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Assessing The Effects Of Habitat On Bird Song Propagation, Braelei Hardt
Assessing The Effects Of Habitat On Bird Song Propagation, Braelei Hardt
Master's Theses
The Acoustic Adaptation Hypothesis (AAH) posits that animal acoustic signals meant for long-range communication should be adapted to transmit well within the habitats in which they evolved. However, comparative studies investigating predictions of the AAH relating to signal form indicate that support for the hypothesis is not universal. Several studies have employed experimental playback approaches to testing signal transmission which can provide complimentary analyses to comparative studies of signal form in the field. Here, I first summarize these experimental playback tests of the AAH in birds, mammals, insects, and anurans, describing the methodologies used in these tests, and assessing the …
The Role Of Gibberellic Acid In Aphid-Plant-Arbuscular Mycorrhizal Fungus Interactions, Drew Olson
The Role Of Gibberellic Acid In Aphid-Plant-Arbuscular Mycorrhizal Fungus Interactions, Drew Olson
Master's Theses
Arbuscular mycorrhizal (AM) fungi form beneficial associations with the roots of most terrestrial plants, which is mostly characterized by increased plant nutrient acquisition (phosphate and nitrogen) by the fungi in exchange for carbon and lipids from the plants. These associations can also enhance plant coping mechanisms to abiotic and biotic stresses. However, insect herbivores, such as aphids, can benefit from AM fungi-plant symbioses by altering plant defenses that are driven mainly by the phytohormones jasmonic acid (JA) and salicylic acid (SA). Nevertheless, other phytohormones can modulate plant defenses by altering the balance of the JA and SA signaling pathways, such …
Effects Of Omega-3 Fatty Acids And Hypoxia On Progesterone Biosynthesis And Mitochondrial Morphology In The Corpus Luteum, Brian Krum
Master's Theses
The corpus luteum is a transient steroidogenic endocrine gland that forms from the remnants of the ovulatory follicle. This gland is responsible for the synthesis and secretion of the hormone progesterone, which is critical for the establishment and maintenance of pregnancy. In a non-pregnant cow, PGF2a is released from the uterus to regress the corpus luteum. However, in the case of pregnancy, the embryo must mitigate PGF2a synthesis to prevent corpus luteum regression. If the embryonic signal is either too late or too weak, uterine PGF2a secretion may result in corpus luteum regression and termination of pregnancy. Omega-3 fatty acids …
Zebrafish Eye Development: Rac And The Creepy Crawlers Of The Eye, Zvi Murry
Zebrafish Eye Development: Rac And The Creepy Crawlers Of The Eye, Zvi Murry
Master's Theses
During vertebrate eye development the optic vesicles protrude from either side of the brain and form the optic cups. As an optic cup starts to surround the lens a groove on the ventral side of the eye forms, known as the choroid fissure (CF). Normally, the CF will close around the optic nerve and hyaloid vasculature. If this process does not occur properly it results in a keyhole opening in the eye known as coloboma. This results in blindness and affects nearly 1 in 4-5,000 births. Zebrafish were utilized as a model for eye development to study CF closure (CFC) …
Does Population Density Affect The Singing Behavior Of Female Canyon Wrens (Catherpes Mexicanus)?, Lorraine Dargis
Does Population Density Affect The Singing Behavior Of Female Canyon Wrens (Catherpes Mexicanus)?, Lorraine Dargis
Master's Theses
Bird song has historically been considered from the perspective of temperate males despite females in many bird species being prolific singers. In this study, I investigated one species with female song, the canyon wren (Catherpes mexicanus). Canyon wrens do not duet like many other species with female song or other wrens. Instead, males and females sing sex-specific songs. The resource defense function of male canyon wren song is well-described, and males sing often during the breeding season. Females have only been observed to sing sporadically during the breeding season but sing reliably and often when exposed to playback of other …
Type 3 T Helper Cell And Myeloid Derived Suppressor Cell Population Dynamics In A Mammary Carcinoma Model, Viva Rase
Master's Theses
Immunotherapies that augment Type I immunity show robust responses in diffuse blood cancers yet remain relatively ineffective in breast and other solid tumor malignancies. Breast tumor resistance to immunotherapies is associated with polarization towards pro-tumor Type 2 immunity, as well as the expansion of a myeloid derived suppressor cell (MDSC) population that inhibits Type 1 T helper (Th) and CD8+ cytotoxic T cells. Does polarization toward Type 3 immunity play a role in mammary tumor formation? This question had not been investigated prior to these studies despite established relationships between MDSCs and Type 3 Th cells in other inflammatory pathologies. …