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Full-Text Articles in Life Sciences

Evaluating The Physical Welfare Of Dogs In Commercial Breeding Facilities In The United States, Moriah J. Hurt Aug 2016

Evaluating The Physical Welfare Of Dogs In Commercial Breeding Facilities In The United States, Moriah J. Hurt

Open Access Theses

Despite high levels of public concern, the state of commercial breeding (CB) dog welfare is largely unknown. Therefore, this study aimed to characterize the physical welfare of dogs in CB facilities and their environment in Indiana. This study specifically aimed 1) to characterize dog foot health in CB facilities as a function of the length of time dogs were housed on a given flooring substrate, 2) to characterize visual dog body cleanliness and visual kennel cleanliness as a function of the flooring substrate, 3) to determine the efficacy of kennel cleaning procedures and 4) to characterize the dog dental and …


The Effect Of Climate Change On The Economics Of Conservation Tillage: A Study Based On Field Experiments In Indiana, Whitney Hodde Aug 2016

The Effect Of Climate Change On The Economics Of Conservation Tillage: A Study Based On Field Experiments In Indiana, Whitney Hodde

Open Access Theses

This study evaluates the economics of conservation tillage (chisel till and no till) and examines how climate change will likely affect it. We use data from long-term experimental plots in Indiana to estimate how corn and soybean yields respond to weather patterns under alternative tillage practices. Yield functions are coupled with random draws of weather variables to construct distributions describing the probability that conservation tillage will result in higher profits than more intensive tillage, under current and future climatic regimes. Results suggest that, in our study area, projected climate change will make conservation tillage more attractive.


Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller Aug 2016

Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller

Open Access Theses

Flawed U.S. federal regulation of chemicals has resulted in a materials market that undervalues human and environmental health in favor of the more traditional attributes of price, performance and aesthetics. In the building products industry, global, dynamic supply chains and proprietary information concerns further complicate the task of assessing the material health of products.

Voluntary material health programs in the green building industry are intended to incentivize the manufacture and selection of safer products by getting companies to gather and assess ingredient, hazard and risk information from their supply chain. Building product manufacturers considered early adopters of the main material …


The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini Aug 2016

The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini

Open Access Theses

Natural systems are home to a multitude of natural and anthropogenic stressors, which draw an array of effects on ecological communities. While these effects have been investigated individually, it is important, given the routine co-occurrence of these stressors, to understand their interactive effects. Pesticide exposure and infectious disease are two common, co-occurring stressors that each have documented detrimental effects on species and, as evidence suggests, may have interactive effects. Moreover, existing research suggests that these interactive effects are highly context dependent, eliciting different results based on species, disease agent, toxin, and environment. Given the variability with which species may experience …


An Assessment Of The Competitive Ability Of Oak Species In The Central Hardwood Region Using Both Pre-Harvest Treatment Data And Stem Analysis Techniques, Robert William Edward Quackenbush Aug 2016

An Assessment Of The Competitive Ability Of Oak Species In The Central Hardwood Region Using Both Pre-Harvest Treatment Data And Stem Analysis Techniques, Robert William Edward Quackenbush

Open Access Theses

The density of advance regeneration of oak species has been in decline across the Central Hardwood Region (CHR) for the past 50 years. This phenomenon has been accredited to many different factors, ranging from predation and browse by wildlife, to human induced changes in the environment which include massive clearcutting, land use change from forest to agriculture, and suppression of fires which played an intricate role in the development of oak systems across the CHR. The objectives of this research project were to compare densities of oak advance regeneration across two different environmental gradients within the CHR, in particular the …


Mergers And Acquisitions In Food And Agribusiness: Returns, Drivers, And Long Run Performance, Josiah M. Ringelberg Aug 2016

Mergers And Acquisitions In Food And Agribusiness: Returns, Drivers, And Long Run Performance, Josiah M. Ringelberg

Open Access Theses

Food and agribusiness in the U.S is a dynamic and ever changing business. The industry has seen booms and busts, considerable consolidation, and continued globalization in the past few decades. Businesses operating within its sectors have had to demonstrate flexibility and adaptability as the industry’s landscape consolidates at the consumer, supplier, and producer level. One strategy companies have used to grow and position themselves throughout years of industry consolidation has been merger and acquisition (M&A) transactions.

During the eleven years from 1985 and 1995, the food industry was listed in the top 10 M&A most active industries ten times. It …


High School Students' Motivations And Views Of Agriculture And Agricultural Careers Upon Completion Of A Pre-College Program, Andrea K. Scherer Aug 2016

High School Students' Motivations And Views Of Agriculture And Agricultural Careers Upon Completion Of A Pre-College Program, Andrea K. Scherer

Open Access Theses

Pre-college summer residential experiences hosted by a College of Agriculture have the potential to expose high school students to new career opportunities and fields of study that they may not have considered, and may influence agricultural literacy, perceptions of agriculture, and interest in agriculture. Engaging these students is important for meeting the demand for more students graduating with agriculture degrees prepared to solve 21st century challenges. The purpose of this study was to explore and describe the outcomes of two separate pre-college experiences, the Molecular Agriculture Summer Institute (MASI) and the Purdue Agribusiness Science Academy (PASA), and participating high school …


Mapping And Analyzing Energy Use And Efficiency In A Modified Hydroponic Shipping Container, Rachel E. Sparks Aug 2016

Mapping And Analyzing Energy Use And Efficiency In A Modified Hydroponic Shipping Container, Rachel E. Sparks

Open Access Theses

In urban centers today, vertical farming is becoming a popular alternative to conventional agriculture in an effort to increase local food production and improve urban food security by growing crops using hydroponic methods in controlled environment spaces. More specifically, one vertical method involves growing crops inside refurbished shipping containers, or a “farm-in-a-box” concept, which offers a flexible, mobile, and scalable means of year-round food production in a variety of climates. Despite benefits of producing food locally, some of the concerns associated with these vertical farming systems include high energy consumption from climate control and electric lighting systems as well as …


Nutrient Runoff And Leachate After Land-Application Of Digestate In A Laboratory Study Using Rainfall Simulations, Min Xiao Aug 2016

Nutrient Runoff And Leachate After Land-Application Of Digestate In A Laboratory Study Using Rainfall Simulations, Min Xiao

Open Access Theses

There has been an increasing number of anaerobic digesters on livestock farms in the United States during the past two decades. Anaerobic digestion of manure allows production of renewable energy and generation of stabilized and nutrient-rich digestate that can be used as organic fertilizer. However, the majority of the existed studies using liquid digestate as fertilizer only focused on the effectiveness for crop yield, nutrient content and microorganism in soil. There is insufficient understanding in the environmental impact of digestate land-application. This laboratory study used six treatments including four different liquid digestate treatments, a chemical fertilizer treatment, and an unfertilized …


Irrigation Adoption, Groundwater Demand And Policy In The U.S. Corn Belt, 2040-2070, Molly A. Van Dop Aug 2016

Irrigation Adoption, Groundwater Demand And Policy In The U.S. Corn Belt, 2040-2070, Molly A. Van Dop

Open Access Theses

Climate change across the U.S. Corn Belt will significantly increase precipitation variability and temperatures by midcentury. Corn and soybean producers will seek to find strategies that may help to mitigate the potentially negative effects on yield. The adoption of irrigation technology has increased over the last several decades to improve yields in areas with insufficient rainfall, and is currently being adopted by producers who are choosing to minimize risk due to weather variability. To see if this trend in irrigation adoption has the potential to expand in the wake of climate change, this study uses weather data from four General …


Enhancing Silymarin Fractionation Via Molecular Modeling Using The Conductor-Like Screening Model For Real Solvents, Emma C. Brace Aug 2016

Enhancing Silymarin Fractionation Via Molecular Modeling Using The Conductor-Like Screening Model For Real Solvents, Emma C. Brace

Open Access Theses

The market for bio-based products from plant sources is on the rise. There is a global challenge to implement environmentally clean practices for the production of fuels and pharmaceuticals from sustainable resources. A significant hurdle for discovery of comparable plant-derived products is the extensive volume of trial-and-error experimentation required. To alleviate the experimental burden, a quantum mechanics based molecular modeling approach known as the COnductor-like Screening Model for Real Solvents (COSMO-RS) was used to predict the best biphasic solvent system to purify silymarins from an aqueous mixture. Silymarins are a class of flavonolignans present in milk thistle ( Silybum marianum …


Manipulating Air And Root-Zone Temperature For Energy-Efficient Floriculture Crop Production, Madeline W. Olberg Aug 2016

Manipulating Air And Root-Zone Temperature For Energy-Efficient Floriculture Crop Production, Madeline W. Olberg

Open Access Theses

Given the high energy costs for greenhouse floriculture production, growers are constantly searching for more energy-efficient methods of production. For example, some growers will lower greenhouse air temperature set points or grow crops in unheated high tunnels (HTs) or outdoors in order to minimize or eliminate heating costs. Unfortunately, development can be delayed and morphology can be altered if the mean daily air temperature (MDT) is reduced. We proposed that reducing MDT in combination with root-zone heating (RZH) could be an energy-efficient method for producing high-quality floriculture crops without significant delays. Unheated HT and unprotected outdoor production are very low-cost …


Effects Of Lake Erie Hypoxia On Fish Habitat Quality And Yellow Perch Behavior And Physiology, Leah Zoe Almeida Apr 2016

Effects Of Lake Erie Hypoxia On Fish Habitat Quality And Yellow Perch Behavior And Physiology, Leah Zoe Almeida

Open Access Theses

Hypoxia is a concern in freshwater, marine, and estuarine systems worldwide including in Lake Erie, North America. Hypoxia may develop more frequently and for a longer duration as a result of excess nutrient loading from human sources, therefore, the incidence of hypoxic areas has increased with human population increases and intensive land-use practices. The effects of hypoxia on fish and other aquatic organisms have been well-studied, but most research examines the negative aspects of hypoxia development on habitats and the effect of severe hypoxia on individuals. In this study we focused on less studied and more subtle effects of hypoxia, …


Economic And Environmental Impacts Of A Hypothetical Global Gmo Ban, Harrison H. Mahaffey Apr 2016

Economic And Environmental Impacts Of A Hypothetical Global Gmo Ban, Harrison H. Mahaffey

Open Access Theses

The objective of this research is to assess the global economic and greenhouse gas emission impacts of GMO crops. This is done by modeling two counterfactual scenarios and evaluating them apart and in combination. The first scenario models the impact of a global GMO ban. The second scenario models the impact of increased GMO penetration. The focus is on the price and welfare impacts, and land use change greenhouse gas (GHG) emissions associated with GMO technologies. Much of the prior work on the economic impacts of GMO technology has relied on a combination of partial equilibrium analysis and econometric techniques. …


Investigating U.S. Resident Perceptions Of Corporate Social Responsibility In Food And Agriculture, Carissa Jae Morgan Apr 2016

Investigating U.S. Resident Perceptions Of Corporate Social Responsibility In Food And Agriculture, Carissa Jae Morgan

Open Access Theses

Corporations are prioritizing corporate social responsibility (CSR) activities by investing in and actively promoting their social practices. In the U.S. of the modern food supply chain creates a unique challenge for corporations to address concerns about social issues of consumers and non-consumers alike. This study is motivated by the need to better understand individuals’ perceptions of CSR as it pertains to the food supply chain. In April 2015 an online survey collected information from 1,201 U.S. residents with the objective of investigating individuals’ perceptions of relative importance of eight prominent CSR areas relevant to food and agriculture. Demographic, household consumption, …


Tolerance As A Novel Mechanism Of Hessian Fly Control On Wheat, Kirsten E. Roe Apr 2016

Tolerance As A Novel Mechanism Of Hessian Fly Control On Wheat, Kirsten E. Roe

Open Access Theses

The effects of Hessian fly (Mayetiola destructor Say) infestation on the putative tolerant wheat line Pioneer ®brand variety 25R78 were investigated at the seedling stage. Measurements, including leaf and tiller number, leaf growth rate, and total leaf lengths were recorded for two time intervals, 16 and 32 days post infestation (dpi). At 16 dpi, total leaf length changes and leaf growth rates were significantly lower for infested tolerant plants versus uninfested plants. No permanent growth effects occurred in the 32-day set. There were no significant differences in change in leaf length and leaf growth rate in infested tolerant plants …


Consonant Discrimination In The Inferior Colliculus Of Young And Aged Rats, Christopher S. Soverns Apr 2016

Consonant Discrimination In The Inferior Colliculus Of Young And Aged Rats, Christopher S. Soverns

Open Access Theses

Complex acoustic stimuli are thoroughly encoded and processed along the primary auditory pathway to give reliable and relevant information about the environment, and elucidating the neural coding mechanisms is essential to informing clinical attempts to combat auditory dysfuntion. Receiving a uniquely diverse set of ascending and descending inputs, the inferior colliculus (IC) is a site of intricate temporal processing. In this work, natural and modified human speech is used to investigate discrimination of voice onset time (VOT) in the spiking output of IC neurons. A template-matching classification model is proposed in which single stimulus presentation responses are correlated with aggregate …


Nestmate Recognition In Odorous House Ants (Tapinoma Sessile): Effects Of Social Plasticity, Urbanization, And Laboratory Maintenance, Timothy J. Luttermoser Apr 2016

Nestmate Recognition In Odorous House Ants (Tapinoma Sessile): Effects Of Social Plasticity, Urbanization, And Laboratory Maintenance, Timothy J. Luttermoser

Open Access Theses

Odorous house ants (Tapinoma sessile) are a widespread North American ant species and common nuisance pest. In addition to their pest status, odorous house ants are of interest as a model system for understanding the factors that lead to variable queen number and nesting strategy across ants, as well as possible insight into common traits of exotic invasive (or “tramp”) ant species. While T. sessile is native to North America, in urban environments it forms large supercolonies with many queens and nest sites connected by trails, similar to a variety of exotic invasive ants, most of which are …


Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman Mar 2016

Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman

Open Access Theses

Lung cancer is the leading cause of cancer deaths in the United States, accounting for 27% of all cancer induced deaths1. In an attempt to create a effective targeted therapy for the treatment of lung cancer, a strategy used to treat an activated KrasG12D/+;p53 R172H/+ transgenic lung cancer mouse model was to deliver a known tumor suppressive microRNA (miRNA) to stop tumor growth. The tumor suppressive miRNA let-7 was lentivirally delivered in the form of its primary transcript, pri-let-7a-1, and resulted in increased lung size and inflammation compared to lungs exposed to a control lentivirus. It was identified …


Effect Of Volunteer Corn Density On Deoxynivalenol Production By Fusarium Graminearum In Hybrid Corn, Gaelle Florence Hollandbeck Feb 2016

Effect Of Volunteer Corn Density On Deoxynivalenol Production By Fusarium Graminearum In Hybrid Corn, Gaelle Florence Hollandbeck

Open Access Theses

Fusarium graminearum causes Gibberella ear rot in corn and produces mycotoxins such as deoxynivalenol (DON). Volunteer corn is a weed resulting from uncollected kernels from the previous harvest and is very difficult to control once established. An experiment was established in Porter County, IN from 2013 to 2015 to examine the impact of volunteer corn density on Gibberella ear rot severity and DON levels in hybrid corn. Five densities of volunteer corn were established within plots of each hybrid (0, 0.5, 2, 4, and 8 volunteer plants/m2). Disease severity and DON were assessed for both hybrid and volunteer ears collected …


The Effect Of Adjuvants On Apple Disease Management, Chelsi Patricia Abbott Jan 2016

The Effect Of Adjuvants On Apple Disease Management, Chelsi Patricia Abbott

Open Access Theses

The management of common apple diseases such as apple scab ( Venturia inaequalis) and bitter rot (Colletotrichum spp.) relies heavily on effective fungicide applications. However, the development of fungicide resistance to newer fungicides has resulted in management failures and significant economic losses. This has led to a greater reliance on captan, an older fungicide, because there is a low risk of pathogens developing resistance. Label restrictions limit growers to 18 kg of captan per season, which may not provide sufficient control of both apple scab and bitter rot in wet years. Consequently, apple growers are faced with two …


Susceptibility Of Parkinson’S Disease Following Mild Blast Traumatic Brain Injury, Glen Howel Galicia Acosta Jul 2015

Susceptibility Of Parkinson’S Disease Following Mild Blast Traumatic Brain Injury, Glen Howel Galicia Acosta

Open Access Theses

Blast injury-induced neurotrauma (BINT) is steadily increasing in prevalence due to escalated terror activity and constitutes the signature injury associated with current military conflicts. BINT produces significant neurological deficiencies and there is a growing concern that the injury may produce long-term consequences that affect the resilience and the performance of soldiers. One of the potential consequences is an increased susceptibility to Parkinson's disease (PD). A vital goal aimed at curtailing the post-deployment long-term consequences of blast injury-induced neurotrauma is to further our knowledge of pathogenic mechanisms responsible for the escalation of post injury diseases. The purpose of this project is …


Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford Apr 2015

Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford

Open Access Theses

A growing concern of soil health and long-term sustainability has increased interest in no-till and cover crops in the Midwest. Some of the challenges with no-till in the Midwest can be higher soil moisture and lower soil temperatures at cash crop planting in the spring, planter adjustment issues, and lack of immediate economic benefit. Cover crops also have some of the same issues along with extra cost of seed and termination, mismanagement of cover crops, and lack of knowledge on the benefits and costs. This project was begun in order to quantify the effects of no-till and cover crops on …


Are Cover Crops Worth It? It Depends, Joshua S. Leirer Apr 2015

Are Cover Crops Worth It? It Depends, Joshua S. Leirer

Open Access Theses

Society is becoming increasingly more aware of the environmental consequences of agricultural production. Farmers today are under increasing pressure to adopt more sustainable farm management practices. One method to improve the sustainability of crop production is the use of cover crops. Cover crops are planted "off-season" to provide agronomic and environmental benefits. The objective of this research is to quantify the impacts of cover crops and determine where and under which management practices cover crops provide the greatest benefit. Management practices include different crop rotations, tillage practices and residue removal rates. This paper will focus on soil erosion, nitrate leaching …


Use Of Plastic Bottles As An Alternative Container Type For Propagation Of Forest Tree Seedlings In Restoration Programs, Safiullah Khurram Apr 2015

Use Of Plastic Bottles As An Alternative Container Type For Propagation Of Forest Tree Seedlings In Restoration Programs, Safiullah Khurram

Open Access Theses

Deforestation and forest degradation is a global issue, especially in poor and developing regions of the world. In order to combat deforestation it is critical to enhance the productivity of forest restoration operations, which often involve planting of nursery-grown forest tree seedlings. Production of low quality stock types with deformed and spiraled root systems is a significant issue hindering successful restoration programs. Polybags (i.e., small plastic bags) are a common container type for seedling propagation in developing countries. However, polybags produce seedlings with spiraled and deformed root systems that reduce outplanting survival and performance. Use of discarded plastic water bottles …


Cerebrovascular Reactivity Alterations Due To Subconcussive Repetitive Head Trauma In Asymptomatic High School Football Players, Chetas Joshi Apr 2015

Cerebrovascular Reactivity Alterations Due To Subconcussive Repetitive Head Trauma In Asymptomatic High School Football Players, Chetas Joshi

Open Access Theses

Chronic neurological damage as a result of chronic repetitive head trauma is a major concern for football athletes today. Repetitive concussions have been linked to many neurological disorders. Recently, it has been reported that repetitive subconcussive events can contribute to long-term neurodegeneration. For these reasons, it is important to understand the effect repetitive subconcussive head trauma has on brain health in young athletes. Past research has demonstrated that cerebrovascular reactivity (CVR), an important mediator of cerebrovascular regulation, is impaired following mild traumatic brain injury (mTBI). This impairment increases susceptibility to secondary injury following mTBI. In this study, Breath-Hold (BH) task …


Does A Family-First Philosophy Affect Family Business Profitability? An Analysis Of Family Businesses In The Midwest, Maria Victoria Iglesias Apr 2015

Does A Family-First Philosophy Affect Family Business Profitability? An Analysis Of Family Businesses In The Midwest, Maria Victoria Iglesias

Open Access Theses

Previous family business literature has analyzed how various management strategies or family tension has impacted profit. However, profit can vary due to the different family values and goals placed on the firm. The purpose of this study was to investigate how the business philosophy of a family business influenced profit. The present study sought to examine how the family business' philosophy, as in if they have a family-first or business-first orientation, influences profit. This study also investigates how the distribution of the business to the next generation, as well as how hiring family members who may not have the qualifications …


The Bone-Protective Effect And Mechanism Of Soluble Corn Fiber, Steven A. Jakeman Apr 2015

The Bone-Protective Effect And Mechanism Of Soluble Corn Fiber, Steven A. Jakeman

Open Access Theses

Postmenopausal women are at greatest risk among healthy individuals of developing osteoporosis and associated fractures. Nondigestible, fermentable dietary carbohydrates have been shown to improve calcium absorption in adolescents and bone-strength parameters in the rat model. Of particular interest is soluble corn fiber (SCF), which improved rat bone strength the most in a survey of novel fibers, and improved calcium absorption by up to 13% in teen girls. Hypotheses about the mechanism behind this effect revolve around the production of short-chain fatty acids (SCFAs) in the large intestine during fermentation. The purpose of this work was to determine if SCF would …


Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora Apr 2015

Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora

Open Access Theses

Diabetes is a growing concern in the United States and around the world that must be addressed through new treatment options. Current standard treatment options of diabetes are limiting and have tremendous impacts on patient's lives. Emerging therapies, such as the implantation of encapsulated islets, are promising treatment options, but have not yet materialized due to unsolved problems with material properties. Hybrid silica-collagen membranes address some of these unsolved problems and are a promising material for cell encapsulation. However, the mass transfer properties of large molecules, such as insulin, TNF-α, IL1β, and other important proteins in the etiology of diabetes, …


Subsidizing Carbon Sequestration Via Forestry In Maryland: A Cost-Benefit Assessment, Rachel C. Hettich Apr 2015

Subsidizing Carbon Sequestration Via Forestry In Maryland: A Cost-Benefit Assessment, Rachel C. Hettich

Open Access Theses

Carbon sequestration by forestry is one way to mitigate climate change, and policy incentives are in place to encourage private investment in forestry. State and federal forestry cost-share programs subsidize the establishment of trees and the improvement of existing forested land. The objective of this research was to determine the effectiveness of such programs in Maryland and to compare the monetized benefits from permanently sequestered carbon with the current subsidies. To meet this objective, private and social cost-benefit analyses were conducted for three forestry investment scenarios in Maryland that coincide with the main cost-share programs available there. Sensitivity analysis considered …