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The Role Of Gap-43 Phosphorylation In Axon Behavior In The Developing Zebrafish Visual System, Jennifer Forecki

Theses and Dissertations

Developing neurons extend processes to specific targets and establish connections that are essential for future function of the nervous system. One of these processes, the axon, has a motile tip called a growth cone that rearranges its membrane-associated actin cytoskeleton to turn toward or away from environmental guidance cues. Growth associated protein 43 (GAP-43) is one of the most abundant proteins associated with axonal growth cone membranes and is known to modulate the formation and stability of the actin cytoskeleton during axon guidance. Protein kinase C (PKC)-mediated phosphorylation of GAP-43 on serine 42 regulates its interactions with actin. Phosphorylated GAP-43 …

Taking Tone Into Account: Cognitive Neuroscientific Investigations Of Mandarin Chinese Spoken Word Processing, Jeffrey G. Malins

Electronic Thesis and Dissertation Repository

To date, theories of how humans recognize spoken words have yet to account for tonal languages such as Mandarin Chinese. One reason for this is that we know relatively little about how native speakers of tonal languages process spoken words in the brain. This dissertation addresses this problem by examining Mandarin spoken word processing in both adult native speakers and typically developing children. In adults, functional magnetic resonance imaging (fMRI) was used to assess the extent to which the brain regions involved in processing tonal information are distinct from those involved in vowel processing (Chapter 2), while event related potentials …

Developmental Characterization Of Tissue Inhibitor Of Metalloproteinase Domain Functions In Xenopus Laevis, Michelle A. Nieuwesteeg

Electronic Thesis and Dissertation Repository

During development the extracellular matrix is cleaved and remodeled to facilitate the large-scale cell rearrangements that are necessary for processes like gastrulation, neurulation, angiogenesis and organogenesis. ECM remodeling occurs primarily through secreted enzymes called matrix metalloproteinases (MMPs). Regulation of MMP activity is achieved through the tissue inhibitor of metalloproteinases (TIMPs), a small family of secreted proteins that bind MMPs in a 1:1 manner to inhibit their activity. Although TIMPs were originally characterized based on their MMP-inhibitory activities, in vitro studies have revealed that TIMPs are multifunctional proteins, with structurally and functionally distinct N- and C-terminal domains. TIMP N-terminal domains bind …

Confocal Microscopy Study Of The Embryonic Development Of The Viviparous Nemertean Prosorhochmus Americanus Reveals Larval Features Supporting Indirect Development In Hoplonemerteans, S Tyler Spindle

Theses and Dissertations

Recent studies of hoplonenemertean planuliform larvae have clarified their development and provided insight into larval evolution within the phylum. However, an assessment of viviparous development using modern techniques is lacking. To help facilitate a comprehensive comparative evaluation of developmental diversity within hoplonemerteans, we have conducted a confocal laser scanning microscopy investigation of the development in Prosorhochmus americanus, one of the few viviparous hoplonemertean species. Phalloidin staining provides evidence of a modified transitory larval epidermis, and reveals that the foregut, midgut, proboscis, central nervous system, and body wall musculature form early in development, consistent with observations for planktonic and encapsulated hoplonemertean …

Alternations Of Nmda And Gabab Receptor Function In Development: A Potential Animal Model Of Schizophrenia, Monica Bolton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Schizophrenia is a debilitating mental disorder that affects up to 3% of the world population. The behavioral symptoms are categorized into positive and negative symptoms, which appear during late adolescence/early adulthood. Unfortunately, the underlying cellular and molecular mechanisms of the disease are poorly understood. Several hypotheses exist to explain mechanisms contributing to these behavioral alterations. One model proposes that a reduced function of the NMDA glutamate receptor on specific GABAergic interneurons may be responsible for deficits in schizophrenia. Post-mortem investigations provide evidence of reductions in both glutamate and GABA-related proteins in patients with schizophrenia. Further, GABAergic interneurons that are activated …

The Effects Of Soil Ph And Composition On Blacklegged Tick Molting Success Avian Window Strike Mortality On Union College Campus, Kaleigh Ahern

Honors Theses

The blacklegged tick (Ixodes scapularis) is the one of the most significant vectors of infectious disease in the world and most notorious for its ability to transmit Borrelia burgdorferi, the bacteria that causes Lyme disease. Because both the range of the blacklegged tick and the annual incidence of Lyme disease have been increasing in North America over the past several decades, it is becoming increasingly important to better understand how environmental factors contribute to blacklegged tick survival. Past studies have shown that these factors include precipitation levels, extent of groundcover, plant and animal community composition, temperature, and soil type. Because …

Evaluation Of Survey Methods And Development Of Species Distribution Models For Kit Foxes In The Great Basin Desert, Stephen J. Dempsey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Historically, kit foxes (Vulpes macrotis) once occupied the desert and semi-arid regions of southwestern North America, ranging from Idaho to central Mexico. Their range-wide decline has warranted the kit fox to be designated as a state sensitive species in Utah. Once considered the most abundant carnivore in western Utah, the kit fox has been in steep decline over the past decade, creating a demand to determine kit fox presence in the Great Basin desert. Currently there is little consensus on which survey methodology is best for detecting kit fox presence. We tested 4 survey methods (scat deposition, scent …

Nutritional And Economic Analysis Of Small-Scale Agriculture In Imbabura, Ecuador, Jake Erickson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Intervention projects in the developing world normally aim to satisfy either the nutritional needs of a group, or advancing the economic stability, but not both. One of the many issues that may arise by narrowly focusing and creating an aid program is that although a group may be fed, they are not equipped to mitigate risks that will arise after project completion and thus continue or revert back to a malnourished state. A bridge is required to join the economic and nutritional programs to create aid interventions that are sustainable past the point of donor separation.

This paper proposes the …

Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya

Legacy Theses & Dissertations (2009 - 2024)

The Quechua populations have inhabited the Andes for hundreds of generations. The ability to thrive in this hostile environment, leading an active and healthy life has generated research questions about the special phenotype of Andean highlanders compared to their sea-level counterparts, such as their higher pulmonary volumes and their outstanding work capacity in spite of the challenge of oxygen transport and delivery in hypoxia. In high altitude natives, there have been two main explanations for the origins of the aforementioned traits: genetic adaptation through natural selection and developmental adaptation through the exposure to hypoxia during growth.

The Role Of Progesterone Receptor In The Development Of The Mesocortical Dopaminergic Pathway, Jari Willing

Legacy Theses & Dissertations (2009 - 2024)

The mesocortical dopaminergic pathway, comprised of projections from the ventral tegmental area (VTA) to the prefrontal cortex (PFC), mediates many of the most complex forms of cognitive behaviors and has been associated with clinical disorders such as ADHD and schizophrenia. While this circuit continues to develop throughout much of the lifespan, there is a rapid period of maturation, early in development, in which this circuit is highly sensitive to disruption. Steroid hormone receptors are powerful transcription factors, capable of affecting a variety of neurodevelopmental processes and are expressed in many regions throughout the developing brain. Specifically, the nuclear progesterone receptor …

New Tools For Real-Time Study Of Embryonic Development, Lauren M. Browning

Theses and Dissertations in Biomedical Sciences

Embryonic development represents one of the most complex and dynamic cellular processes in biology, and plays vital roles in understanding of functions of embryonic stem cells (ESCs) and design of ESC-based therapy. Conventional assays and fluorescence-based imaging methods have been widely used for the study of embryonic development. These conventional methods cannot effectively provide spatial and temporal resolutions with sufficient sensitivity and selectivity that are required to depict embryonic development in vivo in real-time at single-cell and single-molecule resolutions. In this dissertation, we have developed a wide range of innovative tools for real-time study of embryonic development. These new tools …