Life Sciences Commons^™

Rice Value Chain Development And Policy Sequencing In Southern Africa, Sandratra M. Razafinjoelina

Graduate Theses and Dissertations

In the wake of the 2008 food crisis, net food importing countries questioned the reliance on the volatile world market to meet their food demand. Consequently, the necessity to be selfsufficient returned to the forefront of national priorities. In Africa, the Coalition for African Rice Development (CARD) initiative was initiated and aimed to double rice production in the continent by 2018, with the eventual goal of achieving self-sufficiency in rice production. To attain this goal, each of the 23 CARD member countries drafted a comprehensive value chain upgrading strategy called the National Rice Development Strategy (NRDS). This study intends to …

Environmental And Climatic Constraints On Large-Scale Camelina Production In Eastern Arkansas, Benjamin Robert Tracy

Graduate Theses and Dissertations

Camelina sativa is a cold weather crop that is typically grown in semi-arid environments in the Western United States, usually as a spring crop, but sometimes during the winter. Research analyzing climate data and soil hydrology is important to better understand the environmental and terrain conditions necessary for Camelina farming wherever it is proposed for large-scale production. This study focused on various conditions and constraints pertaining to the potential for Camelina as a crop biofuel in Eastern Arkansas. Due to interest in the economic potential of crop biofuels in this area, and in particular the low input costs for Camelina, …

Quantifying Terrestrial Ecosystem Carbon Dynamics With Mechanistically-Based Biogeochemistry Models And In Situ And Remotely Sensed Data, Shaoqing Liu

Open Access Dissertations

Terrestrial ecosystem plays a critical role in the global carbon cycle and climate system. Therefore, it is important to accurately quantify the carbon dynamics of terrestrial ecosystem under future climatic change condition. This dissertation evaluates the regional carbon dynamics by using upscaling approach, mechanistically-based biogeochemistry models and in situ and remotely sensed data.

The upscaling studies based on FLUXNET network has provided us the spatial and temporal pattern of the carbon fluxes but it fails to consider the atmospheric CO2 effect given its important physiological role in carbon assimilation. In the second chapter, we consider the effect of atmospheric CO2 …

Dopamine D1 Receptor Activity In The Basolateral Amygdala Is Important For Mediating Fear, Reward And Safety Discrimination Learning, Ka Ho Ng

Open Access Theses

Post traumatic stress disorder (PTSD) patients frequently show impairment in safety learning (Jovanovic, Kazama, Bachevalier, & Davis, 2012). Since the amygdala is known to be critical for emotional processing(Wassum & Izquierdo, 2015) and dopamine signaling in the amygdala is important for mediating both fear and reward learning, current experiments examined the role of dopamine signaling in the BLA in mediating both safety learning and reward seeking. We manipulated dopamine D1 receptor activity with a D1 receptor agonist (SKF 38393) or D1 receptor antagonist (SCH23390) either systemically or infused directly into the BLA 20 minutes prior to training rats in a …

Relationship Among Genetic And Physiological Biomarkers, And Horse Characteristics, Casey Orr

Graduate Theses and Dissertations

The objective of this study was to evaluate relationships among genetic and physiological biomarkers and phenotypic characteristics in horses. Three breeds (Quarter Horse, Thoroughbreds, Miniatures), and five genes of interest (leptin, ghrelin, cytochrome P450, glucocorticoid receptor, and lactate dehydrogenase) were the basis of the investigation. Genomic DNA was extracted from buffy coat samples of Quarter Horses (n = 21), Thoroughbreds (n = 26), and Miniatures (n = 34). Data were analyzed using MIXED MODEL procedures of SAS, with the main effects of breed and SNP genotype. Horse was the experimental unit, and dependent variables were classified as physical, cell differentials, …

Effect Of Light Intensity On Production Parameters And Feeding Behavior Of Broilers, Maurice Raccoursier Frost

Graduate Theses and Dissertations

This project was performed in two parts. The first was focused on light intensity as it affects performance. A randomized complete block design (RCBD) was performed. Broilers, Cobb 500 (n = 1584) were housed in 3 commercial houses (121.9 x 12.2 m). In each house birds were randomized and placed in 72 pens of 121.9 x 121.9 cm (22 bird/pen, males and females). All the treatment groups were provided with 24h light (L) during the first week and then 18L:6Dark (D) and 20 lux from day 7 to 14. The 3 intensity treatments of 5 lux (lx), 10 lx and …

Reflexivity: A First Demonstration, Melissa Jane Swisher

Open Access Dissertations

Currently, the emergent relation of reflexivity after training a set of baseline relations has not been demonstrated with any animal—human or nonhuman. True reflexivity can only be demonstrated if no identity (i.e., physically matching stimulus) relations are trained. In six experiments, the emergence of reflexivity and its opposite, anti-reflexivity, were explored. Pigeons received concurrent successive matching training on two or three arbitrary tasks: AB hue-form and BC form-hue (and AC hue-hue) matching. Once they had acquired these tasks, they were tested for BB (form-form) reflexivity or BB’ (form-form) anti-reflexivity matching. Most (10 of 13) pigeons that received three arbitrary tasks …

Evaluation Of Long-Acting Eprinomectin Compared To Conventional Anthelmintics In Cow/Calf Production, Elizabeth Ann Backes

Graduate Theses and Dissertations

Experiment 1, 83, newly weaned, fall-born crossbred heifer calves were allocated randomly to 1 of 3 anthelmintic treatments: 1) control (CON); 2) combination pour-on moxidectin and oxfendazole (MO); and 3) long-acting eprinomectin (LAE). Two preplanned orthogonal contrast statements were used: 1) to compare CON to treated cattle; and 2) to compare OXF to LAE. Heifer BW and BCS were greater (P≤0.02) from MO and LAE on d 112, 140, 154, 168, 182 compared to CON. Heifer cyclicity, estrous detection, natural service and overall pregnancy rates were greater (P≤0.02) for MO and LAE compared to CON. Cattle fecal egg counts (FEC) …

Recognition Training For Faces Across Age Gaps, William Blake Erickson

Graduate Theses and Dissertations

Face recognition is a problem that has theoretical and applied value. However, the fact of facial aging is rarely addressed in research and unmentioned in the major theories of face recognition. Facial aging also has ramifications for missing persons and fugitive cases, confounding attempts by law enforcement to recover these people whose last known images are years or decades out of date. This dissertation reports three studies aimed at measuring baseline age-gap recognition ability and testing various training regimens designed to increase accuracy rates for this unique kind of recognition task.

An Investigation Of Short-Term Plasticity In Human Motor Cortex, Matthew Alan Gannon

Graduate Theses and Dissertations

Transcranial magnetic stimulation (TMS) produces a transient magnetic field that activates underlying cortical tissue by eliciting an electrical discharge of the neurons in the targeted area. Repetitive TMS (rTMS) uses patterns of repetitive TMS pulses and has been reliably shown to produce changes in the state of cortical excitability outlasting the time of stimulation. One such protocol that has demonstrated states of increased excitability is intermittent theta burst stimulation (iTBS). This method applies high-frequency bursts (50Hz) of pulses every 200 ms in trains of ten bursts. The effects of and differences between rTMS protocols have been investigated since gaining popularity …

Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar

Graduate Theses and Dissertations

The use of antibiotics in poultry growth and disease control has led to antibiotics resistant problem in human beings, which is a big concern among consumers. With the necessity for judicious use of antibiotics in poultry production, alternative strategies to improve disease resistance in poultry production are necessary. The research is more inclined towards using the natural products available to grow healthier and antibiotic free meat animals. In the context of exploring natural and sustainable resource of alternative to antibiotics, the biochemical milieu of eggshell membranes (ESM) were analyzed by using mass spectrometry techniques including matrix assisted laser desorption ionization …

Geospatial Analysis Of Droughts, Rice And Wheat Production, And Agrarian Vulnerability: A District-Level Study Of The Self-Calibrated Palmer Drought Severity Index In India, Aaron Michael Shew

Graduate Theses and Dissertations

Droughts have affected more people than any other natural disaster in the last century, causing billions in economic damages and millions of deaths. As the Sea Surface Temperatures (SST) have heated in the Indian Ocean, drought patterns across South Asia have changed; the Indian monsoon has become more volatile and less predictable. In this study, monthly self-calibrated Palmer Drought Severity Index (sc-PDSI) data for the time period between 1950 and 2009 were interpolated to India’s districts; then the data were analyzed for changes in frequency and severity. The data were further evaluated using Anselin’s Local Moran’s I Statistic to elicit …

Evaluation And Selection Of A Bacillus Based Direct-Fed Microbial Candidate For In Situ Enzyme Production To Improve Gut Health Integrity, Bone Quality And Growth Performance In Poultry, Juan David Latorre Cardenas

Graduate Theses and Dissertations

During the last decade, the increasing interest in renewable energy sources has been changing the distribution of corn utilization from human and animal consumption to biofuel production, leading to a continuous rise in feed costs of livestock diets. Therefore, alternative feed ingredients such as distillers dried grains with solubles (DDGS), as well as cereals like wheat, barley, and sorghum have become part of the feed matrix to maintain or reduce production costs. However, these raw materials often contain a higher concentration of antinutritional factors in comparison to corn, including non-starch polysaccharides (NSP) which increase digesta viscosity and reduce nutrient absorption …

The Effect Of Voluntary Binge Caffeine And Ethanol Coexposure On Neurobehavioral Sensitivity To Cocaine In Male C57bl/6j Mice, Brandon M. Fritz

Open Access Dissertations

Recently, the co-consumption of highly caffeinated energy drinks and alcohol has become a public health concern. Consumption of these beverages has been linked to a wide variety negative consequences including alcohol poisoning, driving under the influence, physical harm, and sexual violence. The more protracted consequences of caffeinated alcohol consumption have received very little attention, however. Some evidence suggests that individuals that frequently consume energy drinks mixed with alcohol are more likely to develop an alcohol use disorder. Interestingly, both caffeine and alcohol use alone have been linked to polydrug abuse. It is therefore of interest whether combined caffeine and alcohol …

Efficacy Of A Novel Intranasal Zinc Solution On The Microbiome, Health, And Growth Performance Of High-Risk, Newly Received Stocker Cattle, Makenzie Foster

Graduate Theses and Dissertations

The objective of this study was to determine if using an intranasal zinc (Zn) solution would impact health and growth performance of high-risk stocker cattle. Male beef calves (n = 239; 3 arrival dates [block]; initial BW = 276 ± 2.4 kg) were stratified by arrival gender and BW and assigned to 1 of 2 treatments: 1) treated with 3 ml of a Zn solution containing 36.24 mg of Zn administered intranasally, or 2) control, in which calves were not treated. Calves were observed daily and if exhibiting signs of morbidity and a rectal temperature ≥ 40° C they were …

Economic Feasibility Of Aquaponics In Arkansas, Leah Ashley English

Graduate Theses and Dissertations

Concerns regarding population growth and resource scarcity have led to a recent renaissance of food production research. Over the past few decades, scientists have discovered new and innovative methods for growing food that, cumulatively, may hold the key to efficiently and sustainably feeding an ever-increasing world population. One method, known as aquaponics, has shown promise as being a sustainable solution for producing food locally in all parts of the world. Although many studies have shown aquaponic food production to be technically feasible, there are relatively few studies concerning the economic feasibility of aquaponics in various regions. To determine whether aquaponics …

A Regional Approach To Analysis Of Food Security Framework And Policies Of The Economic Community Of West African States (Ecowas), Hannah Elizabeth Shear

Graduate Theses and Dissertations

Food security is always a concern for consumers, but especially for those in West Africa, where the population of food insecure people has continued to grow over the past decade despite attempts by initiatives such as the World Food Program and the establishment of Millennium Development Goals. The people of West Africa are subject to repetitive natural disasters and are often in political upheaval. Many economic policies have been established to mitigate the impact that production disasters have on the consumers; one of these policies is the utilization of regional food reserves.

In 2010, the Economic Community of West African …

Evaluating The Impacts Of Respondent Errors In Arms: A Case Of Farm Service Agency Loans, Louise Nicole Mcminn

Graduate Theses and Dissertations

Many studies have used the U.S. Department of Agriculture’s (USDA) Agricultural Resource Management Survey (ARMS) to research various aspects involving the agricultural sector in the United States. Since nonresponse and inaccurate reporting may cause significant bias in statistical analysis, research was conducted to determine the magnitude of response error on the farm debt section of the ARMS Phase III. A multinomial logit model identified demographic, structural, and financial characteristics of FSA Farm Loan Program (FLP) borrowers who refused to indicate if they had end of year farm debt, or who accurately or inaccurately classified their farm operations as having end …

The Abundance And Distribution Of Mallards In The Lower Mississippi Alluvial Valley Of Arkansas, John Andrew Herbert

Graduate Theses and Dissertations

The management of wintering waterfowl in North America requires flexibility because of constantly changing landscapes and conditions. Many mallards use the lower Mississippi Alluvial Valley (MAV) for wintering habitat, making this an area of emphasis for improving management strategies. In this study, I used mallard observation data from 2009-2014 aerial surveys collected in the Arkansas portion of the lower MAV to explain the abundance and distribution and of mallards. Using spatial hierarchical models and breaking covariate data to 2x2 km grid cells, I analyzed how covariates relate to the changes of abundance and distributions within and among surveys. Mallard abundance …

Responses Of Two Strains Of Broilers To Diets Varying In Essential Amino Acid Density And Energy Levels, Tyler James Clark

Graduate Theses and Dissertations

The responses of two different commercial strains of broilers to diets varying in overall amino acid levels and metabolizable energy levels were observed. Amino acid levels used were 80%, 90%, 100%, 110%, 120%, and 130% of Ross recommended minimum digestable levels of essential amino acids. Energy levels used were either below or above Ross recommended metabolizable energy levels. Diets were fed for 56 days. The two strains were a fast growing broiler strain and a slower growing broiler strain. A selection of birds from each pen was processed at 35, 43, and 56 days of age. Average body weights, cumulative …

In Vivo Periodical Monitoring Of Immune Cell Infiltration In Response To Feathers And Intramuscular Injection Of Ionps Using The Pulp (Dermis) Of Growing Feathers As Test Site Tissue In Chickens, Olfat Taleb Alaamri

Graduate Theses and Dissertations

The applications of nanoparticles are growing, but little is known about their interactions with the immune system as most studies did not use suitable in vivo test systems. The purpose of these studies was to investigate the utility of chicken growing feathers as an in vivo test site for iron oxide nanoparticle (IONP) interactions with the immune system. The first objective of this study was to monitor leukocyte infiltration into the growing feather pulp upon the administration of IONP and IO-mIgG preparations. The second objective was to test the utility of IONPs as vaccine adjuvants by monitoring primary and memory …

The Ability Of Select Probiotics To Reduce Enteric Campylobacter Colonization In Broiler Chickens, Sandip Shrestha

Graduate Theses and Dissertations

Campylobacter is the leading cause of foodborne illness worldwide and is often associated with consumption and/or mishandling of contaminated poultry products. Probiotic use in poultry has been an effective strategy in reducing other enteric foodborne pathogens but not consistently for Campylobacter. As Campylobacter resides and utilizes intestinal mucin for growth, isolates selected on the basis of mucin utilization might be a strategy to screen for efficacious probiotic bacterium. In this study, bacterial isolates demonstrating increased growth rates in mucin, in vitro (trials 1 or 2), or isolates demonstrating a reduction of Campylobacter counts when co-incubated with mucin, in vitro (trials …

Grass Finishing Systems For Lambs, Erin Leigh Smyth

Graduate Theses and Dissertations

There is strong interest in sustainably produced meat. Grass-fed lamb could fulfill this market by reducing off-farm inputs. The objective was to examine the effect of grass-finishing or minimal supplementation on performance of lambs in the southeastern US. Katahdin lambs born in October 2013 and 2014 and February 2014 were weaned in January 2014/2015 and May 2014, respectively. Lambs were blocked by gender (fall; winter included only ram lambs) and randomly assigned to receive no (NON) or grain co-product supplement (SUP; 15% CP) at 0.5% of BW/d. Lambs were rotationally grazed on predominantly grass. Body weight, fecal egg counts (FEC), …

Lidar And Machine Learning Estimation Of Hardwood Forest Biomass In Mountainous And Bottomland Environments, Bowei Xue

Graduate Theses and Dissertations

Light detection and ranging (lidar) has been applied in various forest applications, such as to retrieve forest structural information, to build statistical models for identification of tree species, and to monitor forest growth. However, despite significant progress in these areas, the choice of regression approach and parameter tuning remains an ongoing critical question. This study focused on choosing the right spatial generalization level to transform lidar point clouds to 2D images which can be further processed by mature image processing and pattern recognition approaches. It also compared the prediction ability of popular machine learning algorithms applied to aboveground forest biomass …

Mapping Ancient Baldcypress Forests For Conservation At Black River, North Carolina, Jordan Nichole Burns

Graduate Theses and Dissertations

A few ancient baldcypress-bottomland hardwood forests survive across the southeastern United States in a mosaic of remnant old-growth stands left untouched by extensive logging during the early 20th century. Uncut stands in the Southeast that survived centuries of disturbance following European settlement tended to be too senescent and non-commercial to justify logging. Remnant ancient baldcypress forests at Black River, North Carolina, appear to contain the oldest living trees in eastern North America and The Nature Conservancy has protected several of these stands. However, the full extent of ancient bottomland forests along Black River is not known and many valuable tracts …

Effects Of Crystalline Amino Acid Supplementation Of Reduced Crude Protein (Rcp) Diet On Net Energy Basis On Growing-Finishing Swine, Daniel Cook

Graduate Theses and Dissertations

Barrows and gilts (n=210) were used to test the effects of crystalline amino acid (AA) supplementation of reduced crude protein (RCP) diets formulated on a net energy basis on quality characteristics of the LM from growing-finishing pigs. Pigs were blocked by weight, and pens (3 barrows and 3 gilts/pen) within each block were assigned randomly to either corn-soybean meal diets (C) or 1 of 3 RCP diets and added crystalline AA levels for the dietary treatments during each feeding phase. During the last 3-wk feeding phase, 10 ppm of ractopamine were included in all diets. At slaughter and after a …

Efficacy Of Beta-Resorcylic Acid To Reduce Campylobacter Jejuni In Pre-Harvest And Post-Harvest Poultry, Basanta Raj Wagle

Graduate Theses and Dissertations

Campylobacteriosis is one of the leading foodborne illnesses in United States, and is associated with the consumption of poultry and poultry products. Reducing Campylobacter in these species will reduce the burden of this disease. Unfortunately, most strategies employed to reduce Campylobacter in poultry have either not been successful or produced inconsistent results. One potential control strategy is the use of β-resorcylic acid (BR), a phytophenolic compound classified by the US FDA as "Everything Added to Food in the United States" (EAF 3045) and is therefore deemed safe for consumption. This compounds has antibacterial activity against Salmonella, however, its efficacy to …

Automatic Extraction Of Plots From Geo-Registered Uas Imagery Of Crop Fields With Complex Planting Schemes, Anthony A. Hearst

Open Access Theses

Complex planting schemes are common in experimental crop fields and can make it difficult to extract plots of interest from high-resolution imagery of the fields gathered by Unmanned Aircraft Systems (UAS). This prevents UAS imagery from being applied in High-Throughput Precision Phenotyping and other areas of agricultural research. If the imagery is accurately geo-registered, then it may be possible to extract plots from the imagery based on their map coordinates. To test this approach, a UAS was used to acquire visual imagery of 5 ha of soybean fields containing 6.0 m2 plots in a complex planting scheme. Sixteen artificial targets …

Effects Of Biomass Harvest On Eastern Red-Backed Salamanders, Patrick J. Ruhl

Open Access Theses

In a typical forest harvest, the volume of coarse woody debris (CWD) increases from nonmerchantable material (i.e., tree-tops, limbs, and small-diameter trees) left on the forest floor. Biomass harvesting removes much of this material for bioenergy production. When removed, ecosystem services associated with CWD, such as seedbed substrate, nutrient cycling, and essential wildlife habitat, is reduced. Woodland salamanders have strict microhabitat and soil moisture requirements that make them especially sensitive to timber harvest practices, particularly those that remove CWD, a primary habitat for the group.

I monitored the abundance of Eastern red-backed salamanders ( Plethodon cinereus ) in response to …

Internet Reviews: Iucn Red List Of Threatened Species, John Creech

Library Scholarship

This review evaluates the International Union for Conservation of Nature (IUCN)'s Red List of Threatened Species (available at http://www.iucnredlist.org).