Digital Commons Network^™

Investigating Neurogenesis As A Veritable Epigenetic Endophenotype For Alzheimer's Disease, Layne Wells

Scripps Senior Theses

Alzheimer's disease (AD) is the most common neurodegenerative disease, characterized by progressive amyloid plaque aggregation, neurofibrillary tangles, and cortical tissue death. As the prevalence of AD is projected to climb in coming years, there is a vested interest in identifying endophenotypes by which to improve diagnostics and direct clinical interventions. The risk for complex disorders, such as AD, is influenced by multiple genetic, environmental, and lifestyle factors. Significant strides have been made in identifying genetic variants linked to AD through the genome-wide association study (GWAS). It has been estimated in more recent years, however, that GWAS-identified variants account for limited …

Ectoparasite Presence In Select Northcentral Kansas Bat Species, Elizabeth Schumann

Master's Theses or Doctor of Nursing Practice

Working with other graduate students on a grant given to Fort Hays State University, from the Kansas Department of Wildlife, Parks and Tourism, I looked at presence and species of ectoparasites on bat species. The main goal of our grant was to quantify and qualify the status of the northern myotis (Myotis septentrionalis) in the state of Kansas, and to record data on any bycatch. I worked on our grant in the summer field seasons of 2016 and 2017, May to October, as described by the Indiana bat protocol.

Bats were captured by using mist nets set over …

Nutrient Flux From Aquatic To Terrestrial Invertebrate Communities Across A Lakeside Ecotone, Hosanna B. Loreaux

Browse all Theses and Dissertations

In this study, I examined how the spatiotemporal distribution of spider webs and diet changed in a lake riparian zone with increasing distance from an aquatic resource. I surveyed twenty, one-hundred meter transects along the perimeters of Sanford and Escanaba lakes (Wisconsin). Overall, spider web abundance was highest near the lakes and decreased moving into the adjacent forest. Horizontal orb webs, vertical orb webs, and mesh webs showed strong negative relationships with distance from the lakes. Aquatic insects composed an average 36-64% of spider diet for all spider families throughout the riparian zone, suggesting that some spider families are selecting …

Ribbeting Results: Emergent Infectious Diseases In Wetland Systems, Ariel Horner

Electronic Theses and Dissertations

North American amphibians have recently been impacted by two major emerging pathogens, the fungus Batrachochytrium dendrobatidis (Bd) and iridoviruses in the genus Ranavirus (Rv). Environmental, seasonal and host factors may play important roles in disease dynamics, but few studies incorporate these components into their analyses. Here, we investigated the role of environmental, seasonal, genetic and location effects on driving Bd and Rv infection prevalence and severity in a biodiversity hot spot, the southeastern United States. We used quantitative PCR to characterize Bd and Rv dynamics in natural populations of three amphibian species: Notophthalmus perstriatus, Hyla squirella and Pseudacris ornata and …

Examining Aspen Expansion From Before And After Prescribed Burning In A Native Fescue Grassland Through Geospatial Techniques, Christopher Anderson

Dissertations, Master's Theses and Master's Reports

Native fescue (Fescue spp.) grasslands of the Intermountain West have become increasingly scarce due to the advent of modern agriculture, the loss of Indigenous people’s land management practices, modern wildfire management and the extirpation of bison (Bison bison bison). Native grassland is a biodiversity hot-spot, is significant for carbon sequestration, and essential to many species of flora and fauna that occur in the ecosystem. Our study site, on the Rocky Mountain Front in Waterton Lakes National Park, Alberta Canada, consists of 30 discrete aspen stands (Populous tremuloides) which are encroaching on this declining shortgrass fescue …

Morphological And Leaf Anatomical Variability Of Crocus Cf. Heuffelianus Herb. (Iridaceae) Populations From The Different Habitats Of The Balkan Peninsula, Irena Raca, Milica Jovanovic, Irena Ljubisavljevic, Marina Juskovic, Vladimir Randelovic

Turkish Journal of Botany

Crocus cf. heuffelianus Herb. belongs to the series Verni Mathew and presents one of the most complex and critical taxa within the whole genus Crocus L. Depending on different authors, C. cf. heuffelianus is sometimes split into different taxa (e.g., C. scepusiensis (Rehmer & Wol.) Borbás ex Kulcz., C. vittatus Schloss. & Vuk., nom. illeg.). In order to disentangle the complicated taxonomical status of this species and to determine the degree of its morphoanatomical variability in the different environmental conditions, a comparative investigation of plant morphology and leaf anatomy of seven populations from the Balkan Peninsula was carried out. Morphometric …

Density And Distribution Of Piscivorous Fishes In The Sacramento – San Joaquin Delta, Christopher M. Loomis

Cal Poly Humboldt theses and projects

Predatory fishes, including numerous introduced species, are common to the Sacramento – San Joaquin Delta, but abundance data for most species is insufficient to determine the Delta-wide distribution and ecological impacts of these species. Predatory fishes (e.g. Striped Bass, Largemouth Bass have long been suspected of contributing to the decline of native species, including salmonids, but data has been insufficient to investigate this hypothesis. In this study, I present a novel method to assess predator fish populations across the southern Delta using DIDSON acoustic cameras and analyze the environmental associations that form the landscape and fine-scale distribution of predatory fishes. …

Isolation, Characterization, And Cross-Amplification Of 20 Microsatellite Markers For The Rare Conospermum Undulatum (Proteaceae), Nicola Delnevo, Andrea Piotti, Eddie J. Van Etten, William D. Stock, Margaret Byrne

Research Datasets

Premise of the study: Recent habitat fragmentation is posing a risk to the wavy-leaved smokebush, Conospermum undulatum, a rare plant species endemic to the south-western Western Australia. Microsatellites markers are required to characterize the genetic diversity and structure of the species for conservation purposes and to facilitate ecological studies. Methods and Results: Illumina MiSeq high-throughput sequencing was used to develop 20 novel microsatellite markers for C. undulatum. Polymorphism at each locus was assessed using 72 individuals from three natural populations. Nineteen markers were polymorphic, with the number of alleles per locus ranging from two to 21, and observed and expected …

Dna Methylation And Genetic Divergence Associated With An Inducible Defensive Response In Mimulus Guttatus, David Farr

All Master's Theses

Phenotypic plasticity allows many organisms to respond to their environment by changing their phenotype, but the mechanisms to do so are not well understood. Yellow Monkeyflower (formerly Mimulus guttatus; now Erythranthe guttata) is one such organism that can serve as a model to promote our understanding of these mechanisms due to its striking response to insect herbivory. Monkeyflower responds to leaf damage by increasing the number of hair-like glandular trichomes, a putative defensive trait that reduces the magnitude of damage by insects. This plastic response is transgenerationally inherited in a way that is sensitive to genome-wide demethylation when …

What Lies Beneath? : Removal Sampling To Test For Biases In Surface Activity Of The Eastern Red-Backed Salamander (Plethodon Cinereus), Amelia Tedesco

Honors Theses

In light of the current global amphibian extinction crisis from threats such as climate change and disease, reliable and repeatable sampling methods carry heavy importance for assessing North American salamander species.

Machine Learning To Classify Animal Species In Camera Trap Images: Applications In Ecology, Michael A. Tabak, Mohammad S. Norouzzadeh, David W. Wolfson, Steven J. Sweeney, Kurt C. Vercauteren, Nathan P. Snow, Joseph M. Halseth, Paul A. Di Salvo, Jesse S. Lewis, Michael D. White, Ben Teton, James C. Beasley, Peter E. Schlichting, Raoul K. Boughton, Bethany Wight, Eric S. Newkirk, Jacob S. Ivan, Eric A. Odell, Ryan K. Brook, Paul M. Lukacs, Anna K. Moeller, Elizabeth G. Mandeville, Jeff Clune, Ryan S. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

1. Motion-activated cameras (“camera traps”) are increasingly used in ecological and management studies for remotely observing wildlife and are amongst the most powerful tools for wildlife research. However, studies involving camera traps result in millions of images that need to be analysed, typically by visually observing each image, in order to extract data that can be used in ecological analyses.

2. We trained machine learning models using convolutional neural networks with the ResNet-18 architecture and 3,367,383 images to automatically classify wildlife species from camera trap images obtained from five states across the United States. We tested our model on an …

Population Demographics And Active Foraging Behavior Of Copperheads (Agkistrodon Contortrix) At A Recreational Site In Eastern Kentucky, Jocelyn Hendricks

Online Theses and Dissertations

Recreational areas represent a significant source of human-wildlife interaction, which can have an especially negative effect on organisms, like snakes, that are generally perceived as dangerous by the public. Considering the projected increase in recreation rates in the United States, the threat to this already vulnerable group of organisms deserves attention. While habitat factors associated with recreational areas—fragmentation, decreased canopy cover, altered vegetation composition—have been shown to affect snake thermoregulatory behavior and abundance, detailed studies of wild snake behavior are uncommon due to their cryptic nature. The goal of this study was to reduce human-wildlife conflict at a recreational site …

Genome Size Variation Among Natural Populations Of Brachypodium Distachyon And B. Hybridum Collected From Different Regions Of Turkey, Gülsemi̇n Savaş Tuna, İsmet Başer, Meti̇n Tuna

Turkish Journal of Botany

Brachypodium distachyon (L.) P.Beauv. is a model grass species that is useful for studying temperate cereal, forage, and energy crops. In this study we aimed to determine the genome size and species identity in the collections of the B. distachyon complex that included samples from 56 different locations in Turkey, applying chromosome counting and nuclear genome size evaluation by flow cytometry method (FCM). Moreover, the study examined whether diverse geographical conditions at the collecting sites influence the genome size. Chromosomal analysis revealed that the number of B. distachyon (x = 5, 2n = 10) genotypes was 48 and the number …

Diurnal Habitat Selection Of Migrating Whooping Crane In The Great Plains, David M. Baasch, Patrick D. Farrell, Aaron T. Pearse, David A. Brandt, Andrew J. Caven, Mary J. Harner, Greg D. Wright, Kristine L. Metzger

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Available stopover habitats with quality foraging opportunities are essential for migrating waterbirds, including Whooping Crane (Grus americana). Several studies have evaluated habitats used by Whooping Crane for roosting throughout its migration corridor; however, habitats associated with foraging and other diurnal activities have received less attention. We used data collected from 42 Whooping Crane individuals that included 2169 diurnal use locations within 395 stopover sites evaluated during spring 2013 to fall 2015 to assess diurnal habitat selection throughout the U.S. portion of the migration corridor. We found that Whooping Crane selected wetland land-cover types (i.e., open water, riverine, and semipermanent wetlands) …

Viral Emergence In Marine Mammals In The North Pacific May Be Linked To Arctic Sea Ice Reduction, Elizabeth Vanwormer, J. A.K. Mazet, A. Hall, V. A. Gill, P. L. Boveng, J. M. London, T. Gelatt, B. S. Fadely, M. E. Lander, J. Sterling, V. N. Burkanov, R. R. Ream, P. M. Brock, L. D. Rea, B. R. Smith, A. Jeffers, M. Henstock, M. J. Rehberg, K. A. Burek-Huntington, S. L. Crosby, J. A, Hammond, T. Goldstein

School of Veterinary and Biomedical Sciences: Faculty Publications

Climate change-driven alterations in Arctic environments can influence habitat availability, species distributions and interactions, and the breeding, foraging, and health of marine mammals. Phocine distemper virus (PDV), which has caused extensive mortality in Atlantic seals, was confirmed in sea otters in the North Pacific Ocean in 2004, raising the question of whether reductions in sea ice could increase contact between Arctic and sub-Arctic marine mammals and lead to viral transmission across the Arctic Ocean. Using data on PDV exposure and infection and animal movement in sympatric seal, sea lion, and sea otter species sampled in the North Pacific Ocean from …

Relationships Between Wildfire Burn Severity, Cavity-Nesting Bird Assemblages, And Habitat In An Eastern Ponderosa Pine Forest, Emma C. Keele, Victoria M. Donovan, Caleb P. Roberts, Sarah M. Nodskov, Carissa L. Wonkka, Craig R. Allen, Larkin A. Powell, David A. Wedin, David G. Angeler, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Historically, eastern ponderosa pine (Pinus ponderosa) forests were described as sparse patches of old-growth trees maintained by frequent, low-severity fires; however, in recent decades, there have been a number of large mixed-severity wildfires throughout the range of these forests. Wildlife responses to severe fire disturbance in eastern ponderosa pine forests are not well understood. Our study investigates how cavity-nesting bird species in an eastern ponderosa pine forest are impacted by burn severity. The objectives of our study were to: (1) identify the community composition of cavity-nesting birds in a 27 y old burn of mixed severity, (2) assess …

United States Midwest Soil And Weather Conditions Influence Anaerobic Potentially Mineralizable Nitrogen, Jason D. Clark, Kristen S. Veum, Fabian G. Fernandez, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A. M. Laboski, Emerson D. Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Nitrogen provided to crops through mineralization is an important factor in N management guidelines. Understanding of the interactive effects of soil and weather conditions on N mineralization needs to be improved. Relationships between anaerobic potentially mineralizable N (PMN_an) and soil and weather conditions were evaluated under the contrasting climates of eight US Midwestern states. Soil was sampled (0–30 cm) for PMN_an analysis before pre-plant N application (PP_0N) and at the V5 development stage from the pre-plant 0 (V5_0N) and 180 kg N ha−1 (V5_180N) rates and incubated for 7, 14, and …

Do Saproxylic Curculionids Affect The Fitness Of Co-Occurring Cerambycids?, Sheila R. Heath

Dissertations and Theses

Saproxylic insects sometimes coexist in incredibly high numbers under bark and share common resources. Thus, interactions between species are possible and could even explain their coexistence. This study investigates evidence of negative or positive effects of curculionid beetles (Coleoptera: Curculionidae) on cerambycid beetles (Coleoptera: Cerambycidae) that coexisted in dead tree branches in Costa Rica. Co-occurrence analysis and generalized regressions were used to test associations between cerambycid and curculionid species. Three cerambycid species that each co-occurred with a curculionid species were selected to measure fitness. Fitness measures of the cerambycid were compared with abundance of the co-occurring curculionid to assess the …

Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South

Human–Wildlife Interactions

Effective management of rodent pests requires an ecological understanding of how they move through their environment and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space, but this field is often unapproachable to non-scientist pest management professionals (PMPs). In this …

Impacts Of Plant-Microbe Interactions On Seedling Performance In A Riparian Forest Invaded By Lonicera Maackii, Taylor E. K. Strehl

Masters Theses

Soil microbes have profound impacts on plant growth and survival and can either promote or inhibit plant dominance. Exotic plants are often strongly invasive because they have escaped their natural enemies, potentially including antagonistic soil microbes. I examined how the invasive shrub Lonicera maackii and a common native tree, Acer negundo, responded to soil microbial communities to determine the role of soil microbes in regulating invasion success. This was done by growing both species with microbes from invaded (L. maackii) and uninvaded (A. negundo) soils collected from three locations within a riparian forest. Seedlings were …

Identifying Priority Conservation Areas And Strategies For Myotis Sodalis (Chiroptera: Vespertilionidae) Via Habitat And Connectivity Modeling, Ashleigh B. Cable

Masters Theses

Myotis sodalis, the Indiana bat, is a federally endangered bat species in the United States of America (USA). Conservation efforts are typically focused at identified maternity sites at local scales, however, the species is a regional migrant that interacts with its environment at multiple spatial scales. We are limited in our knowledge of landscape-level requirements of this species, especially in large areas such as Illinois, USA, where a wide range of environmental and landscape conditions exist. Many previous M. sodalis habitat studies have limited their focus to smaller spatial scales. Due to limitations in funding, personnel, and time, it …

Recent Changes In The Zooplankton Communities Of Arctic Tundra Ponds In Response To Warmer Temperatures And Nutrient Enrichment, Mariana Vargas Medrano

Open Access Theses & Dissertations

Warming is altering Arctic freshwater ecosystems, enriching the water column, increasing primary productivity and shifting the composition, dominance and the timing of emergence and reproduction of zooplankton communities. Historic data from arctic tundra ponds near UtqiaÄ¡vik, AK have given us valuable insight into changes that have occurred in recent times. A change of dominance from cyclopoid copepods to Daphnia middendorffiana has occurred over a 40 year period. Daphnia are more common, abundant and larger, which may be explained by increased primary productivity stimulated by nutrient release from permafrost thaw. Copepods and fairy shrimp emerged earlier from the overwintering states, which …

Treatment, Prevention And Public Health Management Of Impetigo, Scabies, Crusted Scabies And Fungal Skin Infections In Endemic Populations: A Systematic Review, Philippa J. May, Steven Y.C Tong, Andrew C. Steer, Bart J. Currie, Ross M. Andrews, Jonathan R. Carapetis, Asha C. Bowen

Health Sciences Papers and Journal Articles

We conducted a systematic review of the treatment, prevention and public health control of skin infections including impetigo, scabies, crusted scabies and tinea in resource-limited settings where skin infections are endemic. The aim is to inform strategies, guidelines and research to improve skin health in populations that are inequitably affected by infections of the skin and the downstream consequences of these. The systematic review is reported according to the PRISMA statement. From

1759 titles identified, 81 full text studies were reviewed and key findings outlined for impetigo, scabies, crusted scabies and tinea. Improvements in primary care and public health management …

Eternal Enemies, Or Incidental Encounters? Structure And Patterns Of Interspecific Killing In Carnivora, Tor G. Bertin

Theses and Dissertations

Lethal interactions between carnivorans (interspecific killing) may influence their population dynamics, behavior, and other important aspects of their ecology. In this study, I expand upon previous research on the broad-scale patterns of interspecific killing in Carnivora (Palomares & Caro 1999, Donadio & Buskirk 2006) with a greatly expanded dataset (inclusion of scat and stomach data and more intensive sampling of the literature), and suggest avenues for future research. While like previous studies, I found a positive effect of relative body size between killer species and killed species on the likelihood of forming a killing interaction, I failed to find evidence …

Ectomycorrhizal Fungal Community Assembly On Seedlings Of A Neotropical Monodominant Tree, Carolyn Delevich

Cal Poly Humboldt theses and projects

Formation of ectomycorrhizae may facilitate early seedling survival of ectomycorrhizal tree species due to enhanced nutrient acquisition. This could be especially important in heavily shaded understories of tropical monodominant forests where host plant photosynthetic capacity is limited. Little information is available on ectomycorrhizal (ECM) fungal colonization or community development of monodominant seedling cohorts, which have high survival rates. Following a 2016 mast seeding event, we sequentially measured percent colonization and species composition of ECM fungi on live and recently dead seedlings of the tropical monodominant tree Dicymbe corymbosa. We also compared seedling ECM fungi to those of nearby adult …

Ecological Surveys On The Parthenogenetic Artemia Populations In The Hypersaline Lakes Of Anatolia, Turkey, Armi̇n Eskandari̇, Yasemi̇n Saygi

Turkish Journal of Zoology

The objective of this study is to provide information on the parthenogenetic Artemia populations in some hypersaline lakes of Anatolia (Tuz, Bolluk, Tersakan, and Acıgöl). Sampling studies were performed for abiotic factors and population parameters between November 2009 and October 2010. During the survey we focused on the local Artemia populations to investigate population dynamics, reproduction, brood size, and cyst and naupliar biometrics. Generally, the Artemia habitats in Anatolia were relatively shallow, and thus they were subject to major seasonal fluctuations. Dramatic declines in population size in Tuz and Acıgöl Lakes were found during this study. All Artemia populations were …

Relationship Of Sociodemographic Factors With Serum Levels Of Vitamin D In A Healthy Population Of Pakistan, Khalida Iqbal, Najmul Islam, Naseema Mehboobali, Ali Asghar, Saleem Perwaiz Iqbal, Mohammad Perwaiz Iqbal

Department of Biological & Biomedical Sciences

High prevalence of vitamin D deficiency has been reported from Pakistan. Association of sociodemographic factors with vitamin D status has received little attention in this region. Therefore, we embarked on investigating the relationship of sociodemographic factors with vitamin D levels in a healthy Pakistani population. Venous blood from 226 healthy participants (age range 19-69 years) was collected and analyzed for serum concentrations of 25(OH) vitamin D [25(OH)D] and other related biomarkers. Demographic characteristics of the study participants were collected. Vitamin D deficiency (25(OH)D levels less than 20 ng/ml) was found to be 75% in this cohort. Gender, sunlight exposure and …

The Role Of Local Adaptation On Biting Performance In Trinidadian Guppies, Hannah E. Cohen

College of Graduate Studies: Theses & Dissertations

Divergent selection pressures in populations that occupy different environments can result in phenotypic differentiation in traits that provide a local fitness advantage. Trinidadian guppy (Poecilia reticulata) populations are separated by physical barriers such as waterfalls which result in repeated shifts in selective pressures from predator avoidance in high predation environments towards resource competition in low predation environments. Such shifts in selection pressures have previously shown that a range of locally adapted morphological and behavioral traits are changed. However, the role of local adaptation on biting behaviors remains unclear. I analyzed morphological differences such as body length, jaw position, …

Calculating Restaurant Failure Rates Using Longitudinal Census Data, J. J. Healy, Máirtín Mac Con Iomaire

Articles

Failure rates in the restaurant industry are popularly perceived to be far higher than they actually are. This paper calculates failure rates in the Irish Food and Drinks Sector (IFDS), for the first time, using longitudinal census data from the Central Statistics Office (CSO) in Ireland, which follows the European statistical classification of economic activity (NACE). The results are compared with previously published literature on restaurant failure rates in the United States of America. This study also compares IFDS failure rates with other industry sectors in Ireland (construction, manufacturing). Drawing on Stinchcombe’s ’liability of newness’ theory, the informal fallacies theory …

Environmental Predictors For The Distribution Of The Caspian Green Lizard, Lacerta Strigata Eichwald, 1831, Along Elevational Gradients Of The Elburz Mountains In Northern Iran, Anooshe Kafash, Sohrab Ashrafi, Annemarie Ohler, Benedikt Rudolf Schmidt

Turkish Journal of Zoology

Within its range, the Caspian green lizard, Lacerta strigata, occurs in the Elburz Mountains (northern Iran) at elevations from below sea level to approximately 2700 m a.s.l. To determine the environmental factors affecting the distribution of this lizard, we used an ensemble approach to model the distribution of the Caspian green lizard (Lacerta strigata) in Iran using four algorithms (generalized boosted model, maximum entropy, generalized linear model, random forest). Results revealed that low-elevation habitats between the Elburz Mountains and the Caspian Sea are the most suitable habitats for the species. The normalized difference vegetation index (NDVI), annual precipitation (both with …