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Assessing The Ecological Implications Of The Altered Flow And Sediment Regimes Of The Rio Grande Along The West Texas-Mexico Border, Demitra E. Blythe 2018 Utah State University

Assessing The Ecological Implications Of The Altered Flow And Sediment Regimes Of The Rio Grande Along The West Texas-Mexico Border, Demitra E. Blythe

All Graduate Theses and Dissertations

Large, exotic (those whose headwaters are in distant places) rivers are some of the most unique and diverse ecosystems on earth. Because they often flow through a multitude of biomes and climates, their waters are a vital resource not only for the organisms that inhabit these rivers, but for human societies as well. Thus, large rivers, like the Rio Grande, that flow through arid and agricultural regions are highly regulated and diverted. Regulation and dewatering upset a river’s natural flow regime (e.g., magnitude, duration, timing of large flood events), subsequently impacting the river’s ability to transport its ...


Identification Of Sperm Chromatin Proteins As Candidate Markers Of Stallion Fertility, Chelsea C. Ketchum 2018 Utah State University

Identification Of Sperm Chromatin Proteins As Candidate Markers Of Stallion Fertility, Chelsea C. Ketchum

All Graduate Theses and Dissertations

During spermatogenesis, histones are largely replaced by transition proteins and protamines in normal stallions. Incomplete nucleoprotein exchange results in the abnormal retention of histones and transition proteins, which is an indicator of poor sperm quality. Equine nucleoprotein exchange has not previously been investigated in detail, so that equine sperm chromatin quality problems, which are often responsible for poor breeding performance of stallions, are not well understood. In order to characterize chromatin remodeling events in stallion spermatogenesis and to identify proteins indicative of sperm chromatin defects, such as excessive amounts of histones, we identified antibodies that recognize equine testis-specific proteins of ...


Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller 2018 Utah State University

Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller

All Graduate Theses and Dissertations

Organic wheat grown under dryland conditions encounters challenges such as limited nutrients and water. Maintaining organic wheat production requires solutions to these problems in order to retain economic sustainability for the farmers.

Research on biochar and compost have been conducted globally. Despite well known benefits of compost on soil and crop production, few organic farmers apply compost to their fields. Research on biochar is still new. Biochar is charcoal created from pyrolyzing agricultural material under conditions of low oxygen and high heat. Many studies claim that biochar is a valuable soil amendment for improving organic production and reducing environmental pollution ...


An Evaluation Of Bull Trout Movement Dynamics In The Walla Walla River, Courtney Newlon 2018 Utah State University

An Evaluation Of Bull Trout Movement Dynamics In The Walla Walla River, Courtney Newlon

All Graduate Theses and Dissertations

Bull trout are a fish species listed as threatened under the Endangered Species Act.Historically, they ranged from Northern California at the southernmost extent, into Canada at the northern most extent, and east into Nevada and Montana. Bull trout are highly migratory and require large, unfragmented habitats to persist and are thus highly susceptible to human induced land-use practices. The goal of my thesis was to obtain a better understanding of bull trout movement patterns in the Walla Walla River, Washington using complimentary techniques; Passive Integrated Transponder (PIT)technology and otolith microchemistry. PIT tags can be injected into a fish ...


The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni 2018 East Tennessee State University

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not ...


Prioritizing Chemical Constituents In Tobacco Products And Smoke To Predict Developmental Osteotoxicity In Human Embryonic Stem Cells, Joseph Madrid 2018 California State University, San Bernardino

Prioritizing Chemical Constituents In Tobacco Products And Smoke To Predict Developmental Osteotoxicity In Human Embryonic Stem Cells, Joseph Madrid

Electronic Theses, Projects, and Dissertations

Though it is well known that tobacco related products can cause prenatal maldevelopment, very little is known on how tobacco products affect bone tissue as it develops in the embryo. Identifying which chemicals can induce the greatest harm to the prenatal skeletal system is an improbable task as there are over 7,000 chemicals in tobacco smoke alone. We hypothesized that the Toxicological Priority Index (ToxPI) program can be used to rank osteogenic cytotoxicity potential to aid in the assessment of what chemicals out of the thousands can cause osteogenic differentiation inhibition. ToxPI aggregates information from various assays and incorporates ...


Geospatial Modeling Of Land Cover Change In The Chocó-Darien Global Ecoregion Of South America: Assessing Proximate Causes And Underlying Drivers Of Deforestation And Reforestation, José Camilo Fagua 2018 Utah State University

Geospatial Modeling Of Land Cover Change In The Chocó-Darien Global Ecoregion Of South America: Assessing Proximate Causes And Underlying Drivers Of Deforestation And Reforestation, José Camilo Fagua

All Graduate Theses and Dissertations

The Chocó-Darien Global Ecoregion (CGE) in South America is one of 25 global biodiversity hotspots prioritized for conservation. I performed the first land-use and land-cover (LULC) change analysis for the entire CGE in this dissertation. There were three main objectives: 1) Select the best available imagery to build annual land-use and land-cover maps from 2001 to 2015 across the CGE. 2) Model LULC across the CGE to assess forest change trends from 2002 to 2015 and identify the effect of proximate causes of deforestation and reforestation. 3) Estimate the effects of underlying drivers on deforestation and reforestation across the CGE ...


Evaluation Of Motor Cortex Neuronal Morphology In Developmental Hyperserotonemia Rat Model, Colten Z. Dillinger 2018 Missouri State University

Evaluation Of Motor Cortex Neuronal Morphology In Developmental Hyperserotonemia Rat Model, Colten Z. Dillinger

MSU Graduate Theses

Fetal serotonin levels are involved in the development of the serotonergic system in an autoregulatory manner as well as the organization and connectivity of non-serotonergic neurons. Insufficient serotonin levels during development result in improper neuronal maturation and decreased synaptogenesis. Conversely, excess developmental serotonin levels can alter the progression of serotonergic neurons, ultimately resulting in a chronic decrease of serotonin in the developed brain via a negative feedback mechanism. There is a known correlation between autistic patients and chronically decreased brain serotonin concentrations; this is potentially implicated in the impaired development of the autistic brain. Incomplete or delayed development of motor ...


Timber Talk, Vol. 56, No. 4, December 2018, Nebraska Forest Service, University of Nebraska - Lincoln 2018 University of Nebraska - Lincoln

Timber Talk, Vol. 56, No. 4, December 2018, Nebraska Forest Service, University Of Nebraska - Lincoln

Timber Talk: Nebraska Forest Industry Newsletter

In This Issue:

Lumber Market Reports

Hardwood Lumber Prices

NOTE FROM EDITOR: Transitioning to Electronic Delivery Only

NDA Expands EAB Quarantine

Forest Products Grants Available

Wildfires and Communities in Nebraska

Forest Industry Spotlight: “Good Neighbor Authority” in Nebraska

Trading Post

Timber Sales


Forage News [2018-12], University of Kentucky Department of Plant and Soil Sciences 2018 University of Kentucky

Development And Application Of A Reverse Genetics System For Zika Virus, Jordan C. Frank 2018 Utah State University

Development And Application Of A Reverse Genetics System For Zika Virus, Jordan C. Frank

All Graduate Theses and Dissertations

Zika virus (ZIKV) has emerged in many regions of the world, with infection outcomes spanning from no apparent illness to crippling nervous system disease. ZIKV and its close relatives, West Nile virus, Japanese encephalitis virus, dengue virus, and yellow fever virus are primarily transmitted by mosquitoes. Three ZIKVs were selected: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015), whose place of origin and time of isolation differ substantially. Stable, complementary DNA (cDNA) copies of the three ZIKV RNA genomes were cloned to examine the significance of viral and host genetic variations in directing ZIKV infection outcomes. Using ...


The Nesting Ecology Of Woodpeckers In The Eastern Cascades And Their Interactions With Nest Competitors And Predators, Samuel D. Cowell 2018 Utah State University

The Nesting Ecology Of Woodpeckers In The Eastern Cascades And Their Interactions With Nest Competitors And Predators, Samuel D. Cowell

All Graduate Theses and Dissertations

Woodpeckers create nesting cavities for other birds and animals in forests. This creates dynamic interactions between both woodpeckers and these other animals. Using video cameras, we documented direct behavioral interactions between nesting woodpeckers and other animals in the Eastern Washington Cascades during the 2015 and 2016 breeding seasons. Additionally, we offered 937 students in a General Biology laboratory course to participate in this original research opportunity and described and the impact the experience had on the participants as well as the researchers.

In 2015, Western Blubebirds took over two active Black-backed Woodpecker nests by physically attacking the woodpeckers. In 2016 ...


Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza 2018 Iowa State University

Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza

Agronomy Publications

The anticipated world population growth emphasizes a need to produce more food on less land. Cutting-edge technologies, including genetic engineering, can help to develop improved crop varieties and protect natural resources. In spite of the potential for genetically-modified (GM) crops to make crop production more efficient, they remain a polarizing issue due to safety concerns. This paper provides an overview of the risk assessment process. The safety of Bacillus thuringiensis (Bt) proteins is used as an example for how risk assessment is applied to GM crops. Risks associated with GM crops have proven to be low to non-existent. Developing countries ...


Role Of P300 Zz Domain In Chromatin Association And Histone Acetylation, Yongming Xue 2018 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Role Of P300 Zz Domain In Chromatin Association And Histone Acetylation, Yongming Xue

UT GSBS Dissertations and Theses (Open Access)

Transcription is strictly regulated by numerous factors including transcription coactivators. The p300 protein and its close paralogue CREB-binding protein (CREBBP, aka CBP) are well-known transcriptional coactivators that have intrinsic lysine acetyltransferase activity. The functions of p300/CBP largely rely on their capabilities to bind to chromatin and to acetylate the histone substrates. However, the molecular mechanisms underlying the regulation of these processes are not fully understood.

Through combination of various biochemical, biophysical and molecular approaches, we show that the ZZ-type zinc finger (ZZ) domain of p300 functions as a histone reader that specifically binds the N-terminal tail of histone H3 ...


Diversification Across A Dynamic Landscape: Phylogeography And Riverscape Genetics Of Speckled Dace (Rhinichthys Osculus) In Western North America, Steven Michael Mussmann 2018 University of Arkansas, Fayetteville

Diversification Across A Dynamic Landscape: Phylogeography And Riverscape Genetics Of Speckled Dace (Rhinichthys Osculus) In Western North America, Steven Michael Mussmann

Theses and Dissertations

Evolution occurs at various spatial and temporal scales. For example, speciation may occur in historic time, whereas localized adaptation is more contemporary. Each is required to identify and manage biodiversity. However, the relative abundance of Speckled Dace (Rhinichthys osculus), a small cyprinid fish in western North America (WNA) and the study species for this dissertation, establishes it an atypical conservation target, particularly when contrasted with the profusion of narrowly endemic forms it displays. Yet, the juxtaposition of ubiquity versus endemism provides an ideal model against which to test hypotheses regarding the geomorphic evolution of WNA. More specifically, it also allows ...


Genetic And Epigenetic Investigations On Pulmonary Hypertension Syndrome In Meat Type- Chickens, Khaloud Alzahrani 2018 University of Arkansas, Fayetteville

Genetic And Epigenetic Investigations On Pulmonary Hypertension Syndrome In Meat Type- Chickens, Khaloud Alzahrani

Theses and Dissertations

This dissertation presents a collection of studies that investigate the genetic and epigenetic associations to ascites phenotype in broiler chickens. Ascites is a significant metabolic disease associated with fast-growing meat-type chickens (broilers) and is a terminal result of pulmonary hypertension syndrome PHS. It is a multi-factorial syndrome caused by interactions between genetic, physiological, environmental, and managemental factors. It was estimated that ascites accounts for losses of about US$1 billion annually worldwide and for over 25% of broilers mortality. Although traditional and molecular genetic methods in the selection and in performance improvements, has greatly reduced ascites frequency, yet it has ...


Spotted Wing Drosophila (Drosophila Suzukii) In Arkansas: Winter Morphs, Wild Hosts, And Fungal Control, Rosalee Knipp 2018 University of Arkansas, Fayetteville

Spotted Wing Drosophila (Drosophila Suzukii) In Arkansas: Winter Morphs, Wild Hosts, And Fungal Control, Rosalee Knipp

Theses and Dissertations

Drosophila suzukii (Matsumura), or spotted wing drosophila (SWD), is an invasive fruit fly pest that was first found in the United States in 2008. Unlike native Drosophila, SWD females have a serrated ovipositor that allows them to attack ripening fruit. Since its introduction, it is unclear how and where they overwinter in Arkansas, what local hosts they utilize and what potential alternative tactics can be used to combat this pest. In states north of Arkansas, winter morphs (WM) of SWD are larger, darker pigmented, and can survive colder temperatures than SWD flies found in the summer. These WM were found ...


Identifying And Assessing Conflicts Between Future Development And Current Migratory Bird Habitat Around Farmington Bay, Utah, Aubin A. Douglas 2018 Utah State University

Identifying And Assessing Conflicts Between Future Development And Current Migratory Bird Habitat Around Farmington Bay, Utah, Aubin A. Douglas

All Graduate Plan B and other Reports

Every year, the Great Salt Lake (GSL) and its associated wetlands provide critical habitat for over 250 migratory bird species from both the Pacific and Central Flyways. The GSL borders the Wasatch Front, which is the fastest growing and most populous region in Utah. To support the ever-increasing working population, the government of Utah aspires to increase the robust economic growth of the region through economic incentives and development of infrastructure. As this area continues to develop, greater pressure will be placed on the surrounding natural resources, including the GSL, its wetlands, and the open space and agricultural land that ...


Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie 2018 University of Arkansas, Fayetteville

Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie

Theses and Dissertations

Temperature conditions during the transportation to the processing facility of commercial broilers have a direct impact on the meat texture, specifically maximum shear force and shear variation of cooked breast meat. Analysis of a calendar year of flock data (N=346), reveals that the largest impact of transport conditions, specifically temperature, is on the standard deviation of the flocks range of cooked shear values. The optimal transport temperature that yields broiler breast meat with average flock minimum shear and standard deviation values is approximately 60°F. The shear values for flocks at or near 60°F are on average 1 ...


Evolutionary Dynamics Of Brown Treesnake (Boiga Irregularis) Reproductive Ecology, With Implications For Invasive Species Control, Brenna Aaren Levine 2018 University of Arkansas, Fayetteville

Evolutionary Dynamics Of Brown Treesnake (Boiga Irregularis) Reproductive Ecology, With Implications For Invasive Species Control, Brenna Aaren Levine

Theses and Dissertations

Invasive species represent major threats to biodiversity, global economies, and human health. Consequently, extensive research has been directed towards improving methods that restrict and contain them. Yet, control measures can also act as agents of selection by significantly impacting the reproductive capacity of invasives (in the context of “eco-evo” dynamics). The end result is that control measures subsequently alter the fitness landscape of an invasive over ecologically-relevant time, and lose their efficacy by so doing. However, adaptive management can be promoted by investigating the relationships between reproductive ecology, strength of selection, and (additive) genetic variation. In short, effective control can ...


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