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Full-Text Articles in Life Sciences

Relationships Between Landscape Factors And Crayfish Density And The Interacting Effects Of Grazing And Increased Sedimentation On Algal Biomass, Katheryn Haley Rose Dec 2013

Relationships Between Landscape Factors And Crayfish Density And The Interacting Effects Of Grazing And Increased Sedimentation On Algal Biomass, Katheryn Haley Rose

Theses and Dissertations

In recent years in the United States there has been a rapid expansion in anthropogenic sources of sediment in streams including construction, agriculture, and drilling for natural gas. Potential effects land disturbance associated with activities from natural gas development on aquatic biota in surrounding streams have not yet been well documented. An increase in inorganic sediment in streams can be detrimental to organisms through a variety of mechanisms including alteration of dominant substrate type, higher turbidity resulting in lower visibility, and burial of food resources such as algae and detritus. Increasing sedimentation in stream environments through anthropogenic disturbance is a ...


Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green Dec 2013

Greater Sage-Grouse (Centrocercus Urophasianus) Habitat Selection In Northwestern Wyoming And Stable Isotope Analysis Of Fecal Material, Andrea Renee Green

Theses and Dissertations

Dramatic range-wide declines in Greater Sage-Grouse populations have prompted efforts to determine habitat characteristics that are selected by sage-grouse for foraging, nesting and brood-rearing areas in an effort to conserve this species. Managers at Heart Mountain and Y U Bench in northwestern Wyoming expressed the need to quantify various habitat characteristics and to determine key use areas at both study sites. Data were collected on a variety of habitat variables in spots selected by grouse for foraging, nesting, and brood-rearing activities. These variables were compared to the same variables measured at random points at both study sites. Significant differences existed ...


Post-Exercise And Post-Recovery Blood Lactate In Peripheral Arterial Disease, Rebecca Kate Roderick Dec 2013

Post-Exercise And Post-Recovery Blood Lactate In Peripheral Arterial Disease, Rebecca Kate Roderick

Theses and Dissertations

The purpose of this study was to observe how the presence of peripheral arterial disease affects the level of post-exercise blood lactate and post-recovery blood lactate during and following the six-minute walk test (6MWT). The 6MWT was administered to 49 participants (33 classified as Non-PAD and 16 classified as PAD) over the age of 50 with no uncontrolled cardiovascular or metabolic diseases or a cardiovascular event in the previous 6 months. Results demonstrated that no significant statistical difference exists between the presence of PAD and resting blood lactate (F = 0.86, p = .36), post-exercise blood lactate (F= 0.48, p ...


Identification Of Biomarkers Associated With Ascites Incidence In Broilers, Kaylee Rowland Dec 2013

Identification Of Biomarkers Associated With Ascites Incidence In Broilers, Kaylee Rowland

Theses and Dissertations

Poultry is key in genetic research due to breeding feasibility, relatively short generation interval, and distinct phenotypes. It is estimated that 8% of broiler deaths annually can be attributed to ascites, an economically important disease that has been challenging the industry for the past 2 decades. Genetically selected ascites resistant (RES) and susceptible (SUS) chicken lines have been established and maintained by the University of Arkansas, Fayetteville. Intensive research efforts have been made to reveal physiological and biochemical characteristics for the incidence of ascites. Since the whole genome of the major ancestral chicken, the Red Jungle Fowl, has been sequenced ...


Congruent And Incongruent Effects Of Ethnic Music On Ethnic Menu Item Selection, Ryan David Muniz Dec 2013

Congruent And Incongruent Effects Of Ethnic Music On Ethnic Menu Item Selection, Ryan David Muniz

Theses and Dissertations

This study investigated what impact ethnic music had on ethnic menu item selection. College students were randomly divided into three groups and listened to one randomly assigned sound treatment in sensory booths. Three hundred and five participants completed the questionnaire with measures of expected price value and willingness to pay value. One of the groups listened to an Italian folk music, the second group listened to a Thai folk music, and the third group listened to a restaurant background noise in order to examine if the music will impact each participant menu items selection and perceived price values. The result ...


Evaluation Of Shake Weight Protocol In Senior Populations, Isaac F. Cook Dec 2013

Evaluation Of Shake Weight Protocol In Senior Populations, Isaac F. Cook

Theses and Dissertations

The Shake Weight® (SW®) is designed to improve muscular fitness in a quick and inexpensive way. This study aimed to determine if the SW® was an effective tool at improving muscular fitness, body composition, and bone mineral density (BMD) in post-menopausal women. Participants were 17 healthy, post-menopausal women from aMidwestern University and divided into two training (SW® and HIT) interventions that lasted 10 weeks. HIT participants performed three sets of 8 repetitions at 80% of their estimated 1RM for the chest press, leg press, lat pulldown, and seated row. SW® participants performed the exercises prescribed by the SW® manufacturer. Changes ...


Sugar And Rice Trade Between The United States And Cuba Trade Potential And Welfare Analysis, Fabian Bloechl Dec 2013

Sugar And Rice Trade Between The United States And Cuba Trade Potential And Welfare Analysis, Fabian Bloechl

Theses and Dissertations

After the resignation of President Fidel Castro and forty-five years of the U.S.-trade embargo, the political environment between Cuba and the United States is expected to change. With the Trade Sanction Reform and Export Enhancement Act in 2000, trade sanctions were eased for a while. Future trade between both countries would increase the welfare in both countries. This Thesis has the approach to look at the impacts on the commodities of rice and sugar, and the trade sanctions between the United States and Cuba.

Cuba is a net importer of its food supply; therefore, agriculture and food trade ...


Ecology And Structure Of Black Bear (Ursus Americanus) Populations In The Interior Highlands Of Arkansas, Thea Vandervelde Kristensen Aug 2013

Ecology And Structure Of Black Bear (Ursus Americanus) Populations In The Interior Highlands Of Arkansas, Thea Vandervelde Kristensen

Theses and Dissertations

In the Interior Highlands of Arkansas, Missouri, and Oklahoma, over-harvest, extensive logging, and reductions of habitat availability by other means contributed to the decline of black bears (Ursus americanus). Bears were extirpated from the majority of the region by the 1940's Oklahoma by 1915 and from Missouri by 1931. From 1958-1968, the Arkansas Game and Fish Commission undertook a reintroduction to the Ouachita and the Ozark National Forests in Arkansas. The successful growth and expansion of the released population caused these efforts to be considered one of the most successful reintroductions of carnivores. In this dissertation, I sought to ...


The Interactive Effects Of Multiple Stressors On Lithobates Catesbeianus And Anaxyrus Americanus, Matthew Kyle Holden Aug 2013

The Interactive Effects Of Multiple Stressors On Lithobates Catesbeianus And Anaxyrus Americanus, Matthew Kyle Holden

Theses and Dissertations

Amphibian populations worldwide have experienced dramatic declines, and many species have already become locally, regionally, or globally extirpated with thousands more being threatened with extinction. These declines have occurred more rapidly in amphibians than any other group of vertebrates, which is especially concerning to scientists because amphibians serve as indicator species of overall environmental health. Major causes for amphibian declines are discussed in Chapter 1 and include: habitat modification and destruction, commercial over-exploitation, introduced species, environmental contaminants, global climate change, and infectious diseases.

Chapter 2 discusses the major research aspects of the thesis by examining the interactive effects of multiple ...


Evaluating Economic And Environmental Impacts Of Changing Herd Sire Genetics On Arkansas Cow-Calf Operations, Daniel Keeton Aug 2013

Evaluating Economic And Environmental Impacts Of Changing Herd Sire Genetics On Arkansas Cow-Calf Operations, Daniel Keeton

Theses and Dissertations

This research looks at impacts of changing sires, and thus bull genetics, on cow-calf operations of varying land and herd sizes in the state of Arkansas. A 2012 Across-Breed EPD table, adjusted to the Angus breed, was used to estimate breed sire effects on birth weight and weaning weight of the herd's offspring (Kuehn and Thallman 2012a). Together with modified animal performance, the use of 2012 and most recent five- and ten- year Arkansas state average prices, allowed the evaluation of changing herd sires by accounting for breed type and hide color differences in prices. Using a spreadsheet tool ...


The Impact Of Parent Education On Parental Feeding Practices, Larra Kolby Brawley Aug 2013

The Impact Of Parent Education On Parental Feeding Practices, Larra Kolby Brawley

Theses and Dissertations

This research looked at the potential impact that parent education may have on the feeding practices of parents of young children. Since eating behaviors are a national concern for both children and adults, it's important to examine how we can create not just healthier children but, as a result, healthier adults. This study utilized an intervention that was an adapted version of a healthy eating curriculum created by Sesame Workshop and the California WIC association with the intention of improving parental feeding practices through a behavior-based approach. Previous research with this curriculum has addressed only low-income populations, with a ...


Turpentine Creek: Arkansas' Refuge, Jacob Paul Bain Aug 2013

Turpentine Creek: Arkansas' Refuge, Jacob Paul Bain

Theses and Dissertations

The goal of this Master's thesis film project was twofold. First, I wanted to explore the problem, huge but relatively unknown, of the ownership of exotic pets in the United States of America. Second, in conjunction with that problem, I wanted to see how Turpentine Creek Wildlife Refuge (TCWR) approached it and what, as an organization, they do to help resolve this problem locally and nationally. In turn, the film also provides an in-depth look at a very unique refuge in the state of Arkansas. Using my own equipment, I shot and edited a short-form documentary about TCWR. The ...


Evaluation Of Water Sanitation Options For Poultry Production, Pramir Maharjan Aug 2013

Evaluation Of Water Sanitation Options For Poultry Production, Pramir Maharjan

Theses and Dissertations

An evaluation of poultry farm water supplies was conducted to determine the value and impact of water system sanitation practices in commercial broiler houses on microbial levels. Water line cleaning between flocks using concentrated disinfectant solution before placing chicks reduced biofilms retained in the lines to a safe level. Occasional microbial surges were noticed during different points of flock grow-out period even when daily water sanitation was present indicating water is highly susceptible to microbial contamination. However, the daily water sanitation practice controlled the occasional microbial surges in water from sustaining and kept drinking water to a microbiologically acceptable level ...


Genetic Structure Of The Copperhead (Viperidae: Agkistrodon Contortrix Mokasen) At Its Most Northern Distribution, Brenna Aaren Levine May 2013

Genetic Structure Of The Copperhead (Viperidae: Agkistrodon Contortrix Mokasen) At Its Most Northern Distribution, Brenna Aaren Levine

Theses and Dissertations

The focus of molecular studies in North American pitvipers has been on species that warrant conservation concern, such as Timber (Crotalus horridus) and Massasauga rattlesnakes (Sistrurus catenatus). Scant effort has been directed towards the molecular ecology of the Copperhead (Agkistrodon contortrix), other than to evaluate male reproduction in a laboratory setting and phylogenetic history. Thus, employing DNA-based molecular techniques to study the natural history of A. contortrix will broaden our knowledge of molecular ecology in North American pitvipers, and particularly in a non-threatened species that can serve as a surrogate for threatened and endangered taxa. Our study will also provide ...


Measuring The Energy Required To Dry Rice In Commercial Rice Dryers, Maria Alejandra Billiris May 2013

Measuring The Energy Required To Dry Rice In Commercial Rice Dryers, Maria Alejandra Billiris

Theses and Dissertations

The objective of this research was to quantify and assess the energy use and efficiency of commercial cross-flow dryers when drying rice using a range of drying and ambient conditions. First, equations that predict the theoretical energy required to dry rice from any given initial moisture content to a desired final moisture content were developed for several rice cultivars using a semi-theoretical approach to obtain a basis for comparison to calculate energy efficiency. Theoretical energy requirements, expressed as the energy required per unit mass of water removed, increased exponentially as initial moisture content decreased. Additionally, medium-grains required more energy to ...


Cost-Benefit Analysis Of Farmer Training In Ghanaian Cocoa Farming, Michael Norton May 2013

Cost-Benefit Analysis Of Farmer Training In Ghanaian Cocoa Farming, Michael Norton

Agricultural Economics and Agribusiness Undergraduate Honors Theses

While billions of dollars flow into low-income countries each year to help alleviate poverty, assessing the effectiveness of these dollars is a challenging task. The literature is rich in studies that measure the benefits of rural development programs. However, many of these studies lack a temporal dimension because they measure cost and benefits for only capital investments and for only a single, static year, while not accounting for skill enhancement. By only measuring net producer benefits during the life of the development program, the cost-benefit analyses (CBA) may not truly capture the full net benefits of a given program. In ...


Physio-Chemical And Sensory Properties Of A Nutrient-Fortified Extruded Product, Tajudini Lassissi Akande May 2013

Physio-Chemical And Sensory Properties Of A Nutrient-Fortified Extruded Product, Tajudini Lassissi Akande

Theses and Dissertations

Protein malnutrition is responsible for half the deaths of children under the age of five each year in developing countries. More than 4%, 26%, and 70% of children with protein malnutrition live in Latin America/the Caribbean, Africa, and Asia, respectively. The objective of this research was to develop a novel snack made with millet, black eye bean (from Niger Republic), and rice flour fortified with soybean meal protein using extrusion technology. Proximate analysis of the four flours was carried out to determine their chemical composition. Central composite design (CCD) was used to obtain best extrusion conditions to develop a ...


Genetic Analysis Of The Promoter Region Of The Serotonin Receptor 5ht2b And Its Contribution To Pulmonary Hypertension Syndrome In Broiler-Type Chickens, Khaloud Awada Alzahrani May 2013

Genetic Analysis Of The Promoter Region Of The Serotonin Receptor 5ht2b And Its Contribution To Pulmonary Hypertension Syndrome In Broiler-Type Chickens, Khaloud Awada Alzahrani

Theses and Dissertations

Pulmonary Arterial Hypertension (PAH) is a sever disorder characterized by high pulmonary artery pressure and pulmonary vascular resistance along with specific histological changes. Idiopathic PAH is a human disease of unknown origin that showed common characteristics to PHS/ascites in chicken. PHS/ascites is a condition found in broilers causing right ventricular hypertrophy, valvular insufficiency, increased venous pressure, variable liver changes, accumulation of fluids in the abdominal cavity, and finally lung and heart failure. Currently, there is no acceptable animal model for human PAH. Our group has been validating the chicken as the medical animal model for human PAH, thus ...


Local Food And Agriculture Awareness: The Literacy Of Local Produce And Agriculture In Northwest Arkansas, Kyle Colton Flynn May 2013

Local Food And Agriculture Awareness: The Literacy Of Local Produce And Agriculture In Northwest Arkansas, Kyle Colton Flynn

Theses and Dissertations

The Center for Disease Control and Prevention (CDC) suggests that adolescents and children, both male and female, are failing to meet the daily fruit and vegetable consumption requirements (Kim et al., 2011; Upton et al., 2012; Harris et al., 2012). Other studies have shown that with increased exposure and availability of produce, students (K-5) tend to consume more fruits and vegetables (Cullen et al., 2009; Evans et al., 2012). The purpose of this study is to identify whether Northwest Arkansas eleventh grade high school students possess experience and knowledge of local produce and agriculture. Out of 1054 students enrolled at ...


Effects Of Ergot Alkaloids And Bovine Bodily Fluids On Cytochrome P450 Activity, Nicholas Scott Ezell May 2013

Effects Of Ergot Alkaloids And Bovine Bodily Fluids On Cytochrome P450 Activity, Nicholas Scott Ezell

Theses and Dissertations

This thesis evaluates the PromegaTM P450-Glo assay (PromegaTM V9800) as a tool for quantifying ergot alkaloid concentration. Current techniques used for detection of ergot alkaloids are slow and expensive, do not detect all ergot alkaloids, or are not effective on bovine bodily fluids. The first study was conducted to determine effects of commercial ergot alkaloids (n = 6; 0 - 400 μM) on the PromegaTM P450-Glo assay. Cytochrome P450 (CYP450) activity in assay had a differential response to each ergot alkaloid and concentration. As concentrations of ergotamine, dihydroergotamine, ergocornine, and ergocryptine increased CYP450 activity was inhibited (P < 0.05). Increases in ergonovine and pergolide concentration did not affect (P > 0.1 ...


Effects Of Using Canola Meal As A Protein Source In Broiler Diets, Charles Danny Bradley Jr May 2013

Effects Of Using Canola Meal As A Protein Source In Broiler Diets, Charles Danny Bradley Jr

Theses and Dissertations

Six experiments were conducted to evaluate the response of broilers fed canola meal. Experiment 1 assessed performance and carcass yields when broilers were fed various combinations of canola and soybean meal in nutritionally balanced diets based on digestible amino acid values. The results suggested that canola meal can be used in isocaloric diets as a partial replacement for Soybean meal.

Experiment 2 assessed broiler performance and carcass yields when using various levels of canola meal in broiler diets with a constant level of supplemental poultry oil. The resulting data suggested when diets are formulated with a constant level of supplemental ...