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Full-Text Articles in Life Sciences

Lower Food Web Dynamics In Lakes Michigan And Huron: Spatial And Temporal Responses To Recent Oligotrophication, Margaret Hutton Stadig Dec 2016

Lower Food Web Dynamics In Lakes Michigan And Huron: Spatial And Temporal Responses To Recent Oligotrophication, Margaret Hutton Stadig

Open Access Theses

Nutrient abatement programs, originally enacted to counter eutrophication have successfully suppressed nutrient loads and relative primary production in marine and freshwater systems. Recently, the additive impacts of invasive filter feeders have further reduced offshore primary production in several aquatic systems throughout the world. It has been hypothesized that the biological activity of these invasive species may sequester nutrients within the nearshore benthic environment, creating steep gradients in primary production between nearshore and offshore habitats. In the Laurentian Great Lakes, past studies of oligotrophication have primarily focused on food web responses in offshore habitats. Organisms at higher trophic levels have been ...


Mathematical Analysis Of Feedback Targets Of Bmp Signaling In Drosophila Embryonic Development, Yan Luo Dec 2016

Mathematical Analysis Of Feedback Targets Of Bmp Signaling In Drosophila Embryonic Development, Yan Luo

Open Access Theses

Bone morphogenetic proteins (BMPs) drive a range of cellular processes especially in the early stages of embryonic development. This family of proteins acts as one of the most important extracellular signals in development pattern formation across the animal kingdom. Cells in embryos differentiate into different cell types in response to the concentration level of BMP. This complex process is regulated by multiple regulators that serve to tune the signal response.

Extensive experimental and computational research has been performed to analyze BMP regulation in Drosophila, a widely studied model organism, and has advanced our understanding of animal development. Because of BMP ...


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 ...


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 ...


Pilot Study Of The Effect Of High-Protein, Renal-Appropriate Meals During Hemodialysis On Intradialytic Hypotension In Maintenance Hemodialysis Patients, Mun Sun Choi Aug 2016

Pilot Study Of The Effect Of High-Protein, Renal-Appropriate Meals During Hemodialysis On Intradialytic Hypotension In Maintenance Hemodialysis Patients, Mun Sun Choi

Open Access Theses

Background: In the United Sates (US), more than 400,000 people have end stage renal disease (ESRD) or chronic kidney disease (CKD) stage 5D requiring in-center hemodialysis (HD), and approximately $35 billion is spent annually in healthcare costs. Maintenance HD patients with ESRD have increased protein (1.2 g/kg/d) and energy (30-35 kcal/kg/d) requirements, but the average protein and energy intake in these patients is only 0.8-1.0 g/kg/d and 20-25 kcal/kg/d, respectively. Subsequently, protein-energy wasting (PEW) is common, affecting up to an estimated 75% of maintenance HD patients, and low ...


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 ...


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 ...


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 ...


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 ...


Analysis Of Vitamin E Metabolites By Liquid Chromatography-Tandem Mass Spectrometry, Tianlin Xu Oct 2014

Analysis Of Vitamin E Metabolites By Liquid Chromatography-Tandem Mass Spectrometry, Tianlin Xu

Open Access Theses

Naturally occurring forms of Vitamin E are metabolized to various carboxychromanols and conjugated carboxychromanols. Recent studies showed that vitamin E metabolites, especially the long-chain carboxychromanols are more bioactive than unmetabolized vitamin E forms. It is necessary to quantify vitamin E metabolites in biological environment. Here a simple and effective extraction method was developed to achieve extraction efficacy of more than 90% of various forms of vitamin E and metabolites with less than 10% inter- or intra-day variation. An LC-MS/MS assay was developed and optimized to acquire best sensitivity for the detection of vitamin E and metabolites. This method allows ...


Postural Sway In Infants At Low And High Risk For Autism Spectrum Disorder, Rachel C. Harris Oct 2014

Postural Sway In Infants At Low And High Risk For Autism Spectrum Disorder, Rachel C. Harris

Open Access Theses

ABSTRACT Harris, Rachel C. M. S., Purdue University, December 2014. Postural Control in Infants at Low and High Risk for Autism Spectrum Disorder. Major Professor: Laura J. Claxton. Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder more commonly known for deficits in social and communication skills. More recently, aspects of motor development have been shown to be delayed in children with ASD, including deficits in their postural control abilities. Children with ASD have difficulty integrating information from their sensory systems to help control their balance. Infants at risk for ASD and infants who are later diagnosed with ASD have delays ...


The Impact Of An Omega-3 Enriched Diet On Hyperactivity And Biochemistry In An Animal Model For Attention-Deficit/Hyperactivity Disorder, Nadine M. Hammoud Oct 2014

The Impact Of An Omega-3 Enriched Diet On Hyperactivity And Biochemistry In An Animal Model For Attention-Deficit/Hyperactivity Disorder, Nadine M. Hammoud

Open Access Theses

Attention-deficit/hyperactivity disorder (ADHD) is the most diagnosed behavioral disorder in children. It affects around 5% of children worldwide and 11% of children in the United States, with rates increasing. Pharmaceutical treatments, such as amphetamines and methylphenidates, are not effective for everyone and are known to have unwanted side effects. While the etiology of the disorder is not yet fully understood, there are clear genetic and environmental components. Nutritional insufficiencies have recently become a popular environmental risk factor under investigation. Essential fatty acids (EFA), omega-3 polyunsaturated fatty acids (PUFA) in particular, are needed for proper brain development and function. Our ...


Design, Development And Testing Of A Balance Board With Variable Torsional Stiffness And Time Delay, Denise Renee Cruise Jul 2014

Design, Development And Testing Of A Balance Board With Variable Torsional Stiffness And Time Delay, Denise Renee Cruise

Open Access Theses

The ability to balance and maintain upright posture can decline for a variety of reasons, such as aging and neuromuscular impairment. As the ability to balance declines, the risk of falling increases. Falls are a major cause of injury, and often lead to a dramatic decline in quality of life. Currently, to alleviate balance deficiencies, people participate in balance training, which most commonly refers to standing on an unstable balance board; the most common boards used are either passive wobble boards, or more advanced commercial systems such as the Biodex System SD ® or the Neurocom SMART Balance Master® . Balance training ...


1,25-Dihydroxyvitamin D Alters Lipid Metabolism And Epithelialto- Mesenchymal Transition In Metastatic Epithelial Breast Cancer Cells, Alle Nicole Barnard Jul 2014

1,25-Dihydroxyvitamin D Alters Lipid Metabolism And Epithelialto- Mesenchymal Transition In Metastatic Epithelial Breast Cancer Cells, Alle Nicole Barnard

Open Access Theses

Evidence suggests that high vitamin D status (marked by serum 25-hydroxyvitamin D, 25(OH)2 D) is associated with a decreased risk of breast cancer. It has been established that 1,25-dihydroxyvitamin D (1,25(OH) 2 D) can alter glycolysis and the Krebs cycle of breast cancer cells (Jiang et al., 2010; Zheng et al., 2013) but little information is available on 1,25(OH) 2 D's alterations of lipid metabolism in breast cancer cells. Thus, the current research investigates if there was an effect of 1,25(OH) 2 D on proteins that regulate lipid metabolism in ...


Consumer Perceptions Of Child-Friendly Shaped Healthy Fruit And Vegetable Snacks, Selena Lauren Baker Apr 2014

Consumer Perceptions Of Child-Friendly Shaped Healthy Fruit And Vegetable Snacks, Selena Lauren Baker

Open Access Theses

Fruits and vegetables (FV) are widely recognized as healthful foods by the public, and most individuals are aware of dietary guidance recommendations to consume more FV. However, actual consumption of FV has been and continues to be low in the United States and many other countries, despite public health efforts to change this trend. The sub-optimal intake of FV among children and adolescents is of particular concern due to high nutrient requirements for proper growth and development during these life stages. Fruit and vegetable intake patterns in childhood have been shown to track into later life and may affect individuals ...


Neurotrophins And Their Effects On Breast Cancer Cell Proliferation And Migration, Kayla Elise Minser Apr 2014

Neurotrophins And Their Effects On Breast Cancer Cell Proliferation And Migration, Kayla Elise Minser

Open Access Theses

Cancer is a large health issue in all parts of the world. In the United States alone, approximately 1 in 4 deaths are cancer related. Breast cancer is a particularly prevalent form, accounting for a little over 14 percent of all cancer incidence. The largest obstacle to overcome for breast cancer morbidity is metastasis. Over 90 percent of all breast cancer related deaths are due to metastasis. Because metastasis is a complex, multi-step process, it is difficult to treat. A recent observation in the Kirshner lab has revealed a type of phenotypic plasticity, where migratory cancer cells have a neuronal-like ...


Deforestation Of Cloud Forest In The Central Highlands Of Guatemala: Soil Erosion And Sustainability Implications For Q'Eqchi' Maya Communities, Ian Christopher Pope Apr 2014

Deforestation Of Cloud Forest In The Central Highlands Of Guatemala: Soil Erosion And Sustainability Implications For Q'Eqchi' Maya Communities, Ian Christopher Pope

Open Access Theses

Understanding the nexus between deforestation, food production, land degradation, and culture contributes knowledge that is useful for development practitioners working to enhance conservation and food security. Documenting deforestation and soil erosion in the Sierra Yalijux and Sierra Sacranix in the Central Highlands of Guatemala adds new knowledge about the rates and dynamics of deforestation and land degradation in areas with unique and sensitive cloud forest ecosystems. It also suggests possible areas of emphasis for efforts targeted at combining cloud forest conservation with sustainability for indigenous Q'eqchi' communities. In addition, this work contributes to a small but growing body of ...


An Exploratory Analysis Of Fruit And Vegetable Consumption In Black Men, Jacqueline Reiter Apr 2014

An Exploratory Analysis Of Fruit And Vegetable Consumption In Black Men, Jacqueline Reiter

Open Access Theses

Objective: Multiple peer-reviewed studies have found an association between fruit and vegetable consumption and lower risk for diseases such as hypertension, stroke and cancer. In other related studies, education level, retail food environment, and fruit and vegetable consumption were also examined together to discover patterns and associations. Currently, Black males have a higher risk for poor health outcomes. Limited research has focused specifically on Black men's fruit and vegetable consumption. This study explored the association between education level, food store access (measured by proximity) and fruit and vegetable consumption in black African American men.

Design: The data for this ...


Efficacy Of Manual Dishwashing And Sanitizer Wiping In Removing Food Soils From Chel Knives, Xiaodi Sun Apr 2014

Efficacy Of Manual Dishwashing And Sanitizer Wiping In Removing Food Soils From Chel Knives, Xiaodi Sun

Open Access Theses

Improperly cleaned and sanitized chef knives may present a potential contamination risk and thus be a risk for foodborne illness. Therefore, ensuring effective cleaning and sanitization of knife surfaces may help prevent the spread of foodborne pathogens. The primary objective of this research was to compare the efficacies of two different cleaning methods (three-compartment manual dishwashing and sanitizer wiping) at removing food soils from contaminated chef knives using procedures that are typical of restaurant kitchens. Knife wiping and washing procedures were determined and standardized according to an observation of knife cleaning behavior in a kitchen. Adenosine triphosphate (ATP) bioluminescence was ...


Pharmaceuticals And Personal Care Products: Emerging Contaminants In Aquatic Ecosystems, Jenny E. Zenobio Apr 2014

Pharmaceuticals And Personal Care Products: Emerging Contaminants In Aquatic Ecosystems, Jenny E. Zenobio

Open Access Theses

In recent years, the presence of pharmaceuticals and personal care products (PPCPs) in aquatic systems has led to research on their fate and effects. PPCPs have been found in mixture in wastewater effluents, surface, ground, and drinking water at low concentrations from areas of intense urbanization. Although adverse effects to human health from the current environmental concentrations are unlikely, the impacts to ecological receptors are not clear. We performed field and laboratory studies to quantify and evaluate effects of PPCPs on fish. First, a field study was conducted at the Baca National Wildlife Refuge, Colorado (2010-2012) because a portion of ...


An Economic Analysis Of Sizing Constraints: Price Discrimination And Changes In Welfare Under The New York City Soda Ban, Brian A. Bourquard Apr 2014

An Economic Analysis Of Sizing Constraints: Price Discrimination And Changes In Welfare Under The New York City Soda Ban, Brian A. Bourquard

Open Access Theses

This thesis uses profit maximizing techniques and nonlinear, second-degree price discrimination theory to describe changes in consumption and gains and losses in welfare of consumption under a container size constraint. It observationally examines the New York City soda ban to provide insight into retailer behavior in the event of such a ban, and examines three cases to highlight potential retailer decisions to compensate for a ban: to continue using a restricted menu of pricing options; to sell only to high type soda consumers; or to serve both markets with a one-size-fits-all strategy. This thesis finds that the ban generally reduces ...


Fatty Acids And Mercury In Seventy Seven Species Of Commercially Available Finfish In The United States, Dennis P. Cladis Apr 2014

Fatty Acids And Mercury In Seventy Seven Species Of Commercially Available Finfish In The United States, Dennis P. Cladis

Open Access Theses

Finfish are consumed across the United States and constitute an important part of the American diet. However, seafood consumption can be a tenuous topic, with supporters highlighting the health benefits of eicosapentaenoic acid (EPA, C20:5n3) and docosahexaenoic acid (DHA, C22:6n3) and opponents emphasizing the neurotoxicity of methylmercury. Because all fish contain varying amounts of EPA, DHA, and methylmercury, the need for clear and unbiased information is essential to alleviate the confusion experienced by many consumers and empower them to make informed decisions regarding seafood consumption. As the market changes and more fish originate from aquaculture sources, where diets ...


Bridging The Omega-3 Gap: The Disparity Between Actual And Target Intakes Of Eicosapentaenoic Acid (Epa) And Docosahexaenoic Acid (Dha) In Children, Lyndsey Rae Herdzina-Huss Apr 2014

Bridging The Omega-3 Gap: The Disparity Between Actual And Target Intakes Of Eicosapentaenoic Acid (Epa) And Docosahexaenoic Acid (Dha) In Children, Lyndsey Rae Herdzina-Huss

Open Access Theses

To improve children's diet quality for optimal growth and development and the prevention of chronic disease, we conducted two studies. One was focused on analyzing nationally representative data; the other was designed to test the feasibility of children accepting and consuming oily fish in a childcare setting. The objective of our first study was to provide evidence for 2-18 year old children's fish and shellfish consumption patterns and their eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake. The aims of this study were to estimate proportion of children consuming fish, to identify major dietary sources of EPA and ...


Physical Activity Informational Websites: Accuracy, Language Ease, And Fear Appeal, Samantha Rose Paige Apr 2014

Physical Activity Informational Websites: Accuracy, Language Ease, And Fear Appeal, Samantha Rose Paige

Open Access Theses

Introduction. Health information is one of the most common searches on the Internet. Literature supports that, in general, health information readily available to Internet consumers is not accurate, lacks plain language for ease of understanding, and does not incorporate behavior-change theoretical frameworks. The purpose of this study was to evaluate each of these components. Method. Three keywords, "physical activity," "exercise," and "fitness," were entered into four popular search engines: Google, Bing, and Yahoo. The first 5 result pages were considered, totaling a sample of 493 websites. After exclusionary criteria, 102 websites were reviewed and analyzed with guidance from ACSM recommendations ...


Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker Jan 2013

Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker

Open Access Theses

Backwater habitats of large rivers provide habitat for aquatic biota and influence important predator-prey interactions in fishes and other aquatic organisms. However, these areas often exhibit turbid conditions and lack habitat complexity. Restoration of lentic habitats through direct habitat manipulations has shown success in prior efforts, but these methods have not been tested in backwater habitats of large rivers. I attempted to create habitat in an Ohio River embayment by establishing founder colonies of aquatic macrophytes coupled with the placement of underwater gravel beds. I also evaluated the effects of total suspended solids (TSS) on overwintering structures of American Pondweed ...


Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla Jan 2013

Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla

Open Access Theses

Hypocotyls isolated from mature embryos germinated on Murashige and Skoog (MS) medium supplemented with 22.2 µM 6-benzyladenine (BA) and 0.5 µM thidiazuron (TDZ) were transformed using Agrobacterium tumefaciens strain EHA105 harboring the pBI121-8D2 vector containing the neomycin phosphotransferase (nptII) gene and a full length, codon-optimized Bacillus thuringiensis Cry8Da protoxin gene (cry8D2). Explants were transformed in a bacterial suspension with 100 µM acetosyringone using 90 s sonication and 10 min vacuum-infiltration. Four independent lines of transformed shoots were selectively regenerated on MS medium with 22.2 µM BA, 0.5 µM TDZ, 50 mg L-1 adenine sulfate, 10 ...


Modeling Tools For Conformal Orthotic Devices, Steven David Riddle Jan 2013

Modeling Tools For Conformal Orthotic Devices, Steven David Riddle

Open Access Theses

The purpose of this thesis is to advance the design of conformal orthotic devices through the development of two modeling tools to address knowledge gaps in the field.

The field of human orthotics has been continually troubled by identifying successful methods of harnessing devices to the body. Past orthotics have utilized a rigid framework with minimal degrees of freedom (DOFs) driven by hard actuators attached to the body at select anchor points. Many devices design the structure and anchor points such that they reduce the degrees of freedom of a targeted joint, limiting the user's mobility and often causing ...