in order to analyze protein structure. In this work, we demonstrate that mass spectrometry (MS)-based techniques are capable of characterizing the structure of particularly challenging proteins. This is ...


The Role Of Notch3 Signaling In T Helper Cell Differentiation And Induction Of Eae, Furkan Ayaz Mar 2016

The Role Of Notch3 Signaling In T Helper Cell Differentiation And Induction Of Eae, Furkan Ayaz

Doctoral Dissertations

Th1 and Th17 are subsets of CD4+ T cells or T helper cells (Th). Th cells are the major adaptive immune cells involved in inflammation during the development of Multiple Sclerosis (MS). MS is a neurodegenerative autoimmune disease and one mouse model of the disease is Experimental Autoimmune Encephalomyelitis (EAE). Development and differentiation of Th1 and Th17 cells are regulated by the Notch family of trans-membrane proteins (Notch1, 2, 3 and 4). We and others have shown that pharmacological inhibition of Notch activity impairs Th1 and Th17 differentiation as well as development of EAE. However, it is not known which ...


Fish Oil Nanoemulsions: Optimization Of Physical And Chemical Stability For Food System Applications, Rebecca M. Walker Feb 2016

Fish Oil Nanoemulsions: Optimization Of Physical And Chemical Stability For Food System Applications, Rebecca M. Walker

Masters Theses

Emulsion-based delivery systems offer many potential benefits for incorporating omega-3 oils into foods and beverages. Nanoemulsions are emulsion-based delivery systems that are gaining popularity because of their ease of preparation, small particle size, relatively high stability, high bioavailability, and production of optically transparent emulsions. Fish oil (FO) nanoemulsions are potentially more susceptible to lipid oxidation because of their high degree of lipid unsaturation, high surface area of exposed lipids, and greater light penetration. In the first study, spontaneous emulsification, a low-energy method, was used to fabricate FO nanoemulsions. The influence of surfactant-to-oil-ratio (SOR) on particle size, turbidity, and physical stability ...


Uncovering The Genetic Basis For Biofuel-Related Traits In Brachypodium Distachyon, Scott J. Lee Jan 2016

Uncovering The Genetic Basis For Biofuel-Related Traits In Brachypodium Distachyon, Scott J. Lee

Doctoral Dissertations

Biofuels derived from plant biomass present a promising avenue to address the negative aspects of fossil-fuel dependence. The sustainability of biofuel production relies in part on the efficient degradation of lignocellulosic feedstocks. In order to capitalize on the potential of lignocellulosic biofuels, the genes underlying natural genetic variation for conversion efficiency must be determined. We have developed a robust and high-throughput assay to measure feedstock quality using the anaerobic bacterium Clostridium phytofermentans. We have measured biomass accumulation phenotypes and utilized this assay to perform quantitative trait locus (QTL) mapping and a genome-wide association study (GWAS) in the model grass species ...