Life Sciences Commons^™

Urologist Burnout: Frequency, Causes, And Potential Solutions To An Unspoken Entity, Julie Franc-Guimond, Brian Mcneil, Steven M. Schlossberg, Amanda C. North, Alp Sener

Anatomy and Cell Biology Publications

Physician burnout has been linked to decreased job performance, increased medical errors, interpersonal conflicts, and depression. Recent multispecialty studies suggest that urologists have higher rates (up to 63.6%) of burnout compared to physicians in other specialties; however, these reports were limited by low sample sizes.1 We aimed to evaluate the prevalence of urologist burnout, verify risk factors, and recommend preventative measures and solutions for colleagues at risk or suffering from burnout. Urologist burnout is a true entity that transcends level of training and nationality. Its roots appear to be deep-seated in our tireless efforts to strive for excellence in care …

Resource Selection, Survival, And Departure Of Adult Female Mallards From The Lake St. Clair Region During Autumn And Winter, Matthew Palumbo

Electronic Thesis and Dissertation Repository

During autumn and winter, mallards (Anas platyrhynchos) maximize fitness through their spatiotemporal distribution to avoid mortality risks while balancing trade-offs to access foods to undergo migration and maintain homeostasis. Thousands of mallards use Lake St. Clair as it is an important, but threatened, migratory staging area in the Great Lakes. My goal was to understand how mallards were selecting resources in the region and potential relationships of selection strategies. My objectives were to estimate resource selection of adult female mallards, in relation to perceived risk of hunting mortality, and determine if selection strategies were related to survival and …

Investigating The Regulatory Circuitry Of Protein Kinases And Proteases In Apoptosis, Stephanie A. Zukowski

Electronic Thesis and Dissertation Repository

Apoptosis is a tightly regulated cellular process essential for normal development and tissue homeostasis. Perturbations to apoptotic signaling underscores numerous pathogenic processes emphasizing the importance of apoptotic regulation. During apoptosis, caspases orchestrate cellular degradation through proteolytic cleavage of key structural and enzymatic proteins. In a different manner, protein kinases regulate apoptosis by catalyzing the post-translational phosphorylation of substrate proteins to facilitate either pro- or anti-apoptotic signal transduction pathways. Emerging paradigms have indicated that bidirectional crosstalk between protein kinases and caspases serves to globally fine-tune the equilibrium between signals directing cell survival and cell death. In this regard, identifying points of …

Regulation Of Liver Mitochondrial Metabolism During Hibernation By Post-Translational Modification, Katherine E. Mathers

Electronic Thesis and Dissertation Repository

Hibernation, characterized by a seasonal reduction in metabolism and body temperature, allows animals to conserve energy when environmental conditions (e.g. temperature, food availability) are unfavourable. During hibernation, small mammals such as the 13-lined ground squirrel (Ictidomys tridecemlineatus) cycle between two distinct metabolic states: torpor, where metabolic rate is suppressed by >95% and body temperature falls to ~5 °C, and interbout euthermia (IBE), where metabolic rate and body temperature rapidly increase and are maintained at euthermic levels several hours. Suppression of metabolism during entrance into torpor is paralleled by rapid suppression of liver mitochondrial metabolism. In my thesis, I …

Correction Of Dna Sequencing Data With Spaced Seeds, Stephen Lu

Electronic Thesis and Dissertation Repository

The advent of next-generation sequencing technologies has allowed for the bridging of wet lab work and large data analysis into a cohesive work flow; with the increasing speed and efficiency of sequencing organisms, it becomes imperative that we are able to ensure the data that is produced is correct.

We designed and implemented a new algorithm, QUESS, which based on using multiple spaced seeds to correct DNA sequencing data from Illumina MiSeq, HiSeq and NextSeq machines using C++ and OpenMP for parallel computing. We compared our method with ten leading programs, producing consistently better overall results for most tested measures. …

Role Of Asparagine As A Nitrogen Signal And Characterization Of A Nitrogen Responsive Glutamine Amidotransferase, Gat1_2.1 In Arabidopsis Thaliana, Shrikaar Kambhampati

Electronic Thesis and Dissertation Repository

Maintaining the proper balance between carbon (C) and nitrogen (N) metabolism is critical to the sustained growth of organisms. In plant leaves, this balance is achieved by photoperiod dependent cross-talk between the processes of photosynthesis, respiration, and amino acid metabolism. A crucial mechanism in maintaining C/N balance is the GS/GOGAT cycle, which is well known to serve as a cross-road between C and N metabolism. Importantly, non-photosynthetic tissues (e.g. roots, germinating seeds) lack a sufficient supply of carbon skeletons under high N conditions and hence may resort to other mechanisms, along with the GS/GOGAT cycle, to achieve proper C/N balance. …

Nutritional Regulation Of Sulfonamide Antibiotic Biodegradation By Microbacterium Sp. Strain C448, Tonya Malcolm

Electronic Thesis and Dissertation Repository

Sulfonamide antibiotics are frequently released into the environment due to their widespread use in livestock production, imposing a potential selection pressure for the development and dissemination of sulfonamide resistance. Recently, a sulfonamide-degrading bacterium Microbacterium sp. Strain C448 was discovered, whose activity has the potential to be used as a sulfonamide removal strategy from agricultural soils. This research gains insight into the sulfonamide biodegradation pathway by 1) evaluating the nutritional regulation of sulfamethazine biodegradation and 2) undertaking a comparative proteomic analysis of cells grown in the presence and in the absence of sulfamethazine. The nutritional analyses revealed that increasing amounts of …

Identification And Characterization Of Farr And Fare As A Regulator And Effector Of Fatty Acid Resistance In Staphylococcus Aureus, Heba Alnaseri

Electronic Thesis and Dissertation Repository

Although Staphylococcus aureus is exposed to antimicrobial fatty acids on the skin, in nasal secretions and in abscesses, specific mechanisms for regulating gene expression and intrinsic resistance in response to these fatty acids have not been reported. Through in vitro selection for increased resistance of S. aureus to linoleic acid, I identified fatty acid resistant clone FAR7, where a single nucleotide polymorphism caused a His₁₂₁Tyr substitution in an uncharacterized member of the TetR family of transcriptional regulators, which is divergently transcribed from a gene encoding a member of the resistance-nodulation-division superfamily of multi-drug efflux pumps. I named these …

Characterizing The Interaction Between Human Adenovirus E1a And Sting, Jessica Hill

Electronic Thesis and Dissertation Repository

When challenged by viral DNA, the cytoplasmic DNA sensor cyclic GMP-AMP synthase (cGAS) signals through the adaptor protein stimulator of interferon genes (STING) to induce a primary type I IFN response. Studies from recent years have also revealed shared architecture between metabolism and innate immunity. Viruses have evolved to counteract these mechanisms. Human adenovirus (HAdV) early region 1A (E1A) protein antagonizes the cGAS-STING pathway to prevent an innate immune response by physically interacting with STING. I hypothesize that the interaction between E1A and STING is mediated through several motifs and involves ribosomal protein S6 kinase beta-1 (S6K1). Using a series …

Chromatin Accessibility Dynamics In The Arabidopsis Root Epidermis And Endodermis During Cold Acclimation, Shawn Hoogstra

Electronic Thesis and Dissertation Repository

Understanding cell-type specific transcriptional responses to environmental conditions is limited by a lack of knowledge of transcriptional control due to epigenetic dynamics. Additionally, cell-type analyses are limited by difficulties in applying current technologies to single cell-types. A novel DNase-seq protocol and analysis procedure, deemed DNase-DTS, was developed to identify DHSs in the Arabidopsis epidermis and endodermis under control and cold acclimation conditions. Results identified thousands of DHSs within each cell-type and experimental condition. DHSs showed strong association to gene expression, DNA methylation, and histone modifications. A priori mapping of existing DNA binding motifs within accessible genes and the cold C-repeat/dehydration …

Characterizing Mekk1: Candidate Behavioural Isolation Gene, Caryn Dooner

Electronic Thesis and Dissertation Repository

Behavioural isolation can occur due to divergence in aspects of courtship and mating, and can contribute to reproductive isolation. The purpose of this study is to determine how a gene, Mekk1, contributes to female rejection behaviour between D. melanogaster and D. simulans. Unique polymorphisms were identified within D. simulans Mekk1 that could contribute to behaviour, most of which are non-coding. Both transcripts of Mekk1 appear to be expressed at similar levels in D. simulans and D. melanogaster. These data also indicate that Mekk1 may be expressed in a specific region of the brain called the mushroom body, …

Power Reserve Following Ramp-Incremental Cycling To Exhaustion: Implications For Muscle Fatigue And Function, Michael D. Hodgson

Electronic Thesis and Dissertation Repository

In ramp-incremental cycling exercise, some individuals are capable of producing power output (PO) in excess of that produced at their limit of tolerance (LoT) while others cannot. This study sought to describe the: 1) prevalence of a “power reserve” within a group of young men (n=21; mean ± SD: age 25±4 years; V̇O_2max45±8 ml•kg^-1•min^-1); and 2) muscle fatigue characteristics of those with and without a power reserve. Power reserve was determined as the difference between peak PO achieved during a ramp-incremental test to exhaustion and maximal, single-leg isokinetic dynamometer power. Pre- versus post-exercise changes …

Nbpmf: Novel Network-Based Inference Methods For Peptide Mass Fingerprinting, Zhewei Liang

Electronic Thesis and Dissertation Repository

Proteins are large, complex molecules that perform a vast array of functions in every living cell. A proteome is a set of proteins produced in an organism, and proteomics is the large-scale study of proteomes. Several high-throughput technologies have been developed in proteomics, where the most commonly applied are mass spectrometry (MS) based approaches. MS is an analytical technique for determining the composition of a sample. Recently it has become a primary tool for protein identification, quantification, and post translational modification (PTM) characterization in proteomics research. There are usually two different ways to identify proteins: top-down and bottom-up. Top-down approaches …

Exploiting Fission Yeast Genetic Interaction Data To Identify Disease-Specific Drug Targets For Tuberous Sclerosis Complex, Ashyad Rayhan

Electronic Thesis and Dissertation Repository

Tuberous sclerosis complex (TSC) is an inherited genetic disorder caused by loss-of-function mutations in either TSC1 or TSC2. Their respective gene products regulate the mechanistic target of rapamycin (mTOR) signaling pathway, which serves as an activator of cellular proliferation, metabolism, and cell survival. Orthologs of the TSC1 and TSC2 genes exist in a wide range of organisms, including the commonly used and genetically tractable model eukaryote, Schizosaccharomyces pombe. To better understand the functional roles of S. pombe tsc1 and tsc2, I exploited recent advances in genetic interaction biology to identify and characterize genes that modulate the phenotypic …

Oculomotor Executive Dysfunction During The Early And Later Stages Of Sport-Related Concussion Recovery, Brandon Webb

Electronic Thesis and Dissertation Repository

Executive dysfunction represents a persistent concussion deficit; however, it is largely unclear whether the deficit persists in an athlete after they have been deemed safe to return to play. In the present work, athletes with a sport-related concussion, and their age- and sex-matched controls, completed prosaccades and executive-related antisaccades: (1) 2-6 days post-concussion (i.e., initial assessment), and (2) 14-20 days after initial assessment and only when an athlete was medically cleared for safe return to play (i.e., follow-up assessment). Initial assessment antisaccades for the concussed group produced longer reaction times (RT) and more directional errors than the control group. The …

Effect On Pellicle Proteome Upon Adsorption Of Salivary Peptide On Hydroxyapatite And Their Effects On Enamel Demineralization, Rajesh Kr. Gupta

Electronic Thesis and Dissertation Repository

According to WHO, oral health is an important indicator of overall health. Poor oral health cause serious health problems (cardiovascular, stroke, diabetes, liver, and respiratory related), in different age groups, costing billions of dollars. So, proper oral health care management has assumed top priority. Salivary antimicrobial peptides (histatin and statherin), are part of enamel pellicle, required for the oral homeostasis. Current work focused to study the demineralization protection and pellicle proteome modulation capabilities of novel peptide constructs (single and tandem duplicate histatin constructs DR9, DR9-DR9 and histatin-statherin hybrid construct DR9-RR14). For the first time, we provided evidence that, these peptide …

Error Correction And De Novo Genome Assembly Of Dna Sequencing Data, Michael Z. Molnar

Electronic Thesis and Dissertation Repository

The ability to obtain the genetic code of any species has caused a revolution in biological sciences. Current technologies are capable of sequencing short pieces of DNA with very high quality. These short pieces of DNA determint the sequence of bases in the genome of any species. This information is key in understanding many of the aspects of how life functions.

The accuracy of sequencing is extremely important since the differences between individuals of the same species are caused by very few changes. All sequencing technologies make errors, and before the data can be used for downstream applications it is …

Relative Attraction Of The Cabbage Looper Moth (Trichoplusia Ni (Hübner)) To Wild-Type And Transgenic Tomato (Solanum Lycopersicum L.), William J. Laur

Electronic Thesis and Dissertation Repository

The cabbage looper moth (CLM), Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) is an agricultural pest that has developed resistance to many frequently used insecticides, so alternative methods are required to reduce greenhouse CLM populations. Host plant volatile organic chemicals (VOCs) are used by female CLMs as cues for host location and oviposition. I hypothesized that changes in host plant VOC production, through genetic modification, could alter host location behaviour by CLMs. These changes in VOCs have potential to give rise to highly attractive transgenic trap crops. Chemical analyses on genetically transformed tomato, Solanum lycopersicum L. plants provided evidence of different VOCs …

Gene Expression Changes In The Mushroom Body Of Drosophila Melanogaster During A Time Course Of Long-Term Memory Formation And Maintenance, Spencer G. Jones

Electronic Thesis and Dissertation Repository

Long-term memory (LTM) requires gene transcription. However, there is still much to learn about which genes are transcriptionally regulated during LTM and the biological roles they play. Here, gene expression changes were characterized in Drosophila melanogaster over a time course of LTM formation and maintenance in neurons of the mushroom body (MB), a structure required for normal learning and memory. I identified 120 genes differentially expressed (q < 0.2, fold change > 1.3) 24h after LTM induction. Among these were 13 potential downstream targets for RNA localization by the known memory genes pumilo, staufen and oskar, several genes encoding chromatin regulators and seven genes with …

The Feasibility Of Square-Stepping Exercise As A Universal Intervention For Older Adults With Chronic Disease To Improve Cognitive And Physical Function, Erin M. Shellington

Electronic Thesis and Dissertation Repository

Square-stepping exercise (SSE) is a cognitive training program with a physical component. An instructor demonstrates a stepping pattern across a gridded mat and participants are required to memorize and repeat the patterns on their own. In community-dwelling older adults, SSE has demonstrated some benefits on global cognitive functioning (GCF), balance, functional fitness, and social interaction.

Aims: to investigate the feasibility and efficacy of SSE in varied populations and settings to improve mobility and cognition. Populations included older adults with: knee osteoarthritis (OA), type 2 diabetes mellitus (T2DM) and self-reported cognitive complaints (sCC), and those living in long-term care (LTC) …

Characterization Of Six Arabidopsis Arogenate Dehydratase Promoters, Emily J. Cornelius

Electronic Thesis and Dissertation Repository

Phenylalanine is an important aromatic amino acid synthesized by higher plants, and is a major component of numerous specialized metabolites including structural components, pigments, and defense compounds. The last step in the synthesis of phenylalanine is catalyzed by an enzyme called AROGENATE DEHYDRATASE, of which there are six different isoenzymes encoded by the Arabidopsis genome. All six have specialized roles within the plant, and are differentially expressed during development and under stressful conditions. To deduce the specialized role of each ADT, unique patterns of regulatory motifs were identified for all six ADT promoters, as well as corresponding transcription factors with …

Identification Of Novel Binding Partners And Substrates Of Histone H3k4 Specific Demethylase Kdm5b/Jarid1b, Qi Fang

Electronic Thesis and Dissertation Repository

It has been 50 years since the first histone methylation was identified. From then, numerous studies have verified that histone methylation neutralizes the positive charges of lysine, alters chromatin architectures, and recruits other DNA binding complexes. In this study, we examined the molecular basis of a histone demethylase – KDM5B in both its substrate and binding machineries. We hypothesized that KDM5B has alternative binding partners and substrates besides its known target H3K4me3. By utilizing biochemical approaches such as in vitro pull-down assays and fluorescence polarization assays, we were able to identify potential KDM5B binding partners – H2BK43me0/2. Also, we reinvestigated …

The Anatomy Of The Infrarenal Lumbar Splanchnic Nerves In Human Cadavers: Implications For Retroperitoneal Nerve-Sparing Surgery, Tyler Beveridge, Dale Fournier, Adam M.R. Groh, Marjorie Johnson, Nicolas E. Power, Brian L. Allman

Anatomy and Cell Biology Publications

Injury to the nerves of the aortic- and superior hypogastric plexuses during retroperitoneal surgery often results in significant post-operative complications, including retrograde ejaculation and/or loss of seminal emission in males. Although previous characterizations of these plexuses have done well to provide a basis for understanding the typical anatomy, additional research into the common variations of these plexuses could further optimize nerve-sparing techniques for retroperitoneal surgery. To achieve this, the present study aimed to document the prevalence and positional variability of the infrarenal lumbar splanchnic nerves (LSNs) through gross dissection of 26 human cadavers. In almost all cases, two LSNs were …

Multiparametric Mri Changes Persist Beyond Recovery In Concussed Adolescent Hockey Players, Kathryn Y. Manning Msc, Amy Achranz Bmsc, Robert Bartha Phd, Gregory A. Dekaban Phd, Christy Barreira Bsc, Arthur Brown Phd, Lisa Fischer Md, Kevin Asem Md, Timothy J. Doherty, Douglas D. Fraser Md Phd, Jeff Holmes Phd, Ravi S. Menon

Anatomy and Cell Biology Publications

Objective: To determine whether multiparametric MRI data can provide insight into the acute and long-lasting neuronal sequelae after a concussion in adolescent athletes.

Methods: Players were recruited from Bantam hockey leagues in which body checking is first introduced (male, age 11–14 years). Clinical measures, diffusion metrics, resting-state network and region-to-region functional connectivity patterns, and magnetic resonance spectroscopy absolute metabolite concentrations were analyzed from an independent, age-matched control group of hockey players (n 5 26) and longitudinally in concussed athletes within 24 to 72 hours (n 5 17) and 3 months (n 5 14) after a diagnosed concussion.

Results: …

Disruption Of Hippocampal Multisynaptic Networks By General Anesthetics., Min-Ching Kuo, L Stan Leung

Physiology and Pharmacology Publications

BACKGROUND: Previous studies showed that synaptic transmission is affected by general anesthetics, but an anesthetic dose response in freely moving animals has not been done. The hippocampus provides a neural network for the evaluation of isoflurane and pentobarbital on multisynaptic transmission that is relevant to memory function.

METHODS: Male Long-Evans rats were implanted with multichannel and single electrodes in the hippocampus. Spontaneous local field potentials and evoked field potentials were recorded in freely behaving rats before (baseline) and after various doses of isoflurane (0.25 to 1.5%) and sodium pentobarbital (10 mg/kg intraperitoneal).

RESULTS: Monosynaptic population excitatory postsynaptic potentials at the …

The Influence Of Limb And Target Vision In Target-Directed And Allocentric Pointing Movements, Joseph Manzone

Electronic Thesis and Dissertation Repository

The top-down nature of allocentric spatial representations (i.e., specifying target locations relative to other objects) is thought to render motor output via an offline mode of control. The present experiment tested this hypothesis by providing detailed trajectory analyses of allocentric and target-directed reaching tasks performed with and without concomitant limb vision. Allocentric tasks required reaches to a location defined by the relationship between a target and reference stimulus, whereas target-directed tasks required reaches directly to a target. Target-directed limb visible trials showed the most effective online trajectory amendments compared to their limb occluded counterparts and allocentric limb visible and occluded …

Assessing Landscape Effects On Genetics And Dispersal Of The Rocky Mountain Apollo Butterfly Parnassius Smintheus Using A Resistance Mapping Approach, Ning Chen

Electronic Thesis and Dissertation Repository

Landscape variables that best explain genetic differentiation may not also best explain dispersal patterns, but many studies use genetic differentiation as a proxy for dispersal. I tested the effects of landscape on both genetic differentiation and dispersal in parallel, to explore whether landscape effects on genetic differentiation between populations and landscape effects on dispersal would be comparable in such contexts. I used circuit theory (Circuitscape) and least cost transect analysis to evaluate the effects of landscape on both movement and genetic differentiation of the butterfly, Parnassius smintheus, in the Jumpingpound Ridge study system. Circuit theory and least cost transect …

Investigating Cognitive Control And Task Switching Using The Macaque Oculomotor System, Jason L. Chan

Electronic Thesis and Dissertation Repository

Cognitive control is crucial to voluntary behaviour. It is required to select appropriate goals and guide behaviour to achieve the desired outcomes. Cognitive control is particularly important for the ability to adapt behaviour to changes in the external environment and internal goals, and to quickly switch between different tasks. Successful task switching involves a network of brain areas to select, maintain, implement, and execute the appropriate task. Uncovering the neural mechanisms of this goal-directed behaviour using lesions, functional neuroimaging, and neurophysiology studies is central to cognitive neuroscience.

The oculomotor system provides a valuable framework for understanding the neural mechanisms of …

Evaluation Of A Microalgal Bioassay Based On Community Level Physiological Profiling (Clpp), Jun-Woo Kim

Electronic Thesis and Dissertation Repository

This thesis examined the use of commercially available Biolog 96-well plates containing different carbon sources for a microalgal bioassay. Quaternary ammonium compounds (QACs) were used as potentially toxic model compounds to demonstrate the applicability of the assay. Toxicity of dodecyl trimethyl ammonium chloride (DTAC) and didecyl dimethyl ammonium bromide (DDAB) on the growth of Scenedesmus obliquus varied significantly under autotrophic, heterotrophic and mixotrophic growth conditions. The concentration for 50% growth inhibition effect (EC₅₀) of DTAC followed the order: autotrophic (0.48 ± 0.03 mg of DTAC/L) > heterotrophic (1.46 ± 0.04 mg of DTAC/L) > mixotrophic (2.11 ± 0.06 mg of …

A Simulated Walk In Nature: Testing Predictions From The Attention Restoration Theory, Corey Crossan

Electronic Thesis and Dissertation Repository

Attention Restoration Theory (ART) predicts that top-down processing during everyday activities can cause attentional fatigue and that bottom-up processing that occurs when people experience nature will be restorative (Kaplan, 1995). The present study examined this prediction by exposing participants to three different conditions using a repeated measures design: a control condition during which participants walked on a typical treadmill, a nature/restorative condition during which participants walked on the same treadmill, experiencing a simulated nature walk, and a perturbation condition that included the same simulated nature scene but also required top-down processing during the walk. The findings supported ART predictions. As …