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Adipogenic And Myogenic Stem Cells In Brown Fat: A Study Of Progenitors And Regenerative Capacity, Xin Yang

Open Access Theses

Brown adipose tissue (BAT) utilizes stored lipids to generate heat, therefore reducing body fat content and favoring a leaner body composition. Recent identification of metabolically active BAT in adult humans has sparked broad interests in understanding the developmental origin and postnatal homeostasis of BAT. However, the stem cell population that gives rise to BAT during development and maintains BAT mass at postnatal stage has not been characterized. In addition, whether adult BAT has the capacity to regenerate after injury or to proliferate in response to cold is flargely unknown. Furthermore, although BAT and skeletal muscle are known to share a …

Assessment Of Irrigation Use On Crop Yield And Water Supplies In The Midwestern U.S., Wei-Chih Chen

Open Access Dissertations

Climate plays an important role in many aspects of hydrological and agricultural systems. Temperature and precipitation are usually the main forcing inputs for hydrological and agricultural simulations, while wind effect has generally been neglected in previous research. Wind speed is, however, an important factor for many physical processes, including evaporation from soil, and transpiration from plants. In order to investigate how climate variability impacts agricultural production, there are three hypotheses addressed in this dissertation. Hypothesis 1 is that the representation of changing wind speed will play an important role in the simulation of hydrological processes, and that the effect of …

African Starchy Foods, Gastric Emptying, And Starch Digestion In Malian Stunted Children, Fatimata Cisse

Open Access Dissertations

Starch serves as the main energy source in cereal and tuber-rich diets, and its glycemic response profile has been associated with health-related conditions. Sorghum and millet are known to have relatively low starch digestibility, a potentially desirable property for controlling blood glucose response and providing sustained energy. Gastric emptying rates of traditional sorghum and millet-based African foods of the Sahelian region (couscous, thick and thin porridges made from millet and/or sorghum) were compared to those of non-traditional "modern" foods that are mostly consumed in urban areas using a non-invasive 13C-labelled octanoic acid breath test in healthy volunteers. The obtained results …

Prediction Of Parturition And Dystocia In Holstein-Friesian Cattle, And Cesarean Section In Dystocic Beef Cattle, Wen Han Mark Hiew

Open Access Dissertations

Dystocia is a major problem in the dairy industry as it causes livestock and economic loss. It is more frequently seen in primiparous cattle compared to their multiparous counterparts due to their smaller stature and the slow maturation of pelvic dimensions. In some instances, human intervention of the parturition process is imperative to avoid pain, injury, and mortality of the neonate and the dam. The ability to accurately predict dystocia and the time of parturition will ensure that timely assistance can be given to animals that are of high risk of dystocia.^ The present thesis contains four studies that explore …

Cellular And Molecular Regulation Of Skeletal Muscle Regeneration, Chunhui Jiang

Open Access Dissertations

Skeletal muscle regeneration provides a powerful model to study the cellular and molecular mechanism governing stem cell function since the whole process is mediated by a population of muscle-resident stem cells called satellite cells. The overall aim of this dissertation is to explore the roles of Notch signaling and a novel gene (Bex1) in satellite cell function and skeletal muscle regeneration. ^ The first part of this thesis is to examine how the Notch signaling pathway regulates the satellite cell self-renewal in a disease model. The MDX mouse is a well-established model for Duchenne muscular dystrophy (DMD) and characterized by …

Karyopherin Alpha Subtypes And Porcine Early Stage Embryo Development, Yanfang Li

Open Access Dissertations

Intracellular communication between the nucleus and cytoplasm is critically important for coordinating cellular events during embryogenesis. The karyopherin α/β heterodimer is an intracellular nuclear trafficking system that mediates nuclear import of proteins that bear classical nuclear localization signals (NLSs). Seven karyopherin α subtypes have been identified in the domestic pig, and while each of these karyopherin α subtypes is able to bind to a nuclear localization signal, individual karyopherin α subtypes have been shown to transport specific NLS-bearing proteins. The objective of this study was to determine the developmental requirements of karyopherin α subtypes (KPNAs) during cleavage development in porcine …

Soil Quality And Nitrogen Cycling Dynamics Altered By Fertility Amendments In Intensively Managed Vegetable Production Systems, Matt A. Rudisill

Open Access Dissertations

Fresh market vegetable production in the Midwest U.S. is growing rapidly as a result of increased demand for locally-sourced food. High tunnels are becoming increasingly popular among Midwest vegetable growers as these structures offer many production benefits including season extension. However, vegetables require substantial fertility inputs, particularly nitrogen (N), in order to meet desired levels of productivity, and some fertility management strategies can negatively impact soil and environmental quality. This can be particularly problematic in high tunnels, where longer production periods and modification of the growing environment put these systems at greater risk for soil degradation. Identification of fertility practices …

Us Commodity Support Payments: On Allocation Of Resources And Fairness, Post 1996, Samiul Haque

Open Access Dissertations

This dissertation investigates the effect of US commodity support payment on agricultural producer decisions during the "decoupled" regime. Particular attention is paid to the national optimal output mix, input proportions, and farm level changes in scale operations. While "decoupled" payments were instated to comply with WTO guidelines, where tax payer dollars cannot be spent to alter agricultural outputs and /or on farm input decisions, evidence suggests that such payments are far from being decoupled. At the national level, this dissertation finds evidence for mild labor input using and capital input economizing behavior. Substantial land input economizing behavior and moderate material …

Graduate Students' Motivation To Teach Plant Sciences To K-12 Audiences, Melissa Leiden Welsh

Open Access Dissertations

Graduate students' motivation to share their knowledge and research with K-12 audiences as future scientists is informed by their beliefs and perceived value of science literacy outreach. Graduate training programs in academia integrate outreach teaching components to equip future scientists with a variety of communication skills, which may reflect either a transmission of knowledge to the learner or through engagement with the learner. As such, the education component of the "Partnership for Research and Education in Plant Breeding and Genetics" grant sought to train graduate plant science students ( N = 17) to disseminate their research to K-12 audiences. Graduate …

Uncertainty, Irreversibility, And Investment In Secondgeneration Biofuels, Tanner Joseph Mccarty

Open Access Theses

The present study formalizes and quantifies the importance of uncertainty for investment in a corn-stover based cellulosic biofuel plant. Using a real options model we recover prices of gasoline that would trigger entry into the market and calculate the portion of that entry trigger price required to cover cost and the portion that corresponds to risk premium. We then discuss the effect of managerial flexibility on the entry risk premium and the prices of gasoline that would trigger mothballing, reactivation, and exit. Results show that the risk premium required by plants to enter the second-generation biofuel market is likely to …

Systematics And Evolution Of Leandra S.Str. (Melastomataceae, Miconieae), Marcelo Reginato

Dissertations, Theses, and Capstone Projects

Phylogenetic studies in the Melastomataceae have demonstrated the need of taxonomic rearrangements in the current classification. Melastomes are among the most diverse groups of plants and several cases of known artificial taxa are observed and awaiting further resolution. One example is the Leandra s.str. clade, which includes the majority of the taxa traditionally treated in the genus Leandra. Some attempts have been made to infer the relationships of Leandra s.str., but the sampling in these earlier studies was sparse and the resolution low inside the clade. The main objective here is to propose a comprehensive phylogenetic framework for this group …

Ethnomedical, Ecological And Phytochemical Studies Of The Palauan Flora, Christopher Kitalong

Dissertations, Theses, and Capstone Projects

There has been a serious deterioration of Palauan culture, language and traditional practices over the last century. To promote health and avoid this deterioration of tradition, ecological, ethnobotanical and phytochemical studies have been carried out on the plant Phaleria nisidai Kaneh. (Thymelaeaceae), "Delal a Kar", Palauan for "Mother of Medicine". This study is the first study that sets the foundations for the development of natural Palauan therapeutics, through validation of ethnomedically significant plants. Validations of these plants is done through documenting Palauan plant ethnomedical data; mapping the distribution of Palauan plants on limestone Rock Islands; and analyzing ethnopharmacological and phytochemical …

Bridging The Food Gap: Addressing The Feasibility And Applicability Of Three Key Traditionally Western Food Preservation Techniques To Improving Household Food Security And Reducing Malnutrition In Uganda., Eva K. Baguma

Capstone Collection

Food wastage is the leading cause of food insecurity and malnutrition in the world today. A huge amount of food gets wasted along the food supply chain from the time it is harvested to the time it gets to our plates. A significant amount of the food wasted happens in the home as well as on farms, in restaurants and supermarkets across the globe.

In Sub-Saharan Africa, many families and communities are facing severe food shortages due to lack of electricity for refrigeration, poor storage facilities and limited access to markets.

However for many centuries, different cultures around the world …

Production, Marketing, And Handling Practices To Export Mcintosh Apples To Central American Markets, Mildred L. Alvarado Herrera

Doctoral Dissertations

Latin America offers a marketing opportunity for fresh produce, since many countries are entering into global integration and international trade as part of their portfolio of economic growth. However, to take full advantage of these opportunities, many questions associated with the implementation of marketing approaches, fresh produce quality retention, and profitability need be answered before undertaking this business opportunity. When it comes to developing countries such as those in Central America, and in particular - El Salvador, Honduras, and Guatemala - language, culture, technology, competitiveness, regulations, poverty, and other barriers become challenges to enter these markets successfully. In order to …

Two Spotted Spider Mite (Tetranychus Urticae) Selection To Arabidopsis Thaliana, Huzefa Ratlamwala

Electronic Thesis and Dissertation Repository

Spider mite feeding on A. thaliana induces the production of indole glucosinolates (IGs), plant secondary metabolites that negatively affect mite performance. In this study I conducted selection experiments on A. thaliana with varying levels of IGs, to determine if mites could adapt to IGs and other defense compounds. After 12 months, mites reared on host with IGs performed significantly better on A. thaliana than mites maintained on beans. However, an adaptation cost was detected between selected mite lines and their ancestral host. The qRT-PCR data on different mite lines revealed that the detoxification genes previously identified may only be involved …

Identification And Characterization Of Cysteine Protease Genes In Tobacco For Use In Recombinant Protein Production, Kishor Duwadi

Electronic Thesis and Dissertation Repository

Plants are an attractive host system for pharmaceutical protein production. Many therapeutic proteins have been produced and scaled up in plants at a low cost compared to the conventional microbial and animal based systems. The main technical challenge during this process is to produce sufficient level of proteins in plants. Low yield is generally caused by proteolytic degradation during expression and downstream processing of recombinant proteins. The yield of a human therapeutic protein interleukin (IL) -10 produced in transgenic tobacco leaves was found to be below the critical level, and is potentially due to degradation by tobacco cysteine proteases (CysPs). …

World Wide Diversity Of Phytophthora Capsici, Dylan B. Storey

Doctoral Dissertations

The plant pathogen Phytophthora capsici is a genetically diverse organism that is a global problem. It effects many crops across the Solanacea, Cucurbitacea, andLeguminosea. As a result of the large diversity between individuals (and by extension populations) it has been previously near impossible to make meaningful comparisons between individuals of geographically distinct locations. Here we present the results of applying Next Generation Sequencing (NGS) technologies to a representative panel of isolates. This information and data is further used to demonstrate how this diversity has a functionally relevent effect on a class of proteins responsible for the infectious process. We …

Characteristics Of Agricultural Communications Undergraduate Programs, Morgan Michelle Large

Graduate Theses and Dissertations

This study was designed to characterize agricultural communications undergraduate programs nationwide. A total of 41 undergraduate agricultural communications programs were identified via the National ACT database, Internet searches, and previous academic program research. Objectives included creating an accounting of existing programs, a description of those programs, identifying trends in program demographics, curriculum development and identifying top programs. This study employed a census approach and used a mixed methods design. A mixed-methods survey instrument was used to collect the data. The survey included questions to gain both qualitative and quantitative data to meet this study's objectives. The quantitative data were analyzed …

Assessing Food Policy Options In Asia To Reduce Price Volatility Of Rice Market, Ranjitsinh Mane

Graduate Theses and Dissertations

Rice is a staple food in Asia and its prices at national and international levels are largely influenced by different policy actions of trading countries. The consequence of the 2008 food crisis was food riots and rationing of rice in many nations. The ASEAN Plus Three (APT) countries have adopted an institutional framework called ASEAN Plus Three Emergency Rice Reserves (APTERR) to address food security concerns of ASEAN countries that may arise due to climate change, supply chain disruptions or price speculation in the regional rice market. The RICEFLOW model is used to study the effectiveness of the strategic grain …

Consumer Perceptions And Knowledge Of Genetically Modified Organisms In Belgium: A Case Study Of The Potato Event, Maggie Jo Pruitt

Agricultural Education, Communications and Technology Undergraduate Honors Theses

It is widely known that Europeans have the strongest resistance to genetically modified organisms (GMO). Despite biotechnology advancements in the United States and other countries, European Union (EU) policymakers continue to argue over market-driven GMO regulations. Because humans depend on agriculture for survival, they tend to be concerned with the fundamental risk of combining agricultural production and scientific/technological advancements. In 2011, scientists at a large research institution in Belgium planted a field trial of GM potatoes (during this time GM foods were not in the market). On May 29, an activist group arrived at the field and uprooted the potatoes. …

Application Of Modern Statistical Tools To Solving Contemporary Economic Problems: Evaluation Of The Regional Agricultural Campaign Impact And The Usda Forecasting Efforts, Ran Xie

All Dissertations

The research is comprised with three studies to implement statistical tools for examining two economic issues: the impact of a regional agricultural campaign on participating restaurants and efforts of U.S. Department of Agriculture (USDA) forecasting reports in agricultural commodity markets. The first study examined how various components of the Certified South Carolina campaign are valued by participating restaurants. A choice experiment was conducted to estimate the average willingness to pay (WTP) for each campaign component using a mixed logit model. Three existing campaign components--Labeling, Multimedia Advertising, and the 'Fresh on the Menu' program were found to have a significant positive …

Millennial Alumni Perceptions Of Communications Media Utilized By The Dale Bumpers College Of Agricultural, Food And Life Sciences, Amanda Nicole Anthony

Graduate Theses and Dissertations

Alumni relationship cultivation serves as the foundation of higher education and must be maintained to keep graduates and alma maters connected. To evaluate the success of communications media in reaching recent graduates, classified as Millennials, this study sought to determine Millennial alumni perceptions of media distributed by the Dale Bumpers College of Agricultural, Food and Life Sciences (Bumpers College) from 2012 through 2014. Assessed communications media included The Graduate and AR Culture magazines, The Graduate e-newsletter, tailgate and mocktail party invitations, College website, and social media presences. Active and inactive Millennial alumni (N = 20) responses were gathered through …

Identification And Development Of The Support Needs In Nematology For Arkansas Cooperative Extension Personnel, Mia Gentry

Graduate Theses and Dissertations

County extension agents are vital to the land-grant university system and are responsible for transferring current, research-based knowledge from the university to the community. In-service training allows agents the means to maintain a current, sound knowledge base. Needs identified by leading nematologists led the researcher of this study to assess if nematology education was a topic that warranted in-service training development for Arkansas Cooperative Extension Service (CES) agents. The researcher also assessed agents' comfort level with job related technology. Of the respondents, 67% identified general knowledge of plant parasitic nematodes necessary to meet the needs of their clientele. Findings from …

A Mixed Methods Approach Of Communication Campaign Development And Assessment: Identifying The Needs Of An Audience And Determining The Value In Evaluation, Tara Johnson

Graduate Theses and Dissertations

The two articles presented in this thesis used both quantitative and qualitative research methods to examine two distinct stages of communication campaigns: research and evaluation. In the quantitative study, students (n = 440) at the University of Arkansas were surveyed to determine their perceptions of the Arkansas Water Resources Center (AWRC), water resources, and water issues. A questionnaire was developed from an existing instrument, reviewed by a panel of experts, pilot tested, and revised. The researchers found participants were most aware (M = 3.23, SD = 1.14), concerned (M = 4.07, SD = 0.86), and interested (M = 4.10, SD …

Endophytic Actinomycetes As Potential Agents To Control Common Scab Of Potatoes, Alaxandra A. Goodman

All NMU Master's Theses

Potato marketability and tuber quality can be decreased upon infection by a pathogen, Streptomyces scabies. Current disease control consists of expensive irrigation systems and using hazardous chemicals, which exert limited disease control and are potential hazards to those exposed. Biological control offers a cost effective method for controlling disease. Antibiotic producing Streptomyces have indicated their ability to combat plant diseases. Some Streptomyces species colonize within plant tissues without causing disease symptoms (endophytes). This research sought for the presence of endophytic Steptomyces or closely related species in potato plants that were grown in fields containing pathogen-inhibiting Streptomyces. To establish genus …

Evaluation Of 2,4-D And Dicamba Based Herbicide Programs For Weed Control In Tolerant Soybean, Dwayne Joseph

All Theses

Weeds are the most limiting factor on soybean yields in South Carolina. With their early emergence and rapid growth, weeds compete with crops for resources. The recent evolution of herbicide resistant weeds has made it increasingly difficult for growers to actively control weeds in fields. Glyphosate and ALS-resistant Palmer amaranth (Amaranthus palmeri S. Watson) biotypes have spread rapidly throughout South Carolina, especially in areas where resistance management isn't practiced. In the near future, soybean varieties will be introduced with tolerance to 2,4-D (Dow AgroSciences) and dicamba (Monsanto Company). Field and greenhouse experiments were conducted at Edisto Research and Education Center …

Willingness To Adopt Best Management Practices By Beef Cattle Producers In A Southeastern Tennessee Watershed, Alicia Marie Signore

Masters Theses

Extensive beef cattle farming in the ridge and valley region of East Tennessee suggests that cattle producers could play an important role in improving water quality through the adoption of livestock best management practices (BMPs). This study examines factors influencing willingness to adopt four BMPs—rotational grazing, pasture improvement, stream water crossing, and water tank systems—by beef cattle operations in a southeast Tennessee watershed. Factors examined include farm and farmer characteristics, farmer attitudes, and a hypothetical incentive program encouraging adoption of these practices. Data was collected through a mail survey of 5,150 farmland owners in McMinn, Bradley, and Monroe Counties. Respondents …

Aminocyclopyrachlor Efficacy For Non-Cropland Weed Control, José Javier Vargas Almodóvar

Masters Theses

The production of chemicals for crop protection purposes evolved after World War II with the commercialization of the auxin herbicides 2,4-D and MCPA. Their utility and effectiveness created an interest for North American and European companies to develop and research thousands of agrochemicals available today.

Recently discovered and introduced to the market by DuPont Crop Protection, aminocyclopyrachlor is the first broad spectrum synthetic auxin herbicide in this chemical class, and is structurally similar to the auxin herbicides: aminopyralid, clopyralid and picloram. Aminocyclopyrachlor has activity on broadleaf weed species with limited activity on monocot species. Aminocyclopyrachlor is absorbed via plant roots …

Carbon Sequestration, Carbon Markets, Technical Efficiency And Maize Production Using Conservation Agriculture In Mozambique, Timoteo Eduardo Simone

Masters Theses

Conservation agriculture practices are a promising sustainable farming system being promoted by various organizations in Mozambique. This thesis analyzes the impact of adoption of conservation agriculture practices on maize production technical efficiency, carbon sequestration and farmer income. The technical efficiency estimation utilizes data from a household survey conducted in Manica and Tete provinces of Mozambique. Soil carbon simulations use information from various sources including the household survey, European Energy markets and local meteorological data from the National Oceanic and Atmospheric Administration.

The second chapter of the thesis evaluates the technical efficiency of maize production using conservation agriculture practices. This section …

Investigating The Effect(S) Of Contrasting Nitrogen (N), Phosphorus (P), And Potassium (K) Fertilizer Rates On Cassava Tuber Yield And Quality And Maize Grain Yield In Southern Africa, Ivan Bernardo Cuvaca

Masters Theses

Fertilizer is a major limiting factor to agriculture in southern Africa (SA). Coupled with this is lack of appropriate fertilizer recommendation rates for high productivity in existing agricultural systems. Field experiments were conducted to determine nitrogen (N), phosphorus (P), and potassium (K) fertilizer rates for high cassava tuber yield and quality for the coastal semiarid Dondo District of Mozambique, and high maize grain yields for both vertisol and inceptisol of Maphutseng in Lesotho. In general, the results showed that cassava tuber yield, cassava tuber quality as measured by tuber starch content, and maize grain yield were significantly increased by fertilizer …