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2013

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Arachidonic Acid Reverses The Pyriproxyfen And Ibuprofen Induced Toxicity In Daphnia Magna, Gautam Kumar Ginjupalli Dec 2013

Arachidonic Acid Reverses The Pyriproxyfen And Ibuprofen Induced Toxicity In Daphnia Magna, Gautam Kumar Ginjupalli

All Dissertations

Healthy reproduction and neonatal sex ratios of Daphnia are crucial to the health of the aquatic ecosystems in which Daphnia play principal roles in trophic transfer of nutrients. Combinations of environmental factors such as availability and quality of diet, overcrowding, hypoxia, reduced photoperiods and fall in ambient temperatures perturb normal parthenogeneic reproduction and induce sexual reproduction through male production. Male production provides a mechanism for overcoming specific stressors such as overcrowding and overwinter pond desiccation. However, it also induces a decrease in the Daphnia population that could have adverse implications on the pond ecosystem that depend on Daphnia . Interestingly, …


Ecology And Impacts Of Coyotes (Canis Latrans) In The Southeastern United States, Cady Etheredge Dec 2013

Ecology And Impacts Of Coyotes (Canis Latrans) In The Southeastern United States, Cady Etheredge

All Dissertations

Recent coyote (Canis latrans ) colonization of the southeastern United States has prompted speculation on the top-down effects of a new top predator on systems which have gone without a strong predator presence since the extirpation of the red wolf (Canis rufus ). This dissertation reports on the results of a series of investigations of the potential impact of coyotes on raccoons (Procyon lotor ) and other management issues related to coyotes in the Southeast. Chapters 1-3 present indirect field tests of the Mesopredator Release Hypothesis. Chapter 4 presents an overview of the current knowledge of the …


Biological Scaffolds For Peripheral Vascular Surgery, George Fercana Dec 2013

Biological Scaffolds For Peripheral Vascular Surgery, George Fercana

All Dissertations

The gold standards for small diameter peripheral vascular graft replacement are autologous arteries or veins; however, one-third of patients lack such vessels due to previous vessel harvesting or advanced vascular disease. A promising approach for patients in this category is tissue engineering with off-the-shelf biological vascular grafts. Three small diameter acellular scaffolds were developed and evaluated as vascular grafts. Porcine renal arteries (2-3 mm diameter, 20 mm length) were decellularized by immersion and stabilized with penta-galloyl glucose (PGG) with and without subsequent heparinization via carbodiimide chemistry. Bovine mammary (4-6 mm ID, 250 mm length) and femoral arteries (6-8 mm ID, …


Engineering Beta-Cell Spheroids For Type 1 Diabetes Treatment, Xiaoyan Liu Dec 2013

Engineering Beta-Cell Spheroids For Type 1 Diabetes Treatment, Xiaoyan Liu

All Dissertations

Diabetes mellitus, the third most common disease in the world, is a chronic metabolic disorder caused by a failure of insulin production and/or an inability to respond to insulin. Specifically, type 1 diabetes is a disorder characterized by targeted autoimmune-directed destruction of a patient's beta-cell population within the pancreatic islets of Langerhans. The current primary treatment for type 1 diabetes is daily multiple insulin injections. However, this treatment cannot provide sustained physiological release, and the insulin amount is not finely tuned to glycemia. Pancreatic transplants or islet transplants would be the preferred treatment method but the lack of donor tissue …


Identification Of Novel Genes Regulating Elastic Fiber Formation Through Expression Profiling Analysis Of Elastogenic Models, Erin Sproul Dec 2013

Identification Of Novel Genes Regulating Elastic Fiber Formation Through Expression Profiling Analysis Of Elastogenic Models, Erin Sproul

All Dissertations

Background: Particularly important to the mechanical performance of native arterial blood vessels is elastin, an extracellular matrix (ECM) protein deposited by VSMCs in the form of elastic fibers, arranged in concentric lamellae in the media of the vessel wall. In addition to serving as major structural elements of arterial walls, providing extensibility and elastic recoil, elastic fibers also influence vascular cell behaviors. For these reasons tissue engineers are attempting to exploit elastic fiber biology to enhance vascular graft design and patency. Therefore, developing a greater understanding of the molecular mechanisms of elastogenesis may offer opportunities to control elastogenesis in tissue …


Distribution, Ecology, And Trophic Relationships Of A Colonial Waterbird: The Double-Crested Cormorant, Kate Sheehan Dec 2013

Distribution, Ecology, And Trophic Relationships Of A Colonial Waterbird: The Double-Crested Cormorant, Kate Sheehan

All Dissertations

The realized distribution of an organism is dependent on the environmental characteristics of the landscape, biological interactions within the communities in which it lives, and geographic barriers to dispersal. Changes in habitat can influence landscape characteristics, and consequently, the distribution of organisms within the landscape. The Double-crested Cormorant ( Phalacrocorax auritus ) is a piscivorous waterbird implicated in human-wildlife conflicts at aquaculture facilities and natural aquatic systems where they compete for resources (fish) with anglers and commercial fishing guides. Impacts of P. auritus on aquatic systems result from their consumption of fish stocks and their contamination of water and soil …


Exploring Multiple Levels Of Performance Modeling For Heterogeneous Systems, Venkittaraman Vivek Pallipuram Krishnamani Dec 2013

Exploring Multiple Levels Of Performance Modeling For Heterogeneous Systems, Venkittaraman Vivek Pallipuram Krishnamani

All Dissertations

The current trend in High-Performance Computing (HPC) is to extract concurrency from clusters that include heterogeneous resources such as General Purpose Graphical Processing Units (GPGPUs) and Field Programmable Gate Array (FPGAs). Although these heterogeneous systems can provide substantial performance for massively parallel applications, much of the available computing resources are often under-utilized due to inefficient application mapping, load balancing, and tuning. While several performance prediction models exist to efficiently tune applications, they often require significant computing architecture knowledge for reliable prediction. In addition, they do not address multiple levels of design space abstraction and it is often difficult to choose …


The Effects Of Yoga Participation On Symptoms Associated With Menopause: A Mixed Methods Study, Brandi Crowe Dec 2013

The Effects Of Yoga Participation On Symptoms Associated With Menopause: A Mixed Methods Study, Brandi Crowe

All Dissertations

During midlife, it is expected that women will progress towards the biological state of menopause; the permanent condition of infertility due to alterations or diminution of reproductive hormones. Typically lasting 5-10 years, the menopausal transition is associated with symptoms including hot flashes, night sweats, interrupted sleep, anxiety, forgetfulness, and inconsistent mood. As these symptoms often hinder a women's successful functioning in everyday life, hormone therapy is commonly prescribed as a means for diminishing symptoms. However, many women are seeking alternative/complementary treatments that can assist in managing menopausal symptoms due to the detrimental health-risks associated with the use of conventional therapies. …


Design And Synthesis Of Polymer - Magnetic Nanoparticle Composites For Use In Biomedical Applications, Roland Stone Dec 2013

Design And Synthesis Of Polymer - Magnetic Nanoparticle Composites For Use In Biomedical Applications, Roland Stone

All Dissertations

The future of diagnostics and therapeutic drugs in biomedicine is nanoparticles. These nanoparticles come in many different shapes, sizes, and combination of materials. Magnetic nanoparticles have been studied for many years for use in biomedicine, not only for their high surface area, but also because of its unique magnetic properties. They can magnetically interact with their environment, be guided to a specific location, and manipulated to release energy in the form of heat. To ensure that these magnetic nanoparticles survive in the circulatory system, they must be modified with materials to make them colloidally stable in water and shield them …


Approximation In Multiobjective Optimization With Applications, Lakmali Weerasena Dec 2013

Approximation In Multiobjective Optimization With Applications, Lakmali Weerasena

All Dissertations

Over the last couple of decades, the field of multiobjective optimization has received much attention in solving real-life optimization problems in science, engineering, economics and other fields where optimal decisions need to be made in the presence of trade-offs between two or more conflicting objective functions. The conflicting nature of objective functions implies a solution set for a multiobjective optimization problem. Obtaining this set is difficult for many reasons, and a variety of approaches for approximating it either partially or entirely have been proposed.

In response to the growing interest in approximation, this research investigates developing a theory and methodology …


L1 Methods For Shrinkage And Correlation, Jie Shen Dec 2013

L1 Methods For Shrinkage And Correlation, Jie Shen

All Dissertations

This dissertation explored the idea of L1 norm in solving two statistical problems including multiple linear regression and diagnostic checking in time series. In recent years L1 shrinkage methods have become popular in linear regression as they can achieve simultaneous variable selection and parameter estimation. Their objective functions containing a least squares term and an L1 penalty term which can produce sparse solutions (Fan and Li, 2001). Least absolute shrinkage and selection operator (Lasso) was the first L1 penalized method proposed and has been widely used in practice. But the Lasso estimator has noticeable bias and is inconsistent for variable …


Abstract Models Of Molecular Walkers, Oleg Semenov Dec 2013

Abstract Models Of Molecular Walkers, Oleg Semenov

Computer Science ETDs

Recent advances in single-molecule chemistry have led to designs for artificial multi-pedal walkers that follow tracks of chemicals. The walkers, called molecular spiders, consist of a rigid chemically inert body and several flexible enzymatic legs. The legs can reversibly bind to chemical substrates on a surface, and through their enzymatic action convert them to products. We study abstract models of molecular spiders to evaluate how efficiently they can perform two tasks: molecular transport of cargo over tracks and search for targets on finite surfaces. For the single-spider model our simulations show a transient behavior wherein certain spiders move superdiffusively over …


Model Selection For Stochastic Block Models, Xiaoran Yan Dec 2013

Model Selection For Stochastic Block Models, Xiaoran Yan

Computer Science ETDs

As a flexible representation for complex systems, networks (graphs) model entities and their interactions as nodes and edges. In many real-world networks, nodes divide naturally into functional communities, where nodes in the same group connect to the rest of the network in similar ways. Discovering such communities is an important part of modeling networks, as community structure offers clues to the processes which generated the graph. The stochastic block model is a popular network model based on community structures. It splits nodes into blocks, within which all nodes are stochastically equivalent in terms of how they connect to the rest …


The Role Of Heparin In Acidic Fibroblast Growth Factor Signaling, Rebecca Kerr Dec 2013

The Role Of Heparin In Acidic Fibroblast Growth Factor Signaling, Rebecca Kerr

Graduate Theses and Dissertations

Fibroblast growth factors (FGFs) are a superfamily of 23 heparin-binding proteins. Acidic fibroblast growth factor (FGF1) is a 16 kDa protein that is involved in many important biological processes such as cell differentiation, angiogenesis, and wound healing. FGF1 exhibits its activity by binding to cell-surface tyrosine kinase receptors (FGFRs). In addition to binding to FGFRs, FGF1 binds to heparin/HLGAGs. Heparin is proposed to have two functions: it protects FGFs from degradation by proteases and from thermal denaturation; and upon binding it induces FGF1 oligomerization, which is mandatory for binding to FGFR. However, it remains controversial whether or not heparin is …


Investigation Of The Life History And Lipid Content Consequences Of Reduced Abundance Of Delta-9 Desaturases In Drosophila Melanogaster, Li Ko Dec 2013

Investigation Of The Life History And Lipid Content Consequences Of Reduced Abundance Of Delta-9 Desaturases In Drosophila Melanogaster, Li Ko

School of Biological Sciences: Dissertations, Theses, and Student Research

Monounsaturated fatty acids (MUFAs) are essential components in all organisms, and the key enzymes that catalyze the production of MUFA are delta-9 desaturases. These enzymes are ER bound and introduce the first double bonds in saturated fatty acids. To investigate the role that delta-9 desaturases play in Drosophila life history and development we performed a series of studies using the RNAi method. Longevity results showed die-off peaks of the knocked-down (KD) flies at day 45. Fecundity study showed decreases in both egg productions and viability of these eggs. Development difficulties were observed in both regular diet and low fat diet. …


Trade-Offs In Male Lek Behavior, Sarah A. Cowles Dec 2013

Trade-Offs In Male Lek Behavior, Sarah A. Cowles

School of Biological Sciences: Dissertations, Theses, and Student Research

In lek mating systems, males aggregate together and perform courtship displays to visiting females. However, display may be energetically expensive and reduce the time available for foraging. These costs in turn could lower energy reserves, which could decrease survival. I examined trade-offs in male lek behavior using two methods: 1) I conducted an empirical study of how sharp-tailed grouse (Tympanuchus phasianellus) males allocate time between courtship display (“dancing”), agonism, foraging, and inactivity in relation to female numbers both within and across days. I also measured head turning rates during these same behaviors as a proxy for visual attentiveness …


The Roles Of Phenotypic Plasticity And Genotypic Specialization In High Altitude Adaptation, Danielle M. Tufts Dec 2013

The Roles Of Phenotypic Plasticity And Genotypic Specialization In High Altitude Adaptation, Danielle M. Tufts

School of Biological Sciences: Dissertations, Theses, and Student Research

In vertebrates living at high altitude, arterial hypoxemia may be ameliorated by reversible changes in the oxygen-carrying capacity of the blood (regulated by erythropoiesis) and/or changes in blood–oxygen affinity (regulated by allosteric effectors of hemoglobin function). These hematological traits often differ between taxa that are native to different elevational zones, but it is often unknown whether the observed physiological differences reflect fixed, genetically based differences or environmentally induced acclimatization responses (phenotypic plasticity). Here, we report measurements of hematological traits related to blood–O2 transport in populations of deer mice (Peromyscus maniculatus) that are native to high- and low-altitude …


An Efficient Two Sample Capture-Recapture Model With High Recaptures, Danjuma Jibasen, Yusuf J. Adams Dec 2013

An Efficient Two Sample Capture-Recapture Model With High Recaptures, Danjuma Jibasen, Yusuf J. Adams

CBN Journal of Applied Statistics (JAS)

This paper proposed an efficient two sample capture-recapture model (Ma) with high recaptures and compared it with the existing models like the model of no factor effect (Mo), behavioral response model (Mb) and the Petersen model (Ms), using simulated data. We found that the Petersen model provides a better estimate of the population size when the observations follow a hypergeometric distribution and the population is overestimated when recapture is high. It was also found that the proposed model provides a better estimator of the population size than the existing ones when the recapture is high. This model is particularly useful …


Evaluating Flexibility In International Patent Law, Sarah R. Wasserman Rajec Dec 2013

Evaluating Flexibility In International Patent Law, Sarah R. Wasserman Rajec

Faculty Publications

Global patent law has raced toward harmonization over the past decades. Countries with vastly different industries, values, and levels of development now offer robust patent rights with similar contours through membership in the World Trade Organization and consequent adoption of the Agreement on Trade-Related Aspects of Intellectual Property Rights (“TRIPS”). However, patent law is still far from harmonized among countries or static within countries. Jurisdictions tailor their patent laws to accommodate differences between industries, unforeseen inefficiencies, and diverse views of the costs and benefits associated with offering patent rights to stimulate innovation. Prior scholarly work consists of either doctrinal analyses …


Stressors Perceived By Physicians In Taiwan: A Focus Group Interview, Yen-Yuan Chen, Ming-Been Lee, Shih-Cheng Liao, Chia-Ming Chang Dec 2013

Stressors Perceived By Physicians In Taiwan: A Focus Group Interview, Yen-Yuan Chen, Ming-Been Lee, Shih-Cheng Liao, Chia-Ming Chang

Journal of Medical Education

Purpose: The workload and working time of health care workers have become a critical issue in Taiwan, and attracted a lot of attention not only from health care workers, but also the general public as well as health care authority. Few studies investigated the stressors that physicians encounter in their daily clinical practice in Taiwan. This study aimed to investigate the stressors that physicians perceive. Methods: We conducted a qualitative study using focus group interviews to examine the stressors. Criteria sampling was used based on the following criteria: (1) having an experience of clinical practice for more than four years; …


Development Of A Control Banding Method For Selecting Respiratory Protection Against Bioaerosols, Jacques Lavoie, Eve Neesham-Grenon, Maximilien Debia, Yves Cloutier, Geneviève Marchand Dec 2013

Development Of A Control Banding Method For Selecting Respiratory Protection Against Bioaerosols, Jacques Lavoie, Eve Neesham-Grenon, Maximilien Debia, Yves Cloutier, Geneviève Marchand

Rapports de recherche scientifique

La sélection d’un appareil de protection respiratoire contre les bioaérosols peut s’avérer une tâche complexe compte tenu de l’absence de valeurs limites d’exposition et de données toxicologiques, ainsi que des limites des techniques d’échantillonnage actuelles et de la grande diversité des bioaérosols. Dans ces circonstances, une méthode qualitative d’évaluation et de gestion du risque fournit une alternative aux méthodes quantitatives utilisées en hygiène du travail. Ce rapport propose un modèle de gestion graduée du risque pour le choix de la protection respiratoire contre les bioaérosols infectieux et non infectieux applicable à l’ensemble des milieux de travail et s’adressant aux hygiénistes …


A Northward Range Extension Of The Hispid Cotton Rat (Sigmodon Hispidus) In Missouri, Cody W. Thompson, Elmer J. Finck Dec 2013

A Northward Range Extension Of The Hispid Cotton Rat (Sigmodon Hispidus) In Missouri, Cody W. Thompson, Elmer J. Finck

The Prairie Naturalist

The hispid cotton rat (Sigmodon hispidus) is a widely distributed rodent with a geographic range extending from north-central Mexico to southern Nebraska and central Virginia and from southeastern Arizona east to Florida (Carleton et al. 1999, Peppers and Bradley 2000, Wilson and Reeder 2005) with isolated populations in Arizona (Bradley et al. 2012) and California (Clark 1972). Range expansions for the species have been well documented (Clark 1972, Farney 1975, Benedict et al. 2000, Wright et al. 2010, Wills et al. 2011). The majority of these range expansions have occurred across the Central Plains during the 20th century …


Evaluation Of Three Nest Searching Methods For Ring-Necked Pheasant, Jeffery W. Stackhouse, Kevin K. Sedivec, Benjamin A. Geaumont Dec 2013

Evaluation Of Three Nest Searching Methods For Ring-Necked Pheasant, Jeffery W. Stackhouse, Kevin K. Sedivec, Benjamin A. Geaumont

The Prairie Naturalist

Ring-necked pheasant (Phasianus colchicus) are a highly sought after game bird and as such, much research has been conducted regarding their ecology (Warner 1981, Trautman 1982, Johnson and Knue 1989). Perhaps the most investigated aspect of pheasant ecology is the species’ reproductive season (e.g. Linder et al. 1960, Dumke and Pils 1979, Leif 1994) with many studies focusing on nesting habitat (Baskett 1947, Clark et al. 1999). Results from previous research have acknowledged the difficulty associated with locating pheasant nests in their preferred cover types (Hanson 1970, Evrard 2000). Studies of pheasant nesting ecology have been based on …


How Important Is A Quality Manuscript Review?, Christopher N. Jacques Dec 2013

How Important Is A Quality Manuscript Review?, Christopher N. Jacques

The Prairie Naturalist

Temperatures are finally starting to cool a bit (for those of us in the northern Great Plains region) and Thanksgiving break is just around the corner.

I offer my reflections in the spirit of encouraging each of you to take a break from your professional obligations and spend time with friends and family enjoying nature and everything it has to offer this fall.


Salamander Colonization Of Chase Lake, Stutsman County, North Dakota, David M. Mushet, Kyle I. Mclean, Craig A. Stockwell Dec 2013

Salamander Colonization Of Chase Lake, Stutsman County, North Dakota, David M. Mushet, Kyle I. Mclean, Craig A. Stockwell

The Prairie Naturalist

Salt concentrations in lakes are dynamic. In the western United States, water diversions have caused significant declines in lake levels resulting in increased salinity, placing many aquatic species at risk (Galat and Robinson 1983, Beutel et al. 2001). Severe droughts can have similar effects on salt concentrations and aquatic communities (Swanson et al. 2003). Conversely, large inputs of water can dilute salt concentrations and contribute to community shifts (Euliss et al. 2004).

Chase Lake is a large, shallow, alkaline lake in east-central North Dakota most famously known for supporting one of the largest breeding colonies of the American white pelican …


Associations Between Iron Concentration And Productivity In Montane Streams Of The Black Hills, South Dakota, Cari-Ann Hayer, Benjamin M. Holocmb, Steven R. Chipps Dec 2013

Associations Between Iron Concentration And Productivity In Montane Streams Of The Black Hills, South Dakota, Cari-Ann Hayer, Benjamin M. Holocmb, Steven R. Chipps

The Prairie Naturalist

Iron is an important micronutrient found in aquatic systems that can influence nutrient availability (e.g. phosphorus) and primary productivity. In streams, high iron concentrations often are associated with low pH as a result of acid mine drainage, which is known to affect fish and invertebrate communities. Streams in the Black Hills of South Dakota are generally circumneutral in pH, yet select streams exhibit high iron concentrations associated with natural iron deposits. In this study, we examined relationships among iron concentration, periphyton biomass, macroinvertebrate abundance, and fish assemblages in four Black Hills streams. The stream with the highest iron concentration (~5 …


Relationships Among Walleye Mercury, Selenium, Stable Isotopes, Size And Age, Mark J. Fincel, Robert P. Hanten, Shannon Minerich Dec 2013

Relationships Among Walleye Mercury, Selenium, Stable Isotopes, Size And Age, Mark J. Fincel, Robert P. Hanten, Shannon Minerich

The Prairie Naturalist

Bioaccumulation of mercury is well-documented in aquatic ecosystems and occurs as mercury is accumulated and passed up food chains (Kidd et al. 1995, Atwell et al. 1998, Downs et al. 1998). Trophic level correlations have been widely reported for mercury (Snodgrass et al. 2000) and other metals (Barron 1995). Generally, within a system, carnivores have the highest mercury loadings, omnivores intermediate and herbivores the lowest (Phillips et al. 1980). However, little research has focused on the differences in mercury bioaccumulation for a single species that ranges across multiple trophic levels (Burger et al. 2001).

Stable isotope analysis has expanded the …


Analysis Of Participation In 21st Century Community Learning Center After-School Program And Student Grade Five Achievement, Willie T. Herbert Dec 2013

Analysis Of Participation In 21st Century Community Learning Center After-School Program And Student Grade Five Achievement, Willie T. Herbert

Student Work

This study explored the fifth grade achievement in reading, math, and language as measured by the California Achievement Test for students who were selected because of at-risk factors into an after-school achievement and enrichment program. Students in grades one to five attended this 21st Century Learning Center Program from one to five days per week. Means of fifth grade achievement from participants in 2008-2012 were compared to the means of students within the same school setting.


A New Species Of Euscorpius From Tinos Island, Greece (Scorpiones: Euscorpiidae), Victor Fet, Michael E. Soleglad, Aristeidis Parmakelis, Panayiota Kotsakiozi, Iasmi Stathi Dec 2013

A New Species Of Euscorpius From Tinos Island, Greece (Scorpiones: Euscorpiidae), Victor Fet, Michael E. Soleglad, Aristeidis Parmakelis, Panayiota Kotsakiozi, Iasmi Stathi

Biological Sciences Faculty Research

The scorpion genus Euscorpius has been insufficiently studied on the Aegean Islands of Greece. We describe a new species from the Western Cyclades, E. kritscheri sp. n., from Tinos Island. The species-level status of this form is confirmed by a phylogenetic study based on multiple DNA markers. In addition, a population from nearby Andros Island is characterized as E. cf. kritscheri, which could be potentially a separate species.


Review Of Cerebral Aneurysm Formation, Growth, And Rupture., Nohra Chalouhi, Md, Brian L Hoh, David Hasan Dec 2013

Review Of Cerebral Aneurysm Formation, Growth, And Rupture., Nohra Chalouhi, Md, Brian L Hoh, David Hasan

Department of Neurosurgery Faculty Papers

No abstract provided.