Life Sciences Commons^™

Crop Tree Enhancement Of Green Ash (Fraxinus Pennsylvanica) In A West Tennessee Hardwood Bottom, John Luke Bowers

Masters Theses

Crop tree enhancement is a forest management technique undertaken to maintain, enhance, and improve the species composition, growth rate, and stem quality of stands so that management objectives may be better and more quickly accomplished. In 1996, a crop tree enhancement study involving green ash (Fraxinus pennsylvanica) in a 16-year-old, naturally regenerated, mixed-species, pole-sized, bottomland hardwood stand was initiated at Ames Plantation in West TN. Treatments included a crown-touching release, a crown-touching release plus one-time fertilizer application, and a control, applied in a randomized block design with five 25-crop tree repetitions of the three treatments. Initial crop tree …

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Beneficial Effects Of Naringenin And Indomethacin On White And Brown Adipocytes, Jamie Ann Kearns

Masters Theses

As obesity continues to grow and medical costs in the United States are estimated at $147 billion annually, novel ways to prevent and treat obesity are needed. One approach is to promote thermogenesis to improve energy balance by increasing the activities of thermogenic brown and beige adipocytes.

Naringenin, a citrus flavanone, has been shown to act as anti-inflammatory and lipid lowering agent as well as activate PPARgamma. However, it is unclear whether it can activate thermogenic activity in white adipocytes, i.e., promote formation of beige adipocytes. Indomethacin (INDO) is an FDA approved drug used to treat pain related to inflammation …

A Population Genetics Study Of Discula Destructiva, The Causal Agent Of Dogwood Anthracnose, Kristie Lynn Mantooth

Masters Theses

Flowering dogwood (Cornus florida L.) is prized as an ornamental and contributes millions of dollars to the economy through tourism and sales each year. Dogwood anthracnose, caused by Discula destructiva Redlin, was observed in the late 1970s on the east and west coasts of the United States and by 1991 had quickly spread throughout much of the native ranges of C. florida and C. nuttalli. The objectives of this study were to investigate the genetic diversity and population structure of D. destructiva using simple sequence repeats (SSRs), and to test the cross-transferability of these markers to other Discula …

Reasons Youth Choose Or Do Not Choose To Be Involved In 4-H Livestock Projects In Tennessee, Leigh Erin Fuson

Masters Theses

The purpose of this study was to find reasons youth choose or do not choose to be involved in 4-H livestock projects. Livestock projects are an important part of 4-H youth development because they teach life skills like responsibility and hard work. However, many youth are unable to participate or do not have the interest. This study sought to discover what motivates some youth to become involved in a livestock project and why others do not.

Focus groups were used as the data collection tool. Two groups of youth livestock participants and two groups of non-livestock participants were utilized. Themes …

Effect Of Varying Rumen Degradable And Undegradable Protein On Milk Production And Nitrogen Efficiency In Lactating Dairy Cows Under Summer Conditions, Jeffrey D. Kaufman

Masters Theses

The objective is to determine the effect of reducing nitrogen input through feeding low rumen degradable protein (RDP) and rumen undegradable protein (RUP) proportions on milk production, nitrogen efficiency and metabolism in heat-stressed cows. Forty-eight mid-lactating, Holstein cows were assigned to treatments using a randomized block design in a 2x2 factorial arrangement of treatments (n = 12/treatment). Treatments included two levels of RDP (10 and 8%) and two levels of RUP (8 and 6%). From d 1 to 21, a common diet (10% RDP-8% RUP) was fed to cows followed with their respective treatment diets fed from d 22 to …

Assessing Tennessee Livestock Producers' Awareness, Attitudes And Perceptions Of Right-Of-Way Hay Harvesting, Sarah Joy Maccaro

Masters Theses

In the state of Tennessee, statute 54-5-134, cutting hay along controlled access highway right-of-way, gives Tennessee agriculturalists the right to harvest hay along interstate medians and shoulders. Current maintenance is contracted out to private mowing companies and paid for by Tennessee taxpayers. Relatively few studies have been published on the topic of right-of-way hay harvesting, so this study was preliminary in nature. Through a questionnaire, this study sought to assess Hickman, Dickson, Williamson, Wilson and Rutherford county livestock producers’ current awareness, attitudes, and barriers concerning right-of-way hay harvesting as well as to conduct economic impact analyses to determine producers’ willingness …

Intercanine Distance Used As A Measure To Rule Out Biters In Bite Mark Forensics, Alana Joy Scudiere Ohana

Masters Theses

The science of identification by bite mark analysis has recently been called into serious question. (Reesu and Brown 2016) Human dentition is truly variable, but often not unique. When animal bites are considered, a proper ID of the perpetrator is nearly impossible. Primary distortion (when the bite is made) and secondary distortion (during decomposition or healing) both further disrupt landmarks that might be used for identification. (Sheasby and MacDonald 2001) Using only ink marks and intercanine distance on live subjects, this study attempts to determine maximum distortion possible for a variety of bite mark locations on skin. (Pretty and Sweet …

Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado

Masters Theses

Obesity and insulin resistance have been linked to prolonged interovulatory period, aberrations in the estrous cycle, and continuous reproductive activity during the non-breeding season. EMS has been determined to influence the intrafollicular environment of mare ovaries. In humans, insulin resistance has been linked to polycystic ovaries as part of Polycystic Ovarian Syndrome (PCOS). A study was conducted to determine 1) the impact of insulin resistance on follicle growth and size at ovulation, and 2) whether predicted ovulatory follicles respond to hCG administration in Insulin-resistant (IR) mares. Mares were selected for the study based on insulin sensitivity and separated into an …

Effects Of Synthetic Turf And Shockpads On Impact Attenuation Related Biomechanics During Drop Landing, Hang Qu

Masters Theses

Synthetic turf has been widely utilized in sports since 1964. Discrepancies, however, in injury incidence on synthetic turf and natural grass have been reported throughout studies. Adding a shock pad under synthetic turf carpet is claimed to aid in energy absorption and decrease impact loading. Although some studies have conducted materials tests and compared mechanical characteristics of synthetic turf with different shock pads, no studies have examined biomechanical characteristics of impact related human movements on an infilled synthetic turf system with different underlying shock pads. The purpose of this research was to investigate effects of an infilled synthetic turf with …

Effects Of Wider Step Width On Knee Biomechanics In Obese And Healthy-Weight Participants During Stair Ascent, Derek Scott Yocum

Masters Theses

An increased likelihood of developing obesity-related knee osteoarthritis may be associated with increased peak internal knee abduction moment. Increases in step width may act to reduce this moment. This study focused on how step width influenced the knee joint during stair ascent by healthy and obese participants. Participants ascended stairs while walking at their preferred speed and under one of two step width conditions – preferred and increased. Obese participants experienced greater mediolateral and vertical ground reaction forces (GRFs), as well as increased peak knee extensor moments and push-off peak internal knee adduction moments. The findings of this study indicate …

Effect Of Omega-3 Polyunsaturated Fatty Acid (N-3 Pufa) Supplementation To Lactating Sows On Growth And Indicators Of Stress In The Post-Weaned Pig, John M. Mcafee

Masters Theses

The first experiment was designed to determine the concentration of protected fish oil product (PFO), as Gromega^TM, to be added that would sufficiently decrease the polyunsaturated fatty acid (PUFA) ratio in the sows’ milk and colostrum. Of the 3 diets tested (0.25%, 0.5% and 1%) with a control (0% PFO), only the 1% PFO diet had an effect on the PUFA concentrations. The docosahexaenoic acid (DHA) concentration tended (P = 0.05) to be greater in the 1% PFO diet for both colostrum and milk samples. A second experiment was designed to …

Characterization Of Fusarium Species And Alternaria Alternata, And Their Effects On Switchgrass Health And Chemical Components, Sara Beth Collins

Masters Theses

Panicum virgatum L., readily referred to as Switchgrass, is a perennial warm-season bunch grass, used as an alternative energy source for biofuel production. There is insufficient research on switchgrass pathogens, and is expected that an increase in disease pressure will result as more land is reserved for this perennial crop. The purpose of this research was to identify and characterize pathogenic Alternaria alternata and Fusarium species on Switchgrass (Panicum virgatum L.), and to evaluate their impact on stand establishment and plant health. Molecular identifications of fungal isolates obtained from infected commercial switchgrass seed yielded eight species (A. alternata, …

Rapid Molecular Detection And Population Genetics Of Pityophthorus Juglandis, A Vector Of Thousand Cankers Disease In Juglans Spp., Emel Oren

Masters Theses

Thousand Cankers Disease (TCD) is a disease complex involving the fungal pathogen Geosmithia morbida, an insect vector Pityophthorus juglandis, and the hosts, Juglans spp. and Pterocarya spp. Signs and symptoms of TCD include crown thinning due to branch dieback, yellowing and wilting of the leaves, appearance of epicormic shoots, numerous entrance/exit holes, gallery formation by P. juglandis, and the development of small, dark brown cankers underneath the bark. TCD originally described from western U.S., has now expanded to eastern U.S. and northwestern Italy. The disease complex is often difficult to diagnose due to the absence of symptoms …

Understanding Stakeholder Attitudes And Involvement In Habitat Conservation Plans And The Endangered Species Act, Kyle Andrew Rodgers

Masters Theses

The Endangered Species Act (ESA), established in 1973, was a landmark piece of environmental legislation and remains the standard for endangered species conservation. Implementation of the ESA has often been framed as pitting economic development against species conservation, inciting passions for and against endangered species conservation. The strength of opposing public opinions is highlighted by high-profile controversies such as those around the snail darter, northern spotted owl and the greater sage grouse. In an attempt to reduce conflict, the US Fish and Wildlife Service (USFWS) increasingly seeks to utilize collaborative, stakeholder-based processes that address stakeholder interests, attitudes, and values.

In …

Lignin Maximization: Analyzing The Impact Of Different Feedstocks And Feedstock Ratios Using Organosolv Fractionation, Marc Banholzer

Masters Theses

Over-exploitation of fossil fuels coupled with increasing pressure to reduce carbon emissions are prompting a transition from conventional petrochemical feedstocks to sustainable and renewable sourced carbon. The use of lignocellulosic biomass as a feedstock for integrated biorefining is of current high interest, as separation into its component parts affords process streams of cellulose, hemicellulose and lignin, each of which can serve as a starting point for the production of biobased chemicals and fuels. Given the large number of potential sources of lignocellulosic feedstocks, the biorefinery will need to adapt to the supplies available over a normal growing season. Of particular …

Comparison Of Mesophyll Protoplast Isolation And Transformation Between Panicum Virgatum And Panicum Hallii, Andrea Grace Collins

Masters Theses

Protoplasts are appropriate targets for genome editing, DNA functional screens and transgenesis. This project focuses on the comparison of inexpensive mesophyll protoplast isolation via the use of food-grade enzymes and transformation between diploid Panicum hallii Vasey (PAH) and polyploid cellulosic feedstock Panicum virgatum L (switchgrass), a relative of PAH. PAH has great potential as a C4 model species for crop and bioenergy research. Here an inexpensive switchgrass and PAH mesophyll protoplast isolation and transformation system was developed; the first protoplast system for PAH. Using low-cost commercial food-grade enzymes, a cost reduction of ~1000-fold was achieved compared to traditional protoplast isolating …

An Online Study Of Undergraduates' Knowledge, Awareness, And Attitudes Of Preconception Care, Kelly Jean Crusenberry

Masters Theses

Background: The majority of pregnancies in the United States are unplanned. Health status and health-related behaviors such as poor nutrition, alcohol consumption, and/or tobacco use, occurring prior to conception, have been linked to poor obstetric outcomes for mothers and their offspring, many of which can result in lifelong challenges. Knowledge, awareness, and attitudes can be predictors of health-related behaviors, and preconception care and education may reduce risk of some of these poor obstetric outcomes. Undergraduate students are at an increased risk for many of these risky behaviors and for unplanned pregnancies, as compared to older individuals. However, little is known …

The Effect Of Heat Stress And Essential Amino Acids On Production And Metabolism Of Lactating Dairy Cattle, Kimberly Rose Kassube

Masters Theses

Heat stress (HS) causes decreases in production of lactating cattle that is only partially explained by decreases in intake. Evidence suggests that changes in energy and protein metabolism occur to cope with the impact of HS. The objective of this thesis was to determine if the effect of jugular infusion of essential amino acids (AA) ameliorated the negative effects of HS in milk production and metabolism. Twelve multiparous lactating Holstein cows were used in a crossover design to evaluate the effect of thermoneutral (THN) and HS environments along with the absence (CTL) …

Testing The Temporal Stability Of The Climate Response Of Tree Species At Norris Dam State Park, Tennessee, U.S.A., Allison Elizabeth Ingram

Masters Theses

Temporal stability of the climate-tree growth relationship means that over time, tree species were responding to a specific climate variable and continue to respond to that variable into the present. The stability of this response is important to test prior to attempting to reconstruct past climate. In this study, I sampled oaks (white oak = Quercus alba L. and chestnut oak = Quercus montana Willd.) and pines (Virginia pine = Pinus virginiana Mill. and shortleaf pine = Pinus echinata Mill.) growing in Norris Dam State Park in eastern Tennessee and tested the temporal stability of these species and their potential …

Improving Aedes Mosquito Surveillance And La Crosse Virus Screening In Eastern Tennessee, Cassandra Urquhart

Masters Theses

La Crosse virus (LACV), transmitted by infected Aedes triseriatus, Ae. albopictus, and Ae. japonicus mosquitoes is the leading cause of pediatric arboviral encephalitis. Severe cases of LAC encephalitis occur in individuals 16-years-old or younger and may cause permanent neurological damage or fatality. No vaccines exist making mosquito control and disease prevention crucial to public health. Effective screening and surveillance practices are key components to these goals. While a number of standard mosquito surveillance methods exist, continuous testing and improved understanding of vector biology to determine the best ways to implement these methods is important. Additionally, the current standard …

An Ecological Study Of The Kudzu Bug In East Tennessee: Life History, Seasonality, And Phenology, Kadie Elizabeth Britt

Masters Theses

The kudzu bug, Megacopta cribraria (Hemiptera: Plataspidae), an invasive species from Asia, was first discovered in the United States in 2009 in Georgia. It has since spread to other states, including Tennessee, where it has spread rapidly to numerous counties in four years. Its common name, kudzu bug, implies a potential benefit to management of the invasive species kudzu; unfortunately, the kudzu bug has shown little impact on reducing growth of kudzu. The kudzu bug causes agricultural, urban, and health-related concerns in the United States. Soybean losses by kudzu bug have exceeded 20% in some areas of the southeastern United …

Association Of Genotype At Drd2 With Growth And Reproductive Performance Traits In Bulls Grazing Toxic Endophyte-Infected Tall Fescue, Kaysie Jennings

Masters Theses

Fescue toxicosis can negatively impact growth and fertility of beef cattle grazing tall fescue infected with an endophytic fungus. The fungus produces ergot alkaloids that contribute to the hardiness of the plant, but can be detrimental to the animal if consumed. A single nucleotide polymorphism (SNP) in the dopamine receptor D2 gene (DRD2) has been associated with serum prolactin concentrations and hair coat scores in cattle grazing toxic endophyte-infected (TE) tall fescue; cattle with the GG genotype had decreased serum prolactin concentrations and increased hair coat scores. Separately, heifers with the AA genotype calved sooner than AG or GG heifers. …

Regional Dynamic Price Relationships Of Distillers Dried Grains In U.S. Feed Markets, Matthew Fulton Johnson

Masters Theses

Distillers dried grains with solubles (DDGS) is now a mainstream substitute in U.S. animal feed rations. DDGS is rich in fat and protein content and serves as a competitive feed source in livestock markets. The objective of this study is to identify dynamic price relationships among DDGS, corn, soybean meal, and livestock outputs in context of specific livestock sectors and their geographic location. Four locations associated with a predominant livestock sector are selected for analysis by measuring density and relative proportion of a livestock sector’s grain consumption at the county level. A vector error correction model is applied to post-mandate …

The Effects Of Actigraph Bandpass Filtering On Activity Counts During Continuous And Intermittent Lifestyle Activity, Samuel Robert Lamunion

Masters Theses

PURPOSE: The purpose of this study was to explore how increasing the upper limit of the bandpass filter frequency range affected accelerometer counts collected during treadmill walking and running, car driving and intermittent lifestyle activities METHODS: Part A included treadmill walking, running, and car driving (N=20) (mean ± [plus or minus] SD; age, 24.4±3.4 years; body mass index (BMI, 26.4±3.3 kg/m² [kilograms per meter squared]). Part B included ten lifestyle activities ranging from sedentary behaviors to vigorous intensities (N=30) (mean±SD; age, 23.0±2.3 years; BMI, 25.1±3.8 kg/m²). Participants wore an ActiGraph accelerometer (GT3X+ in Part A and GT9X …

Forage Availability And Nutritional Carrying Capacity For Cervids Following Prescribed Fire And Herbicide Applications In Young Mixed-Hardwood Forest Stands In The Cumberland Mountains, Tennessee, Jordan Scott Nanney

Masters Theses

I evaluated the influence of timber harvest combined with prescribed fire and/or herbicide in young mixed-hardwood forest on forage availability and nutritional carrying capacity (NCC) for elk (Cervus elaphus) and white-tailed deer (Odocoileus virginianus) at the North Cumberland Wildlife Management Area (WMA), July-August, 2013-15. I combined land cover data, forest management data, field management data, and forage availability data to model summer elk forage availability across the WMA.

I compared forage availability, NCC (animal days/ha) using 12 and 14% crude protein (CP) nutritional constraints, and vegetation composition among 6 young forest treatments, reclaimed surface mines (MINE), and closed-canopy mature forest …

Microbial Extracellular Enzymes In Marine Sediments: Methods Development And Potential Activities In The Baltic Sea Deep Biosphere, Jenna Marie Schmidt

Masters Theses

The deep biosphere is defined as the subsurface ecosystem in which little energy is available to microorganisms and microorganisms can live for thousands of years. Heterotrophic microbes survive in the deep biosphere even though organic matter is limited and highly recalcitrant in nature. Measuring microbial extracellular enzyme activity provides a potential means to evaluate the rate at which microorganisms are performing carbon remineralization in the energy limited sediment beneath the seafloor. Extracellular enzymes breakdown organic compounds so that the nutrients can move inside the cell and be used for energy. This study explored the role extracellular enzymes play in the …

Identification Of Potential Bacterial Surrogates For Validation Of Thermal Inactivation Processes Of Hepatitis A Virus, Marcel Schmidt

Masters Theses

Thermal treatment is a method for inactivating pathogens in a wide range of food products. Recent studies have shown that hepatitis A virus (HAV) has a D_72°C [D72 degree celcius] of 0.9 min in buffer which is greater than vegetative bacterial pathogens. Common surrogates, such as Listeria innocua, are not resistant enough to be used as surrogates for HAV, thus, new surrogates need to be identified. The purpose of this study was to compare the thermal inactivation kinetics (D- and z-values) of Staphylococcus carnosus in different foods and different incubation temperatures to identify a potential surrogate for HAV. …

Evaluation Of Total Mercury And Methylmercury Concentrations Of Terrestrial Invertebrates Along Lower East Fork Poplar Creek In Oak Ridge, Tennessee, Chelsea Lynden Standish

Masters Theses

Mercury (Hg) and methylmercury (MeHg) are environmental concerns due to their abilities to cause neurological, reproductive, and other physical damage to wildlife. Lower East Fork Poplar Creek (LEFPC), stemming from the Y-12 National Security Complex, located in Oak Ridge, TN, has elevated concentrations of inorganic mercury, a majority of which was released between 1950 and 1963. This inorganic mercury has been, and is currently, converted to methylmercury. An ecological assessment in 2011 revealed high concentrations of methylmercury in riparian spiders along LEFPC. These results suggested the transfer of mercury from aquatic to terrestrial systems may be higher than previously expected …

Retained Ownership Profitability Of Beef Cattle Originating In Tennessee, Minfeng Tang

Masters Theses

Retained ownership is a marketing strategy that can be used by cow-calf operators to benefit from the potential increase in fed cattle prices. We analyze the profitability of retained cattle ownership from 2005 to 2015 for cow-calf producers in Tennessee. We also determine the impact of steer/heifer characteristics (e.g., average daily gain, feed conversion) and producer choice decisions (e.g., placement weight, placement season, days on feed) on retained ownership profitability. Data on 2,953 head of cattle originating in Tennessee and finished in Iowa using a retained ownership strategy were collected. A mixed regression model explaining profitability was estimated with fixed …