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Relation Ship Between Asparagine Metabolism And Protein Content In Soybean Seed, Sudhakar Pandurangan

Digitized Theses

Soybean (Glycine max [L.] Merr.) is an important crop grown primarily as a protein and oil source. Asparagine is the main form of organic nitrogen that is transported to developing seeds during seed filling in soybean and other legumes. Asparaginase (ASPG) is considered to be the major enzyme metabolizing transported asparagine in the seed coat and developing cotyledon for the synthesis of other amino acids. Beside ASPG, there is evidence for concurrent expression of asparagine synthetase (AS) enzyme in developing seeds. The determination of free asparagine at mid-maturation in three genetically related cultivars (Maple Arrow, AC-Hercule and AC-Proteus) varying in …

Genetic Diversity, Fitness And Mating Behaviour In Song Sparrows (Melospiza Melodia) (, Jenna M. Kewin

Digitized Theses

Understanding the evolutionary forces that maintain genetic diversity in natural populations is a major goal in behavioural and evolutionary ecology. I investigated the relationships between individual genetic diversity and pairwise genetic similarity (as measured by 17 microsatellite loci), mating strategies, parental investment, and overwinter survivorship, in song sparrows Melospiza melodia. Genetic similarity of socially mated pairs was not significantly different from random expectations, but females were more likely to produce extra-pair offspring when their social mate was genetically similar. Highly heterozygous males fed their nestlings significantly more often than did their less diverse counterparts, although this pattern was not observed …

Delta Relaxation Enhanced Magnetic Resonance, Jamu K. Alford

Digitized Theses

Generally speaking, targeted molecular Imaging has always been difficult to perform with magnetic resonance. The difficulty does not arise with the magnetic resonance imaging (MRI) technique or equipment itself, but rather with the targeted contrast agents, which the method requires. Also referred to as activatable contrast agents, or MRI probes, targeted contrast agents are pharmaceuticals that will selectively bind to a particular biological (target) molecule. They are used to highlight a certain tissue or the difference between healthy and diseased tissue. Unfortunately, nearly all MRI probes are non-specific, causing localized increases in MR image intensity in both the unbound and …

Enamel Matrix Proteins Enhance Osteoblast Spreading, Proliferation And Differentiation On Titanium Surfaces, Richard Miron

Digitized Theses

Modifications of implant surface topography and chemistry have proven a means to enhance osseointegration, a process that ensures the stability of bone-contacting devices including titanium dental implants. Enamel matrix derivative (EMD) extracted from developing porcine teeth, has been shown to promote regeneration of bone. The aim of the present study was to evaluate the effect of EMD on the attachment, proliferation and differentiation of osteoblasts on titanium surfaces in vitro. Pickled (smooth) and SLA (Sand-blasted with Large grit followed by Acid etching) titanium discs were coated with EMD or left uncoated. Primary rat calvarial osteoblasts were cultured on each surface …

The Relationship Between Social Rank, Neophobia, And Observational Learning In Black-Capped Chickadees, Yong Seok An

Digitized Theses

Behavioural syndromes are consistent individual behavioural tendencies across varying situations. Although behavioural syndromes studies are becoming more common, few draw connections to social dominance. Black-capped chickadees (Poecile atricapillus) flock in winter, and dominance hierarchies are critical to their survival. To determine the relationship between social rank, neophobia and observational learning in chickadees, we measured individual reactions to novelty and individual differences in foraging-task learning ability. Latencies to approach different novel stimuli were correlated within individuals. Social rank was related to individual reactions to novelty but not to foraging- task learning ability. Lower ranking individuals were less neophobic, consistent with their …

The Evolution Of Cold Tolerance In Drosophila Species Larvae, Lauren Anne Strachan

Digitized Theses

Insects survive subzero environments by using cold tolerance strategies divided into two categories: freeze avoidance or freeze tolerance. In spite of extensive research on insect cold tolerance, it remains unclear whether a phylogenetic constraint exists on the “choice” of cold tolerance strategy. Most freeze tolerant dipteran species survive freezing as larvae; however, previous Drosophila studies have focused primarily on the adult fly. I suggest that both freeze avoiding and freeze tolerant strategies will be present in Drosophila larvae, and I used a comparative approach to examine this and other cold tolerance attributes in a phylogenetically-independent context. Supercooling capacity was attributed …

The Role Of A Spinothalamic Pathway Regulating Sexual Inhibition And Reward, Allisha M. Bailey

Digitized Theses

Male sexual behaviour is a rewarding behaviour with ejaculation being the most reinforcing component. However, the neural pathways that process and relay ejaculation-specific sensory information and mediate sexual reward are currently unknown. A candidate spinothalamic pathway has recently been discovered to be in the position to process and relay ejaculatory-related cues from the reproductive organs to the brain. This pathway consists of a population of lumbar spinothalamic cells projecting to an area of the thalamus, known as the medial parvocellular subparafascicular thalamic nucleus, and expresses several neuropeptides, including galanin and cholecystokinin. The current study demonstrates that this spinothalamic pathway and …

The Production Of Multiform Narratives In The Heterotopic Space Of Technoscience: A Critical Instance Case Study Of A Western Canadian Genomics Research Facility, Cameron Michael Murray

Digitized Theses

Broadly speaking, this thesis explores the practices used by employees of a Western Canadian genomics research facility to build four-dimensional models of the human body; models which will be used to study genetic diseases. Usiiig actor-network theory as both a theoretical and methodological foundation, I consider the ways in which both the social (human) and the technical (nonhuman) actors that comprise the genomics research facility work together to construct these models. The work is divided into two sections. First, I investigate the setting of the genomics research facility. I argue that the genomics research facility constitutes a heterotopic site of …

Effects Of Diet And Abiotic Conditions On Male Sex Phermone Content, And The Importance Of Male Pheromones In Male Mating Success In The True Armyworm, Pseudaletia Unipuncta, Qi Xiu (Gordon) Chen

Digitized Theses

Males of the true armyworm, Pseudaletia unipuncta, release sex pheromones from bilateral hairpencils, so fluctuating asymmetry (FA) of the pheromone source and concentration may be important in female choice. A survey of the field caught true armyworm males showed high inter-male variability in both concentration and FA from July 12toAugust5.1alsoquantifiedpheromonesofmalesfedonartificialdietorcom leaves during larval development when reared under controlled laboratory and fluctuating field conditions. Again I found that both larval diet and abiotic conditions could influence both pheromone concentration and FA. Newly-emerged males reared under field condition had more pheromones and were more symmetrical than ones reared under controlled laboratory conditions …

Effects Of Dietary Selenium On The Health And Survival Of Wintering Lesser Scaup, Caroline M. Brady

Digitized Theses

The acquisition and accumulation of selenium (Se) in the Lower Great Lakes (LGL) could be contributing to the continental decline of lesser and greater scaup (Aytha qffinis, A. marila). I exposed lesser scaup to background (0.8 ¿¿g/g), moderate (8.1 jUg/g) and high (20.7 jug/g) levels of dietary Se, measured survival rates and several indices of health in relation to hepatic Se concentrations. There was 100% survival of scaup exposed to Se for 10-weeks (staging duration) but birds in the high treatment group had lower lipid reserves. There was 93% survival after 23-weeks (wintering duration), but no differences among treatment groups …

The Role For Shroom3 In The Cellular And Molecular Mechanisms Of Linear Heart Tube Formation, Stephanie A. Grover

Digitized Theses

Cardiac morphogenesis requires coordination of cell morphogenesis but how this coordination is achieved is not well understood. The objective of this study is to elucidate the underlying mechanisms of heart tube formation in Xenopus laevis. I hypothesized that Shroom3, an actin binding protein needed for neural tube closure, is also used in heart tube formation. I demonstrate that Shroom3 is indeed necessary for heart tube formation. Without Shroom3 activity, hearts are shorter and fail to form a proper tube. In the forming heart tube, there is a basal movement of nuclei and cell thickening that requires Shroom activity. The apical …

The Effects Of Visual Cues On The Collisions Of Free-Flying Myotis Lucifugus With Obstacles, Dara Nicole Orbach

Digitized Theses

Free-flying insectivorous bats occasionally collide with stationary objects that they should easily detect. These collisions often occur when lights are on suggesting that bats that collide may attend to visual sensory input over echolocation. To investigate the role of visual cues on the collisions of free-flying Myotis lucifugus with stationary objects, I set up obstacles at an Ontario swarming site. I used combinations of light intensities, obstacle fabrics that were not visually alike, and conspecific distress calls to verify that the bats in my study were not distracted by distress calls, and appeared to orient by vision when visual cues …

The Effects Of Dietary Fatty Acids On Avian Migratory Performance, Edwin Rockwell Price

Digitized Theses

Migratory birds use fat nearly exclusively to fuel their long distance movements. Little is known about how different types of fat affect their migratory performance, although dietary fats have been hypothesized to affect exercise through their roles as both oxidative substrates and membrane components. This thesis investigated the effects of fatty acids on avian flight performance and evaluated these two hypothesized mechanisms. I first investigated the selective mobilization of fatty acids from avian adipocytes. Unsaturated fatty acids and short chain fatty acids were most readily mobilized from avian adipocytes, indicating they may be important in increasing maximal metabolic rates. Further, …

The Influence Of Soil Amendments (Coal Fly Ash, And Stabilized Biosolids) On The Plant Parasitic Nematode Meloidogyne Hap\A\ Including Free Living Nematodes, Microbes And Soil Chemical Properties, Pablo Jaramillo

Digitized Theses

Field and greenhouse soil studies were designed to test the effect of stabilized biosolids and coal fly ash as management on the plant-parasitic nematode Meloidogyne hapla. The trials were conducted in a Bryanston silt loam in Southwestern Ontario formed on a calcareous substrate. Fly ash was obtained from the Lambton Generating station in Sarnia, Ontario and stabilized biosolids from lagoons at Glencoe, Ontario. Field and greenhouse crops included carrot (Daucus carota L.) and tomato (Lycopersicon esculentum Mill), each grown from seeds. Amendment ratios of biosolids and fly ash and application rates were established based on international guidelines and previous studies …

Evaluation Of The Harlequin/.Big Blue® Mouse As A Model For Studies Of Elevated Oxidative Stress And In Vivo Mutation Detection, Rory A. Crabbe

Digitized Theses

The harlequin (hq)/Big Blue® mouse, a novel model of oxidative stress- induced heart disease with transgene targets for assay of in vivo mutations, was used to assess the effects of elevated reactive oxygen species (ROS) on mutagenesis in the heart. The e ll transgene was used as the mutation target given the detection of a germline mutation in the lacltransgene. Mutations were examined 15 days following a single i.p. injection of the ROS producer, paraquat (10mg/kg) or vehicle control in adult hq/Big Blue® and wild type mice. Despite elevated endogenous superoxide anion levels in heart tissue from hq mice, the …

Framework Establishment Of Transgenic Plantae Facilitating Systemic Delivery Of Glucagon-Like Peptide-1 (Glp-1), Martin E. Brandsma

Digitized Theses

Human serum transferrin (hsTf) is well characterized for its ability to transport fused therapeutics throughout the body upon oral administration. Glucagon-like peptide-1 (GLP-1) is one such therapeutic, effective against Type II diabetes that could benefit from such a fusion strategy. However, therapeutic use of hsTf and GLP-1 is limited by their generation using current recombinant protein production platforms. This project assesses the viability of accumulating hsTf and GLP-1 independently in transgenic plants as a novel source for the generation o f both recombinant proteins. Here, nuclear-transformed tobacco plants stably accumulating either hsTf or a synthetic GLP-1 decamer have been developed. …

Factors Influencing Utilization Of Artificial Nesting Cylinders By Mallards And Wood Ducks In Northwest Pennsylvania And Southern Ontario, Jeremy J. Stempka

Digitized Theses

Factors influencing utilization of elevated nesting structures by waterfowl were examined in southern Ontario and northwest Pennsylvania, 2006-2008. In the final-year, Mallard occupancy rates were 18 % in Pennsylvania and 16 % in Ontario. Mean nest success was 77 ± 20 % for combined sites (2006-2008). Final-year Wood Duck occupancy rates were 12 % in Pennsylvania and 2 % in Ontario; mean nest success was 70 ± 29 %. Mallards tended to select structures in areas with high wetland densities and adjacent to grasslands or hayfields. In Pennsylvania, Wood Ducks had similar preferences for structures as did Mallards. In Ontario, …

Gata6 Induces Wnt6 Expression During Primitive Endoderm Differentiation, Jason T.K. Hwang

Digitized Theses

Mouse F9 teratocarcinoma cells in culture differentiate into primitive endoderm when treated with retinoic acid and into parietal endoderm with subsequent treatment with dibutyryl cAMP. This in vitro model has been studied extensively as these chemically induced events mimic one o f the earliest epithelial-to-mesenchymal transitions in mouse embryogenesis. During differentiation to primitive endoderm Wnt6 expression is up- regulated by RA, and the result is the activation o f the canonical W nt/p-catenin signaling pathway. The factor(s) responsible for the activation o f the Wnt6 gene is not known, but in silico analysis reveals that its promoter region contains a …

High Duty Cycle Echolocation And Prey Detection Ability In Bats, Louis Lazure

Digitized Theses

While most echolocating bats separate pulse and echo in time (low duty cycle bats), a few species separate pulse and echo in frequency (high duty cycle). The type of écholocation is defined by the pattern of signal emission, but many other call variables differ significantly between the two approaches. This study used two complementary experiments to understand the role of flying prey detection ability as a selective force that could explain the diversity of écholocation behaviour in extant bats. I collected data from acoustical measurements of artificial sonar echoes from fluttering targets, and field recordings of hunting behaviour of different …

Herbivory And Detritivory By The Land Snail Cepaea Nemoralis In A Temperate Old Field, Paul J. Mensink

Digitized Theses

The European banded wood snail (Cepaea nemoralis) has become widespread throughout the northeast United States and Canada, thriving in woodlands, roadsides, disturbed habitats, grasslands, and old fields. I used exclosure experiments to investigate the effect of snail herbivory on the biomass of Canada thistle (Cirsium arvense), a highly palatable forb species. I measured grass litter within exclosures to determine the effects o f detritivory on litter mass and used fecal analysis to determine the ratio of dead to live plant material in the diet. Snail exclosures had no effect on the total biomass of C. arvense or mass of grass …

Gene Discovery In Schizophrenia Through Identification Of Copy Number Variations (Cnvs) In Discordant Monozygotic (Mz) Twins, Christina Angela Castellani

Digitized Theses

Schizophrenia (MIM 181500) is a complex and devastating human disease that affects greater than 1% of the population (Huxley et al., 1964). The disease has a heritability of 80%, but a concordance rate in monozygotic (MZ) twins of only 48% (Gottesman, 1991). This suggests a role for both genetics and random/environmental factors in the etiology of this complex disorder (Singh et al., 2009). Copy Number Variation (CNV) is now a known candidate for disease associated variation in humans. CNVs have been identified as a common feature covering 12% of the genome in normal, healthy individuals (Feuk et al., 2006; Redon …

Gata6 Induces Wnt6 Expression During Primitive Endoderm Differentiation, Jason T.K. Hwang

Digitized Theses

Mouse F9 teratocarcinoma cells in culture differentiate into primitive endoderm when treated with retinoic acid and into parietal endoderm with subsequent treatment with dibutyryl cAMP. This in vitro model has been studied extensively as these chemically induced events mimic one of the earliest epithelial-to-mesenchymal transitions in mouse embryogenesis. During differentiation to primitive endoderm Wnt6 expression is up- regulated by RA, and the result is the activation ofthe canonical Wnt/p-catenin signaling pathway. Thefactor(s)responsiblefortheactivationoftheWnt6geneisnotknown,but in silico analysis reveals that its promoter region contains a putative binding site for the transcription factor GATA6. In this study, the expression of Gata6 following retinoic acid …

Identity And Diversity Of Agaricomycetes (Fungi: Basidiomycota) In Temperate Agricultural Soils, Barbara D. Bahnmann

Digitized Theses

The objectives of this study were to identify and to compare the species richness, community composition and genetic diversity of Agaricomycetes in Michigan agricultural soils. Ribosomal DNA sequences were obtained from soils in four treatments: conventional till monocrop, no-till monocrop, historically tilled grassland and never-tilled grassland. The Agaricales dominated the community, with 85 % of all detected taxa. The taxonomic composition of conventional till plots was different from other plots due to the high prevalence of Pneumatospora (Cantharellales) and Lachnella/Calathella (Agaricales) clades and the absence of Hygrocybe (Agaricales) and Polyporales clades. These latter clades dominated less disturbed treatments. Genetic diversity …

Comparative Study Of A Novel Membrane Bioreactor System For Biological Nutrient Removal With Conventional Systems, Mingu Kim

Digitized Theses

This comparative study evaluated a novel membrane bioreactor (NMBR) for biological nutrient performance and membrane fouling with conventional BNR systems i.e. anaerobic/anoxic/aerobic (A O) process and University of Capetown (UCT) modified MBR process (UMBR). Comparison of the NMBR and A20 process, conducted at hydraulic retention time (HRT) of 8 hr and solids retention time (SRT) of 10 days using synthetic wastewater (SWW) and municipal wastewater (MWW), revealed that NMBR achieved lower effluent phosphorus than the A O with 0.2 vs 1.2 mg/L (SWW) and 0.8 vs 1 mg/L (MWW) as well as 20% lower sludge production. The study also substantiated …

Visible Wavelength Maldi Study, Chunyan Yang

Digitized Theses

Since its inception over two decades ago matrix-assisted laser/desorption ionization (MALDI) mass spectrometry (MS) using either ultraviolet (UV) or infrared (IR) lasers, has become an important tool for the analysis of molecules of chemical and biological interest. Primarily, this is because MALDI-MS is a relatively "soft methodology which allows the ionization and detection of intact analytes with minimal fragmentation. Although MALDI mass spectrometry using visible wavelength lasers has been less studied it is expected to have several advantages over UV-MALDI and IR- MALDI. Many macromolecules of interest absorb UV-light but are transparent at visible wavelengths. In principle, visible-MALDI should be …

Interactive Effects Of Warming And Atmospheric Nitrogen Deposition On Plant Net Productivity And Species Composition In A Temperate Old Field, Jennifer S. Hutchison

Digitized Theses

Both climate warming and atmospheric nitrogen deposition are predicted to alter plant productivity and species composition over the next century; however, the extent to which their effects may interact is unclear. I measured plant productivity and species composition in response to warming (winter-only or year-round) and nitrogen in a temperate old field. I used shoot allometric relationships and spectral data to estimate productivity non-destructively, and sampled root biomass destructively, throughout two growing seasons. In 2007 there were no treatment effects on plant growth. However, in 2008, both warming and nitrogen addition increased aboveground productivity, and these effects were additive, resulting …

Involvement Of Fzd7 Signaling In Extraembryonic Endoderm Differentiation, Ben H. Cadesky

Digitized Theses

The mouse F9 teratocarcinoma cell line is used to mimic primitive endoderm differentiation and the subsequent parietal endoderm differentiation seen in vivo during early mouse development. This is achieved by treating undifferentiated F9 cells with the morphogen retinoic acid (RA) to form primitive endoderm and with RA and dibutyryl cyclic AMP to form parietal endoderm. The in vitro F9 model has been studied extensively because the differentiation from primitive to parietal endoderm is one of the earliest epithelial-to-mesenchymal transitions seen in mouse development. RA has been shown to upregulate Wnt6 in F9 cells, which signals through the canonical (3-catenin pathway. …

Affective Decision-Making Predictive Of Chinese Adolescent Drinking Behaviors, Lin Xiao, Antoine Bechara, Jerry L. Grenard, Alan W. Stacy, Paula Palmer, Yonglan Wei, Yong Jia, Xiaolu Fu, C. Anderson Johnson

CGU Faculty Publications and Research

The goal of the current investigation was to address whether affective decision making would serve as a unique neuropsychological marker to predict drinking behaviors among adolescents. We conducted a longitudinal study of 181 Chinese adolescents in Chengdu city, China. In their 10th grade (ages 15–16), these adolescents were tested for their affective decision-making ability using the Iowa Gambling Task (IGT) and working memory capacity using the Self-Ordered Pointing Test. Self-report questionnaires were used to assess academic performance and drinking behaviors. At 1-year follow-up, questionnaires were completed to assess drinking behaviors, and the UPPS Impulsive Behavior Scale was used to examine …

Forest Health Monitoring (Trees) In The Gordon Natural Area, Gerard Hertel

Forest Health Monitoring Study Documents

No abstract provided.

Rcmat: A Regularized Covariance Matrix Approach To Testing Gene Sets, Phillip D. Yates, Mark A. Reimers

Biostatistics Publications

Background Gene sets are widely used to interpret genome-scale data. Analysis techniques that make better use of the correlation structure of microarray data while addressing practical "n

Results We evaluated our testing procedure using both simulated data and a widely analyzed diabetes data set. We compared our approach to another popular multivariate test for both sets of data. Our results suggest an increase in power for detecting gene set differences can be obtained using our approach relative to the popular multivariate test with no increase in the false positive rate.

Conclusion Our regularized covariance matrix multivariate approach to gene set …