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Essays On Malawian Agriculture: Micro-Level Welfare Impacts Of Agricultural Productivity; Profitability Of Fertilizer Use; And Targeting Of Fertilizer Subsidy Programs, Francis Addeah Darko Dec 2016

Essays On Malawian Agriculture: Micro-Level Welfare Impacts Of Agricultural Productivity; Profitability Of Fertilizer Use; And Targeting Of Fertilizer Subsidy Programs, Francis Addeah Darko

Open Access Dissertations

This dissertation comprises of three essays that address different aspects of agriculture in Malawi using a two-wave panel data collected by the National Statistical Office of Malawi with support from the World Bank Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA) program. Each essay stands alone as an independent study because of differences in research questions and the methodologies used in addressing the questions.

The first essay analyzes the micro-level welfare impacts of agricultural productivity. Welfare is measured by various dimensions of poverty and food insecurity; and agricultural productivity is measured by maize yield and value of crop output ...


Quantifying Terrestrial Ecosystem Carbon Dynamics With Mechanistically-Based Biogeochemistry Models And In Situ And Remotely Sensed Data, Shaoqing Liu Dec 2016

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 ...


Reflexivity: A First Demonstration, Melissa Jane Swisher Aug 2016

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 ...


The Effects Of Including Almonds In An Energy-Restricted Diet On Weight, Body Composition, Visceral Adipose Tissue, Blood Pressure And Cognitive Function, Jaapna Dhillon Aug 2016

The Effects Of Including Almonds In An Energy-Restricted Diet On Weight, Body Composition, Visceral Adipose Tissue, Blood Pressure And Cognitive Function, Jaapna Dhillon

Open Access Dissertations

Inclusion of almonds in an energy restricted diet has been reported to enhance or have no effect on weight loss. Their effects specifically on visceral fat stores during energy restriction have not been widely examined. Additionally, almond consumption has been associated with reduced blood pressure, but whether this is linked to or is independent of changes of body composition has not been examined. Moreover, almond consumption during energy restriction may be an effective strategy for reversing the negative effects of dieting on cognitive performance. The unique nutrient profile of almonds also has the potential to influence cognitive function post-prandially. The ...


The Effect Of Voluntary Binge Caffeine And Ethanol Coexposure On Neurobehavioral Sensitivity To Cocaine In Male C57bl/6j Mice, Brandon M. Fritz Apr 2016

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 ...


Trade And Agriculture Policy Options To Improve The Wheat Subsector In Afghanistan, Ghulam Hazrat Halimi Apr 2016

Trade And Agriculture Policy Options To Improve The Wheat Subsector In Afghanistan, Ghulam Hazrat Halimi

Open Access Dissertations

In Afghanistan wheat availability is important for national food security as it is the key staple food, accounting for over half of calorie intake. The country has imported on average 32% of its wheat consumption over the period 2000-2015, primarily from Pakistan and Kazakhstan. Since domestic production is volatile, consumer well-being depends on access to international markets.

Pakistan, a key supplier of wheat and flour to Afghanistan, has not been a reliable source for Afghanistan to meet its wheat deficit. Pakistan subsidizes and stabilizes its wheat production, and this benefited Afghan consumers before 2008. Pakistan restricted wheat and flour exports ...


Elucidation Of Pharmacologically Manipulated Responding In The Delay Discounting Task In High Alcohol Preferring Mice, Meredith Halcomb Apr 2015

Elucidation Of Pharmacologically Manipulated Responding In The Delay Discounting Task In High Alcohol Preferring Mice, Meredith Halcomb

Open Access Dissertations

Impulsive behavior is the hallmark of many psychopathologies. Uncovering the neurobiological mechanisms driving impulsivity is paramount in the development of through the delay discounting (DD) task in both human and animal models. The present study is an examination of the predictive validity of the two primary types of DD procedures in animals, the Adjusting Amounts (AA) and within session Increasing Delays (ID) tasks. Methods:Subjects were administered either1.25 mg/kg d-amphetamine (AMP), 1.5 g/kg ethanol (EtOH) or saline and tested in either the AA or ID method for 15 days to evaluate drug effects on impulsive behavior ...


Communication, Home Bias And Social Capital, Sharon Raszap Skorbiansky Apr 2015

Communication, Home Bias And Social Capital, Sharon Raszap Skorbiansky

Open Access Dissertations

This dissertation consists of three essays on the effects of communication, home bias and social capital. The first study analyzes three different laboratory treatments that determine if policies that introduce and improve communication are beneficial to a market. The control treatment has no communication. Then, two different types of communication mechanisms are introduced: cheap communication, where subjects are able to lie, and truthful communication, where only honest messages may be sent. The results demonstrate that truthful communication dramatically improves subjects' ability to trade efficiently, ultimately leading to higher social surplus and lower income inequalities. Cheap communication does not produce the ...


The Use Of Oral History And Narrative Research In Broadening The Historical Foundation Of The Agricultural Communication Field, Natalie L Federer Jan 2015

The Use Of Oral History And Narrative Research In Broadening The Historical Foundation Of The Agricultural Communication Field, Natalie L Federer

Open Access Dissertations

The historical foundation of the agricultural communication community (consisting of both academics and the profession) is shallow and void of humanistic perspective, and there is a minimal amount of historical content that focuses on academic and professional history. The need to explore and interpret historical dimensions of this field is vital to further development of the discipline as an academic and professional field. Oral history was utilized to capture and preserve the interview content from a small sample of agricultural communication and Extension professionals and faculty while narrative research, interpretative theory, and constructivism were utilized to further understand and interpret ...


Associated Behavioral, Genetic, And Gene Expression Variation With Alternative Life History Tactics In Salmonid Fishes, Ashley Chin-Baarstad Oct 2014

Associated Behavioral, Genetic, And Gene Expression Variation With Alternative Life History Tactics In Salmonid Fishes, Ashley Chin-Baarstad

Open Access Dissertations

Individual differences in behavior can have potential fitness consequences and often reflect underlying genetic variation. My research focuses on three objectives related to individual level variation: 1) evaluating the innate behavioral variation within and between individuals, families, and progeny of different life-history types across time; 2) testing for differences in gene expression within the brain associated with this behavioral variation; and 3) using genetic polymorphisms to test for associations with ecotype, as well as population structure, in polymorphic populations. First, we evaluated the variation in a suite of ecologically relevant behaviors across time in juvenile progeny produced from crosses within ...


Role Of Group Ii Metabotropic Glutamate Receptor Subtype 2 (Mglur2) In Appetitive And Consummatory Aspects Of Ethanol Reinforcement, Kyle Allyson Windisch Oct 2014

Role Of Group Ii Metabotropic Glutamate Receptor Subtype 2 (Mglur2) In Appetitive And Consummatory Aspects Of Ethanol Reinforcement, Kyle Allyson Windisch

Open Access Dissertations

Background: Group II metabotropic glutamate receptors (mGluR2/3) are predominately presynaptically located Gi/o coupled receptors that are highly expressed in the cortex, nucleus accumbens, amygdala, and hippocampus. Previous studies suggest that group II mGluRs are involved in regulating ethanol (EtOH) consumption and seeking following extinction (Backstrom and Hyytia, 2005; Kufahl, et al., 2011). The sipper tube model, which allows for procedural separation of seeking and consumption, was used to further clarify the role of mGluR2/3 in EtOH-seeking and consumption. The non-selective group II mGluR agonist LY379268 (LY37) and selective mGluR2 positive allosteric modulator (PAM) BINA were used ...


The Role Of Adiponectin And The Adipocyte In Energy Metabolism And Inflammation, Sheila Kay Jacobi Oct 2014

The Role Of Adiponectin And The Adipocyte In Energy Metabolism And Inflammation, Sheila Kay Jacobi

Open Access Dissertations

A series of experiments were conducted to characterize the autocrine role of adiponectin in modulating fatty acid metabolism and inflammation in the pig. In the first study, we cloned and sequenced the porcine adiponectin open reading frame and evaluated the regulation of adiponectin, in vitro and in vivo. The porcine sequence shares approximately 88, 86, 85 and 83% homology with the dog, human, cow and mouse adiponectin, respectively, and 79–83% similarity with dog, human, cow and mouse proteins at the amino acid level, based on the translated porcine sequence and GenBank submissions for the other species. Analysis of serum ...


Multidimensional Approach To Comparative Avian Visual Systems, Bret Alan Moore Oct 2014

Multidimensional Approach To Comparative Avian Visual Systems, Bret Alan Moore

Open Access Dissertations

Since the birth of visual ecology, comparative studies on how birds see their world have been limited to a small number of species and tended to focus on a single visual trait. This approach has constrained our ability to understand the diversity and evolution of the avian visual system. The goal of this dissertation was to characterize multiple visual dimensions on bird groups that are highly speciouse (e.g., Passeriformes), and test some hypotheses and predictions, using modern comparative tools, on the relationship between different visual traits and their association with visual information sampling behaviors. First, I developed a novel ...


Energy Production, Distribution, And Pollution Controls: Combining Engineering And Economic Analysis To Enhance Efficiency And Policy Design, David F. Perkis Oct 2014

Energy Production, Distribution, And Pollution Controls: Combining Engineering And Economic Analysis To Enhance Efficiency And Policy Design, David F. Perkis

Open Access Dissertations

Three published articles are presented which focus on enhancing various aspects of the energy supply chain. While each paper adopts a different methodology, all three combine engineering data and/or techniques with economic analysis to improve efficiency or policy design within energy markets. ^ The first paper combines a chemical engineering plant design model with an economic assessment of product enhancements within an ethanol production facility. While a new chemical process is shown to achieve greater ethanol yields, the animal feed by-products are denatured and decrease in value due to the degradation of a key nutritional amino acid. Overall, yield increases ...


Impacts And Feasibility Of The Us And The Eu Sustainability Criteria On Existing Land-Use Practices, Krissana Treesilvattanakul Oct 2013

Impacts And Feasibility Of The Us And The Eu Sustainability Criteria On Existing Land-Use Practices, Krissana Treesilvattanakul

Open Access Dissertations

Several studies have examined the land use and economic consequences of national and multi-national biofuel policies. They explored the impacts of biofuels mandates mainly based on the quantitative biofuel targets. However, the recently updated renewable policies of the United States and the European Union, which are the US Renewable Fuel Standard (RFS) and EU Directive 2009/28 of the Renewable Energy Directive (RED) both place restrictions on land that can be used to produce biofuel, and these restrictions are generally known as sustainability criteria. This research aims to determine to what extent sustainability criteria are actually binding; that is, would ...


Welfare Impacts Of False Codling Moth Threatening California Oranges, Azza Mohamed Kamal Ahmed Mohamed Oct 2013

Welfare Impacts Of False Codling Moth Threatening California Oranges, Azza Mohamed Kamal Ahmed Mohamed

Open Access Dissertations

Welfare impacts of alternative pest management strategies of False Codling Moth (FCM) threatening California's oranges are examined. Different economic agents along the supply chain of fresh oranges and orange products in the United States are considered, including consumers, retailers, wholesalers, and growers. A partial equilibrium dynamic framework that accounts for supply response from the other US orange producing states is developed. Data for supply shocks (orange yield losses and control costs) are obtained from the Animal and Plant Health Inspection Service of the United States Department of Agriculture (APHIS).

FCM is not presently in the United States. If introduced ...


The Structure Of Consciousness, Lowell Keith Friesen Sep 2013

The Structure Of Consciousness, Lowell Keith Friesen

Open Access Dissertations

In this dissertation, I examine the nature and structure of consciousness. Conscious experience is often said to be phenomenally unified, and subjects of consciousness are often self-conscious. I ask whether these features necessarily accompany conscious experience. Is it necessarily the case, for instance, that all of a conscious subject's experiences at a time are phenomenally unified? And is it necessarily the case that subjects of consciousness are self-conscious whenever they are conscious? I argue that the answer to the former is affirmative and the latter negative.

In the first chapter, I set the stage by distinguishing phenomenal unity from ...


Visuospatial Reasoning In Toddlers: A Correlational Study Of Door Task Performance, Iris Louella Price May 2009

Visuospatial Reasoning In Toddlers: A Correlational Study Of Door Task Performance, Iris Louella Price

Open Access Dissertations

Previous research using violation-of-expectation paradigms suggests that very young infants have a good understanding of unobserved physical events. Yet toddlers appear to lack this knowledge when confronted with the door task, a visuospatial reasoning task which parallels ones used in the habituation/looking time studies. Many studies have been conducted in an effort to determine why toddlers perform poorly on the door task yet the answer remains unclear. The current study used a correlational approach to investigate door task performance from both psychological (executive function), and neuroscience (prefrontal cortex) perspectives. Children between the ages of 2 ½ - 3 years were ...