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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Analyzing vertebrate movement in and around natural areas through road surveys

Freter, Victoria K. 12 August 2020 (has links)
No description available.
82

Marine Vertebrate Communities from the Cisuralian Epoch (Permian Period) of central North America

Shell, Ryan C. January 2020 (has links)
No description available.
83

Deltalike3 acts in cis to promote trans-activation of the Notch pathway in a glycosylation-dependent manner in Mus musculus and Gallus gallus models of vertebrate segmentation

Servello, Dustin Jay 12 September 2022 (has links)
No description available.
84

Vertebrate Assemblages of the Skelley Limestone (Conemaugh Group: Carboniferous, Gzhelian) in Noble and Muskingum Counties, Ohio

Cline, Daniel Austin 30 August 2022 (has links)
No description available.
85

Wnt5a Signaling Independently of the Planar Cell Polarity Pathway Resulting in Convergent Extension and Neural Tube Closure During Vertebrate Development

Barrott, Jared James 14 August 2008 (has links) (PDF)
Vertebrate development is regulated by cellular communication by mechanisms of cell fate and cell behavior. These crucial mechanisms are regulated by cellular signaling and in the case of cell fate, cellular signaling results in transcription of developmentally important genes. Communication between cells can also result in regulation of cell behavior by acting on cytoskeletal elements rather than nuclear factors. One of the cellular signals that regulate both cell fate and cell behavior is the family of Wnt signaling molecules. Wnt5a is one of 19 Wnt molecules and has been previously demonstrated to play critical roles in many important processes in embryonic development as well tumor suppression. Despite many studies that lend credence to a pathway that regulates cell behavior for Wnt5a rather than cell fate, the identity of the pathway(s) Wnt5a impinges upon remains unclear. Despite the possibility of Wnt5a signaling through multiple pathways, here, focus is given to the non-canonical Wnt signaling pathway, a pathway that regulates cell behavior, also known as the Wnt/Planar Cell Polarity (PCP) pathway. The involvement of Wnt5a in the Wnt/PCP pathway was demonstrated with a genetic approach: crossing Wnt5a heterozygous mice with mice heterozygous for a component of the Wnt/PCP pathway to uncover genetic interactions in vivo. Hence, Wnt5a X Looptail (Lp) (Wnt/PCP) heterozygous crosses have been performed. Double heterozygotes for this intercross did not exhibit a decrease in viable progeny as compared to the decreased numbers of Lp heterozygotes. These observations demonstrated a lack of genetic interaction between Wnt5a and the PCP pathway. Wnt5a mutants possess phenotypes associated with deficits in the Wnt/PCP pathway, namely convergent extension (CE) defects and neural tube closure defects. However, upon further investigation of the increased penetrance of craniorachischisis in Wnt5a-/-;Lp+/-, Wnt5a mutants do not display the characteristic broadening of the neural floor plate commonly associated with Lp-/-. This supports that Wnt5a and PCP signaling are parallel pathways that have converged to regulate different aspects of CE and neural tube closure. Despite the complexity of Wnt5a and its potential involvement in multiple pathways, dissection of this will explain the broad range of phenotypes observed.
86

Michael Rohde Thesis.pdf

Michael L Rohde (15354475) 27 April 2023 (has links)
<p>  </p> <p>Many species of turtle are facing serious declines from multiple anthropogenic causes. One such turtle native to the United States, the Blanding’s Turtle (<em>Emydoidea blandingii</em>), has faced declines in nearly every sector of their range, yet few populations have known recorded demographics, such as abundance, density, sex ratio, and body sizes. To inform managers of these crucial demographic measures of three spatially adjacent populations on Camp Grayling, MI, I implemented a capture-mark-recapture study from 2021 to 2022. I calculated Lincoln-Petersen Index and ran constant, time-varying, and behavioral response models for both full and conditional likelihoods in Program MARK. All best fit models estimated populations ≥30. The three populations sampled at Camp Grayling were low in abundance, densities, and biomass compared to some more well-known populations. Adult body weight means were 1456 g and 1223 g for males and females, respectively. Mean carapace lengths for males was 22.42 cm and females were 20.11 cm. The males of these populations were significantly larger than the mean found across the Blanding’ Turtles range. There is evidence of recruitment within these populations. A long-term research plan should be implemented and focus on investigating connectedness of these populations, as well as building data for population viability analyses. Additionally, immediate conservation action should take place to protect this vulnerable species.</p>
87

Utilization of Blow Flies (Phormia regina) as Vertebrate Resource Diversity Indicators

Ashton Brooke Jones (13150290) 08 September 2022 (has links)
<p>  </p> <p>Blow flies are often utilized in the field of forensic science due to their ability to aid in the estimation of time since death. Currently, estimations of postmortem interval require assumptions to be made and are prone to a margin of error, prompting research that may contribute to more accurate postmortem interval estimations and help to fill in the gaps of unknown information. Blow flies are necrophagous, feeding on feces and carrion, and therefore, are constantly sampling the environment. This behavior can be exploited in order to monitor the biodiversity in an environment. Through analysis of DNA isolated from the guts of blow flies, information can be obtained regarding what animals have died in an environment, what animals are still living in that environment, and the abundance and diversity of the animals present in a specific environment. Using fly-derived ingested DNA is a viable method for vertebrate resource identification and biodiversity monitoring. Over the course of a two-summer sampling period, in and around two national parks, a total of 162 blow fly (<em>Phormia regina</em>) samples returned a positive vertebrate DNA identification, with 33 species identified from five animal orders. Of the total number of flies collected and analyzed, 23.58% returned a positive vertebrate species identification. The method detected both abundant and common species based on National Park surveys, as well as some uncommon or unknown to the park species. In the SE region, 9 individuals belonging to the Rodentia order, 12 individuals belonging to the Artiodactyla order, 21 individuals belonging to the Carnivora order, 1 individual belonging to the Cingulata order, and 3 individuals belonging to the Lagomorph order were detected. In the SE region, 63% of the individuals detected belonged to the common category, 14% of the individuals detected belonged to the uncommon category, and 23% of the individuals detected belonged to the not in park/unknown category. In the NW region, 42 individuals belonging to the Rodentia order, 46 individuals belonging to the Artiodactyla order, and 28 individuals belonging to the Carnivora order were detected. In the NW region, 52% of the individuals detected belonged to the abundant category, 36% of the individuals detected belonged to the common category, and 12% of the individuals detected belonged to the uncommon category. The relative biodiversity of the sampled environment can be inferred. In the SE region, the Shannon Biodiversity Index was calculated to be 2.28 with an evenness of 0.844, while in the NW region, the Shannon Biodiversity Index was calculated to be 2.79 with an evenness of 0.855. Unsurprisingly, there was greater biodiversity in the Northwest Park samples than in the Southeast Park samples. Additionally, the ideal weather conditions for blow fly collection were determined be at a temperature of between 60- and 80-degrees Fahrenheit, a relative humidity between 50% and 60%, no precipitation, and a wind speed between 2 and 8 miles per hour. This information has further implications in the field of forensic science, specifically dealing with wildlife forensics, pathogen distributions, and can help to improve accuracy in regards to postmortem interval (PMI) estimations. </p> <p>  </p>
88

INSIGHTS INTO THE ECOLOGY OF VESPERTILIONIDAE THORUGH SKULL MORPHOLOGY AND ROOST SELECTION

Matthew S Dunn (17552733) 08 December 2023 (has links)
<p dir="ltr">Bat population numbers are declining in the Midwestern United States. Reasons for decline are multifaceted (habitat degradation, fatalities at wind turbines, White Nose Syndrome, and declining insect populations), and many species are listed as endangered (Myotis sodalis, Myotis septentrionalis, Perimyotis subflavus). Other species in the Midwestern United States have no conservation status (Eptesicus fuscus), or are only listed as a species of concern (Lasiurus cinereus, Lasiurus borealis, Lasionycteris noctivagans). Bats play a crucial role in our ecosystems, providing both ecological and economic benefit as pollinators and insect population regulators. Thus, conserving these species is vital. To gain better insight into the ecology of Midwestern bat species I studied five species in two respects. First, I investigated the availability of roosts for a colony of endangered Myotis sodalis near Indianapolis. This colony has withstood high levels of urbanization and habitat degradation. Therefore, understanding what aspects of the roosting area has allowed for continued use by the colony is crucial for future conservation efforts. I used an Akaike’s Information Criteria approach to rank models that best differentiate between the current roosting area and surrounding landscape. I identified that the roosting area contained a greater number of large standing dead trees (Snags >42.6 cm) that are able to serve as primary roosts for the colony. These results demonstrate that a colony of Indiana bats may be able to withstand urbanization if they have enough large DBH snags available in the area. Future conservation efforts in a heavily urbanized environment should focus on the maintaining large snags as primary roosts. Second, I studied the morphological variation of four species (Lasiurus cinereus, Lasiurus borealis, Lasionycteris noctivagans, and Eptesicus fuscus) to parse out differences that may lead to niche specialization. These four species share habitat and foraging range and therefore may directly compete for resources. However, despite declining insect populations these four species have moderately stable populations. I collected approximately 30 craniums and mandibles for each species and compared the linear size differences between landmarks and the overall shape variation from these landmarks. Due to different phylogenies and body sizes, the four species were different from one another in all 24 linear measurements. In regards to shape variation, the Eptesicini bat craniums had characteristics of more gracile species. In addition, the mandibles of Eptesicini were highly distinct. Lasionycteris noctivagans was the least durable and Eptesicus fuscus had 10 specialization for hard bodied prey consumption. These results suggest potential niche specialization due variation in morphology.</p>
89

Potential of selected natural products as repellents against vertebrate pests of crops

Tilly Gaoh, Abdouramane. January 1999 (has links)
No description available.
90

Regulation of glial cell development and axonal outgrowth in the vertebrate central nervous system

Zhang, Hong January 1993 (has links)
No description available.

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