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Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton Jan 2021

Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton

Graduate Research Theses & Dissertations

Madagascar has many species of extinct megafauna, including up to three species of extinct hippopotamus. Subfossil hippo specimens have been found at sites across Madagascar, yet the number of species and taxonomic relationships of the extinct Malagasy pygmy hippopotamus are poorly understood. This thesis will analyze cranial and postcranial bones to improve our understanding of the diversity and taxonomy of Malagasy subfossil hippos, focusing on adults from Ampasambazimba and Tsaramody and juveniles from Ampasambazimba and Anjohibe. Measurements of the tibia and femur of adult specimens, which are used as diagnostic features in other studies, may not be accurate diagnostic features, …

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Feeding Habits Of The Non-Native Mayan Cichlid, Mayaheros Urophthalmus, In Estuarine Tributaries Of Southwest Florida, Copley H. Smoak, Jeffrey R. Schmid Jan 2021

Feeding Habits Of The Non-Native Mayan Cichlid, Mayaheros Urophthalmus, In Estuarine Tributaries Of Southwest Florida, Copley H. Smoak, Jeffrey R. Schmid

Gulf and Caribbean Research

Foraging habits of the non—native Mayan Cichlid (Mayaheros urophthalmus) were investigated in the tidal tributaries to the Estero Bay and Wiggins Pass estuaries in southwest Florida (USA) during 2011—2013. Dietary analysis was conducted by identifying contents in the digestive tracts of 747 fish and volumetrically measuring the food items. Detritus was the predominant food item by frequency (97–100%), volume (34–48%), and alimentary importance index (47–64%). Bivalves, gastropods, decapod and cirriped crustaceans, coleopterans, serpulid polychaetes, and fish scales frequently (>50%) occurred in samples but volume and importance differed among tributaries. Results indicate that the Mayan Cichlid in southwest Florida tidal …

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Proximal And Distal Effects Of Genetic Susceptibility To Multiple Sclerosis On The T Cell Epigenome, Tina Roostaei, Hans-Ulrich Klein, Yiyi Ma, Daniel Felsky, Pia Kivisäkk, Sarah M. Connor, Alexandra Kroshilina, Christina Yung, Belinda J. Kaskow, Xiaorong Shao, Brooke Rhead, José M. Ordovás, Devin M. Absher, Donna K. Arnett, Jia Liu, Nikolaos Patsopoulos, Lisa F. Barcellos, Howard L. Weiner, Philip L. De Jager Jan 2021

Proximal And Distal Effects Of Genetic Susceptibility To Multiple Sclerosis On The T Cell Epigenome, Tina Roostaei, Hans-Ulrich Klein, Yiyi Ma, Daniel Felsky, Pia Kivisäkk, Sarah M. Connor, Alexandra Kroshilina, Christina Yung, Belinda J. Kaskow, Xiaorong Shao, Brooke Rhead, José M. Ordovás, Devin M. Absher, Donna K. Arnett, Jia Liu, Nikolaos Patsopoulos, Lisa F. Barcellos, Howard L. Weiner, Philip L. De Jager

Advanced Science Research Center

Identifying the effects of genetic variation on the epigenome in disease-relevant cell types can help advance our understanding of the first molecular contributions of genetic susceptibility to disease onset. Here, we establish a genome-wide map of DNA methylation quantitative trait loci in CD4+ T-cells isolated from multiple sclerosis patients. Utilizing this map in a colocalization analysis, we identify 19 loci where the same haplotype drives both multiple sclerosis susceptibility and local DNA methylation. We also identify two distant methylation effects of multiple sclerosis susceptibility loci: a chromosome 16 locus affects PRDM8 methylation (a chromosome 4 region not previously associated …

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Elucidation Of Multi-Origin Inula Helenium L. For Antimicrobial Activity And Heavy Metal Profiling As An Exemplar For The Use And Regulation Of Plants As Antibiotics., Ciara Ruth Kenny Jan 2021

Elucidation Of Multi-Origin Inula Helenium L. For Antimicrobial Activity And Heavy Metal Profiling As An Exemplar For The Use And Regulation Of Plants As Antibiotics., Ciara Ruth Kenny

Theses

An impending post-antibiotic era looms, thus new sources of therapeutic chemical entities are crucial to sustain effective antimicrobial chemotherapy worldwide. Plant natural products are a source of accessible, structurally diverse compounds that provide therapeutic potential. The pharmacological applications of plants in medicine can be guided by the attestation of traditional use or the application of this knowledge to uncover new leads in the drug discovery process. The range of modified in vitro methods commonly used to investigate preclinical antimicrobial efficacy of plant-derived natural products, and the associated limitations and challenges in the provision of new antimicrobial drugs from plants is …

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Initial And Advanced Stages Of Microbiota Establishment Within The Tsetse Fly, Miguel Eduardo Medina Munoz Jan 2021

Initial And Advanced Stages Of Microbiota Establishment Within The Tsetse Fly, Miguel Eduardo Medina Munoz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Symbiosis is a long-term physical association between two or more species, although little is known regarding its evolutionary origins, particularly at the genetic level. Tsetse flies are the vector of African trypanosomes, causative agents of Human and Animal African Trypanosomiases. Tsetse provide an ideal model for studying initial and advanced stages of symbiosis. Tsetse have a simple digestive tract microbiota primarily consisting of two bacteria; the ancient mutualist Wigglesworthia glossinidia and the recently acquired Sodalis glossinidius. This work presents a chronological study in evolutionary terms of the history of a microbial-insect association. First, I present concepts on symbiosis and …

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Mitochondrial Regulation Of Diabetic Kidney Disease, Daniel L Galvan, Koki Mise, Farhad R Danesh Jan 2021

Mitochondrial Regulation Of Diabetic Kidney Disease, Daniel L Galvan, Koki Mise, Farhad R Danesh

Faculty, Staff and Students Publications

The role and nature of mitochondrial dysfunction in diabetic kidney disease (DKD) has been extensively studied. Yet, the molecular drivers of mitochondrial remodeling in DKD are poorly understood. Diabetic kidney cells exhibit a cascade of mitochondrial dysfunction ranging from changes in mitochondrial morphology to significant alterations in mitochondrial biogenesis, biosynthetic, bioenergetics and production of reactive oxygen species (ROS). How these changes individually or in aggregate contribute to progression of DKD remain to be fully elucidated. Nevertheless, because of the remarkable progress in our basic understanding of the role of mitochondrial biology and its dysfunction in DKD, there is great excitement …

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Long Noncoding Rnas And Their Therapeutic Promise In Diabetic Nephropathy, Juan D Coellar, Jianyin Long, Farhad R Danesh Jan 2021

Long Noncoding Rnas And Their Therapeutic Promise In Diabetic Nephropathy, Juan D Coellar, Jianyin Long, Farhad R Danesh

Faculty, Staff and Students Publications

Recent advances in large-scale RNA sequencing and genome-wide profiling projects have unraveled a heterogeneous group of RNAs, collectively known as long noncoding RNAs (lncRNAs), which play central roles in many diverse biological processes. Importantly, an association between aberrant expression of lncRNAs and diverse human pathologies has been reported, including in a variety of kidney diseases. These observations have raised the possibility that lncRNAs may represent unexploited potential therapeutic targets for kidney diseases. Several important questions regarding the functionality of lncRNAs and their impact in kidney diseases, however, remain to be carefully addressed. Here, we provide an overview of the main …

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The E3 Ligase Traf4 Promotes Igf Signaling By Mediating Atypical Ubiquitination Of Irs-1, Wenjuan Yu, Ramesh Singh, Zhao Wang, Bert W O'Malley, Ping Yi Jan 2021

The E3 Ligase Traf4 Promotes Igf Signaling By Mediating Atypical Ubiquitination Of Irs-1, Wenjuan Yu, Ramesh Singh, Zhao Wang, Bert W O'Malley, Ping Yi

Faculty, Staff and Students Publications

Insulin-like growth factor (IGF) is a potent mitogen that activates the IGF receptor (IGFR)/insulin receptor substrate (IRS) axis, thus stimulating growth in normal cells and uncontrolled cell proliferation in cancer. Posttranslational modifications of IRS such as ubiquitination tightly control IGF signaling, and we previously identified IRS-1 as a potential substrate for the E3 ubiquitin ligase TRAF4 using an unbiased screen. Here we provide evidence that TRAF4-mediated ubiquitination of IRS-1 is physiologically relevant and crucial for IGF signal transduction. Through site-directed mutagenesis we found that TRAF4 promotes an atypical K29-linked ubiquitination at the C-terminal end of IRS-1. Its depletion abolishes AKT …

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Factors Driving The Compositional Diversity Of Apis Mellifera Bee Venom From A Corymbia Calophylla (Marri) Ecosystem, Southwestern Australia, Daniela Scaccabarozzi, Kenneth Dods, Thao T. Le, Joel P. A. Gummer, Michele Lussu, Lynne Milne, Tristan Campbell, Ben Pan Wafujian, Colin Priddis Jan 2021

Factors Driving The Compositional Diversity Of Apis Mellifera Bee Venom From A Corymbia Calophylla (Marri) Ecosystem, Southwestern Australia, Daniela Scaccabarozzi, Kenneth Dods, Thao T. Le, Joel P. A. Gummer, Michele Lussu, Lynne Milne, Tristan Campbell, Ben Pan Wafujian, Colin Priddis

Research outputs 2014 to 2021

Bee venom (BV) is the most valuable product harvested from honeybees ($30 - $300 USD per gram) but marginally produced in apiculture. Though widely studied and used in alternative medicine, recent efforts in BV research have focused on its therapeutic and cosmetic applications, for the treatment of degenerative and infectious diseases. The protein and peptide composition of BV is integral to its bioactivity, yet little research has investigated the ecological factors influencing the qualitative and quantitative variations in the BV composition. Bee venom from Apis mellifera ligustica (Apidae), collected over one flowering season of Corymbia calophylla (Myrtaceae; marri) was characterized …

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Molecular Studies On The Interactions Between Biomphalaria Snails And Schistosoma Mansoni, Lijun Lu Dec 2020

Molecular Studies On The Interactions Between Biomphalaria Snails And Schistosoma Mansoni, Lijun Lu

Biology ETDs

Biomphalaria snails serve as vectors for Schistosoma mansoni, a trematode causing human schistosomiasis. Control of Schistosoma mansoni involves chemotherapy of affected people, but new control methods built on improved understanding of schistosome-snail interactions are needed. My dissertation applies molecular and bioinformatics approaches to understand such interactions. Chapter 1 shows that significant differences exist among Biomphalaria species in Africa with respect to their ability to support schistosome development. Chapters 2 and 3 reveal the transcriptional responses of Biomphalaria glabrata susceptible (SUS) or resistant (RES) to Schistosoma mansoni. Chapter 2 identifies a new family of snail immune factors, the AIG …

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Effects Of Covid-19 On Education In Healthcare And Stem, Jessica Hallett, Santanu De Dec 2020

Effects Of Covid-19 On Education In Healthcare And Stem, Jessica Hallett, Santanu De

Biology Faculty Articles

The Coronavirus Infectious Disease 2019 (COVID-19) pandemic halted face-to-face classes in most schools, colleges, and universities worldwide, necessitating virtual instruction. This reformation of academics impacted every field of study, especially those students in the areas of Science, Technology, Engineering, and Mathematics (STEM), and in the realm of healthcare science education. Ranging from middle/high school to undergraduate and graduate programs, STEM degrees entail rigorous curricula integrating extensive lectures on theoretical topics, and laboratory exercises to apply those concepts in a practical setting. Likewise, healthcare education involves hands-on, clinical lab components working on patients, guided by supervisors. The guidelines developed by the …

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Fruiting Body Form, Not Nutritional Mode, Is The Major Driver Of Diversification In Mushroom-Forming Fungi, Marisol Sánchez-García, Martin Ryberg, Faheema Kalsoom Khan, Torda Varga, László G. Nagy, David S. Hibbett Dec 2020

Fruiting Body Form, Not Nutritional Mode, Is The Major Driver Of Diversification In Mushroom-Forming Fungi, Marisol Sánchez-García, Martin Ryberg, Faheema Kalsoom Khan, Torda Varga, László G. Nagy, David S. Hibbett

Biology

With ∼36,000 described species, Agaricomycetes are among the most successful groups of Fungi. Agaricomycetes display great diversity in fruiting body forms and nutritional modes. Most have pileate-stipitate fruiting bodies (with a cap and stalk), but the group also contains crust-like resupinate fungi, polypores, coral fungi, and gasteroid forms (e.g., puffballs and stinkhorns). Some Agaricomycetes enter into ectomycorrhizal symbioses with plants, while others are decayers (saprotrophs) or pathogens. We constructed a megaphylogeny of 8,400 species and used it to test the following five hypotheses regarding the evolution of morphological and ecological traits in Agaricomycetes and their impact on diversification: 1) resupinate …

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Temporal Thermal Heterogeneity As A Potential Evolutionary Driver Of Thermoregulation In The Generalist Grasshopper Melanoplus Differentialis From Five Sites In The Midwestern And Southern United States, Devin Preston Dec 2020

Temporal Thermal Heterogeneity As A Potential Evolutionary Driver Of Thermoregulation In The Generalist Grasshopper Melanoplus Differentialis From Five Sites In The Midwestern And Southern United States, Devin Preston

LSU New Orleans Theses and Dissertations

Environmental drivers of the evolution of thermoregulation, especially thermal fluctuation, have been incompletely investigated. I used a combination of field and laboratory studies to determine if thermal heterogeneity selected for greater thermal tolerance or ability to thermoregulate in a generalist grasshopper by testing upper and lower thermal limits, behavioral thermoregulation, and acclimation. I measured these from individuals originating from sites that had varying degrees of thermal fluctuation over time. I found partial support for thermal heterogeneity as an evolutionary driver of thermal tolerance, behavioral thermoregulation, and acclimation. However, whether or not differences in these metrics conformed to my hypothesis varied …

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Comparison Of Cardiac Muscle Between Male And Female Rats With Exercise And Aging: Analyzing Vitals, Gdnf Expression, Ngf Expression, Rna Expression, Sympathetic Innervation, Parasympathetic Innervation, And Sensory Innervation, Katelyn Kurrie Dec 2020

Comparison Of Cardiac Muscle Between Male And Female Rats With Exercise And Aging: Analyzing Vitals, Gdnf Expression, Ngf Expression, Rna Expression, Sympathetic Innervation, Parasympathetic Innervation, And Sensory Innervation, Katelyn Kurrie

Honors Theses

The direction of my research-based thesis answers the question of how exercise affects the cardiovascular system with aging in male and female rats. My study would highlight the important differences of the cardiovascular system of both sexes which could lead to sex-specific insight on the cardiovascular disease epidemic which prevails as the most common cause of death in the United States. The studies completed will test the hypothesis: neurotrophic factor will be higher in females than males due to the higher presence of estrogen in females. The trophic factor is predicted to increase in both males and females with regular …

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The Genetic Influence On Subjective Well-Being: A Review Of The Current Knowledge On The Role Of Genetics On Our Sense Of Subjective Well-Being And The Implications It Has For Future Research In Improving Well-Being At Both A Population And Individual Level., Abhishek Gupta Dec 2020

The Genetic Influence On Subjective Well-Being: A Review Of The Current Knowledge On The Role Of Genetics On Our Sense Of Subjective Well-Being And The Implications It Has For Future Research In Improving Well-Being At Both A Population And Individual Level., Abhishek Gupta

Honors Scholar Theses

This thesis project explores the genetic underpinnings of one of the most cherished attributes in the world, well-being.1 Specifically, it attempts to understand the influence of the genome on subjective, or experienced, well-being. An investigation was conducted into current literature concerning both the structure of measurement devices of well-being as well as association studies to determine the scope of the correlation that exists between the genome and well-being and identify genetic findings of interest. Ultimately, being able to provide evidence of causality between the genome and sense of well-being at this iteration of well-being and genome research is limited, …

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Innate Pathogenic Traits In Oral Yeasts, Ayat Ibrahiem Esmaeel Al-Laaeiby, Adnan A. Al-Mousawi, Inaam M.N. Alrubayae, Abdullah Al-Saadoon, Maysoon Almayahi Dec 2020

Innate Pathogenic Traits In Oral Yeasts, Ayat Ibrahiem Esmaeel Al-Laaeiby, Adnan A. Al-Mousawi, Inaam M.N. Alrubayae, Abdullah Al-Saadoon, Maysoon Almayahi

Karbala International Journal of Modern Science

The normal flora community plays a significant role in both healthy and patient individual’s bodies. It has improved its ability to change from beneficial to opportunistic organisms causing crucial infections in immunocompromised patients. This study was conducted to identify the community of yeast species, and to investigate potential virulence factors. Saliva samples were collected from healthy individuals, yeast species were isolated and identified using both traditional and advance molecular genetics technique. The results revealed that Candida albicans was the dominant isolate, while Meyerozyma caribbica was the least. The phylogenetic tree was constructed for 13 species using the Neighbour-Joining method, which …

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Maize Microrna166 Inactivation Confers Plant Development And Abiotic Stress Resistance, Na Li, Tianxiao Yang, Zhanyong Guo, Qiusheng Wang, Mao Chai, Mingbo Wu, Xiaoqi Li, Weiya Li, Guangxian Li, Jihua Tang, Guiliang Tang Dec 2020

Maize Microrna166 Inactivation Confers Plant Development And Abiotic Stress Resistance, Na Li, Tianxiao Yang, Zhanyong Guo, Qiusheng Wang, Mao Chai, Mingbo Wu, Xiaoqi Li, Weiya Li, Guangxian Li, Jihua Tang, Guiliang Tang

Michigan Tech Publications, Part 1

MicroRNAs are important regulators in plant developmental processes and stress responses. In this study, we generated a series of maize STTM166 transgenic plants. Knock-down of miR166 resulted in various morphological changes, including rolled leaves, enhanced abiotic stress resistance, inferior yield-related traits, vascular pattern and epidermis structures, tassel architecture, as well as abscisic acid (ABA) level elevation and indole acetic acid (IAA) level reduction in maize. To profile miR166 regulated genes, we performed RNA-seq and qRT-PCR analysis. A total of 178 differentially expressed genes (DEGs) were identified, including 118 up-regulated and 60 down-regulated genes. These DEGs were strongly enriched in cell …

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Assessing Moringa Oleifera Plants As Exposure Pathways For Heavy Metals In Highly Contaminated Areas, Marissa Louise Mayfield* Dec 2020

Assessing Moringa Oleifera Plants As Exposure Pathways For Heavy Metals In Highly Contaminated Areas, Marissa Louise Mayfield*

Biology Theses

This study examined the uptake of heavy metals by Moringa oleifera trees in both field and laboratory settings. The main goal of this study was to determine whether using Moringa, grown in heavily contaminated areas, as food or herbal supplements increases the risk of heavy metal exposure. The field component of this study was carried out in the Southern part of Kabwe, Zambia where a lead-zinc mine has left a legacy of severe environmental pollution in the neighboring areas. Moringa trees have several medicinal properties which is one of the reasons they were first introduced to the area. The trees …

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The Use Of Bacteriophages For Food Safety, Lorraine Endersen, Aidan Coffey Dec 2020

The Use Of Bacteriophages For Food Safety, Lorraine Endersen, Aidan Coffey

Department of Biological Sciences Publications

The search for natural biocontrol agents that allow the production of foods that are safe for human consumption and do not impact the taste, texture, and nutritional quality of the food, is a constant challenge for diverse food industries worldwide, particularly as the human population continues to rise globally, and multiple antibiotic resistance in pathogenic bacteria is increasingly prevalent. Bacteriophages (phages), the naturally occurring predators of bacteria, are harmless to humans and animals and are ubiquitous in the environment — and as such, have been recognised as promising antimicrobial agents to help control specific bacterial pathogens in food production. This …

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Harvester Ants Reduce Seed Survivorship In Slickspot Peppergrass, A Rare Mustard Endemic To Idaho, Jennifer A. Brown, Ian C. Robertson Dec 2020

Harvester Ants Reduce Seed Survivorship In Slickspot Peppergrass, A Rare Mustard Endemic To Idaho, Jennifer A. Brown, Ian C. Robertson

Biology Faculty Publications and Presentations

Seed predation can significantly reduce the reproductive success of individual plants and their populations. The consequences of seed predation often are most pronounced for rare plant species, in which loss of seeds can have a disproportionate effect on populations. The present study examined the effects of seed predation by Owyhee harvester ants (Pogonomyrmex salinus) on seed survivorship in slickspot peppergrass (Lepidium papilliferum), a rare mustard endemic to sagebrush-steppe habitat in southwestern Idaho. Within sagebrush-steppe, L. papilliferum is restricted to microsites known as “slick spots”—shallow depressions of soil characterized by distinct clay layers and surface water retention …

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Pathology Findings And Correlation With Body Condition Index In Stranded Killer Whales (Orcinus Orca) In The Northeastern Pacific And Hawaii From 2004 To 2013, Stephen A. Raverty, Judy St. Leger, Dawn P. Noren, Kathy Burek Huntington, David S. Rotstein, Francis M.D. Gulland,, Deborah A. Duffield, Multiple Additional Authors Dec 2020

Pathology Findings And Correlation With Body Condition Index In Stranded Killer Whales (Orcinus Orca) In The Northeastern Pacific And Hawaii From 2004 To 2013, Stephen A. Raverty, Judy St. Leger, Dawn P. Noren, Kathy Burek Huntington, David S. Rotstein, Francis M.D. Gulland,, Deborah A. Duffield, Multiple Additional Authors

Biology Faculty Publications and Presentations

Understanding health and mortality in killer whales (Orcinus orca) is crucial for management and conservation actions. We reviewed pathology reports from 53 animals that stranded in the eastern Pacific Ocean and Hawaii between 2004 and 2013 and used data from 35 animals that stranded from 2001 to 2017 to assess association with morphometrics, blubber thickness, body condition and cause of death. Of the 53 cases, cause of death was determined for 22 (42%) and nine additional animals demonstrated findings of significant importance for population health. Causes of calf mortalities included infectious disease, nutritional, and congenital malformations. Mortalities in sub-adults were …

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Hormonal Responses To Seasonal Thermal And Ecological Stressors In Japanese Macaques (Macaca Fuscata), Lilianne Nelson Dec 2020

Hormonal Responses To Seasonal Thermal And Ecological Stressors In Japanese Macaques (Macaca Fuscata), Lilianne Nelson

Masters Theses

Relative to most primate species, Japanese macaques (Macaca fuscata) experience extreme seasonal variation in thermal and ecological stressors that can impact energetic demands. To cope with these environmental changes, levels of metabolic hormones, such as cortisol and triiodothyronine, fluctuate to facilitate energetic adjustments. While previous research in primates has investigated thermal and ecological stressors individually, a combined assessment of these stressors alongside hormone levels can provide a more holistic understanding of the relationship between a primate’s thermoregulation, energetic balance, and stress. The goals of this study were to determine the effects of season, temperature and ecological stress on …

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Drivers Of Decadal Vegetation Change In Northern Alaska, Jacob Allen Harris Dec 2020

Drivers Of Decadal Vegetation Change In Northern Alaska, Jacob Allen Harris

Masters Theses

The Arctic is experiencing rapid climate change. This research documents vegetation change near Atqasuk and Utqiaġvik, Alaska. At each location, 30 plots distributed in a matrix across the landscape, were sampled annually from 2010 to 2019 using a point frame. For every encounter we recorded the height and classified it into eight broad functional groups (deciduous shrubs, evergreen shrubs, forbs, graminoids, bryophytes, lichens, litter and standing dead vegetation); for vascular plants we also identified the species. We found a consistent increase in plant stature and cover over time which was dramatic at Atqasuk. Graminoid cover and height increased at both …

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Lianas Maintain Insectivorous Bird Abundance And Diversity In A Neotropical Forest, Stefan A. Schnitzer, Nicole L. Michel, Jennifer S. Powers, W. Douglas Robinson Dec 2020

Lianas Maintain Insectivorous Bird Abundance And Diversity In A Neotropical Forest, Stefan A. Schnitzer, Nicole L. Michel, Jennifer S. Powers, W. Douglas Robinson

Biological Sciences Faculty Research and Publications

The spatial habitat heterogeneity hypothesis posits that habitat complexity increases the abundance and diversity of species. In tropical forests, lianas add substantial habitat heterogeneity and complexity throughout the vertical forest profile, which may maintain animal abundance and diversity. The effects of lianas on tropical animal communities, however, remain poorly understood. We propose that lianas have a positive effect on animals by enhancing habitat complexity. Lianas may have a particularly strong influence on the forest bird community, providing nesting substrate, protection from predators, and nutrition (food). Understory insectivorous birds, which forage for insects that specialize on lianas, may particularly benefit. Alternatively, …

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Tissue-Specific Responses From A Global Developmental Signal: A Detailed Subcellular Analysis Of The 20e And Rab Signaling Pathways Controlling Exocrine Secretion During Drosophila Development, Nichalas Nelson Dec 2020

Tissue-Specific Responses From A Global Developmental Signal: A Detailed Subcellular Analysis Of The 20e And Rab Signaling Pathways Controlling Exocrine Secretion During Drosophila Development, Nichalas Nelson

UNLV Theses, Dissertations, Professional Papers, and Capstones

During metamorphosis, the steroid hormone 20-hydroxecydysone (20E) triggers a plethora of tissue-specific responses in the common fruit fly, Drosophila melanogaster. The salivary glands are exocrine organs that respond to a large pulse of 20E to secrete a massive cargo of stored glycoproteins called glue. Because the glands are amenable to ex vivo-organ culture and powerful genetic manipulations, they are an excellent model for studying the conserved developmental and physiological signaling pathways that regulate the general function of these specialized secretory tissues. Our lab has generated transgenic animals in which the secreted glue molecules are tagged with fluorescent proteins. I have …

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Promoting The Sustainability Of The Gulf Of Maine Recreational Groundfish Fishery Through Discard Mortality Estimation, Mitigation, And Outreach, Connor W. Capizzano Dec 2020

Promoting The Sustainability Of The Gulf Of Maine Recreational Groundfish Fishery Through Discard Mortality Estimation, Mitigation, And Outreach, Connor W. Capizzano

Graduate Doctoral Dissertations

Recreational fishing (i.e., angling), a popular leisure activity that provides socio-economic benefits to human societies around the world, can represent a significant source of fishing mortality and impact fish populations and marine ecosystems. Although fish are often released by recreational anglers to reduce fishing mortality rates, the efficacy of discarding fish is often criticized given that fish can die from the factors experienced during the capture, handling, and release process (i.e., discard mortality). Despite this recognition, the rate at which fish suffer discard mortality in specific commercial and recreational fisheries is often unknown and difficult to obtain due to logistical …

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The Effects Of Multiple Stressors On Stream Communities: The Convergence Of Drought, Nutrient Pollution, And Invasive Species, Robert Joseph Fournier Iii Dec 2020

The Effects Of Multiple Stressors On Stream Communities: The Convergence Of Drought, Nutrient Pollution, And Invasive Species, Robert Joseph Fournier Iii

Graduate Theses and Dissertations

Freshwater systems experience multi-faceted degradation from a variety of ecological and environmental stressors. Three common stressors in these systems, drought, nutrient pollution, and invasive species, have wide-ranging effects on stream population- community- and ecosystem dynamics. We have a broad understanding of how each of these stressors works to influence stream systems independently. However, we still know relatively little about if, and how, these stressors might interact when they co-occur. Though drought is a natural part of many stream systems, all three of these stressors can be exacerbated or facilitated by anthropogenic actions. Accordingly, as human population and resource use continue …

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A Spatial And Multivariate Approach To Examining Effects Of Urbanization On Nitrogen Sources, Organic Matter Inputs, And Trophic Structure In Streams Of Cobb And Paulding Counties, Georgia., Katharine Horning Nov 2020

A Spatial And Multivariate Approach To Examining Effects Of Urbanization On Nitrogen Sources, Organic Matter Inputs, And Trophic Structure In Streams Of Cobb And Paulding Counties, Georgia., Katharine Horning

Master of Science in Integrative Biology Theses

Urbanization and land use changes have a negative effect on streams often causing numerous physical changes in stream morphology, a change in nutrient concentrations, and altered ecosystems contributing to a loss of habitat, decreased biodiversity, and loss of stability for ecosystem function (Walsh et al., 2005; Meyer et al., 2005; Cardinale and Palmer, 2012). The use of stable isotope analysis for monitoring could be valuable because it accounts for temporal integration from anthropogenic wastewater inputs, characterized by a shift in the abundance of 15N. This project had three main objectives: (1) to examine how nitrogen and carbon sources are …

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Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes Nov 2020

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …

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A Multi‑Disciplinary Comparison Of Great Ape Gut Microbiota In A Central African Forest And European Zoo, Victor Narat, Katherine R. Amato, Noémie Ranger, Maud Salmona, Séverine Mercier‑Delarue, Stephanie Rupp, Philippe Ambata, Richard Njouom, François Simon, Tamara Giles‑Vernick, Jérôme Legoff Nov 2020

A Multi‑Disciplinary Comparison Of Great Ape Gut Microbiota In A Central African Forest And European Zoo, Victor Narat, Katherine R. Amato, Noémie Ranger, Maud Salmona, Séverine Mercier‑Delarue, Stephanie Rupp, Philippe Ambata, Richard Njouom, François Simon, Tamara Giles‑Vernick, Jérôme Legoff

Publications and Research

Comparisons of mammalian gut microbiota across different environmental conditions shed light on the diversity and composition of gut bacteriome and suggest consequences for human and animal health. Gut bacteriome comparisons across different environments diverge in their results, showing no generalizable patterns linking habitat and dietary degradation with bacterial diversity. The challenge in drawing general conclusions from such studies lies in the broad terms describing diverse habitats (“wild”, “captive”, “pristine”). We conducted 16S ribosomal RNA gene sequencing to characterize intestinal microbiota of free-ranging sympatric chimpanzees and gorillas in southeastern Cameroon and sympatric chimpanzees and gorillas in a European zoo. We conducted …

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