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2018

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Articles 12481 - 12510 of 12524

Full-Text Articles in Life Sciences

The Sidewalk Problem: An Examination Of The Avoidance Behaviours Employed During A Head-On Collision Course With An Approaching Person, Lana M. Pfaff Jan 2018

The Sidewalk Problem: An Examination Of The Avoidance Behaviours Employed During A Head-On Collision Course With An Approaching Person, Lana M. Pfaff

Theses and Dissertations (Comprehensive)

Individuals use visual information in order to guide their avoidance behaviours. More specifically, individuals may directly perceive the time prior to colliding with an approaching obstacle (i.e., time to contact, TTC) in order to determine when to avoid. However, if the path of the approaching obstacle is highly predictable, individuals do not use a consistent TTC (Cinelli & Patla, 2007). Additionally, individuals use body- and action-scaled information to control their movements (Fajen, 2013). These avoidance behaviours differ when avoiding a human obstacle compared to an inanimate object (Hackney, Cinelli, & Frank, 2015; Knowles, Kreuser, Haas, Hyde, & Schuchart, 1976). As …

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Spatial Modelling And Wildlife Health Surveillance: A Case Study Of White Nose Syndrome In Ontario, Lauren Yee Jan 2018

Spatial Modelling And Wildlife Health Surveillance: A Case Study Of White Nose Syndrome In Ontario, Lauren Yee

Theses and Dissertations (Comprehensive)

Wildlife data is often limited by survey effort, small sample sizes, and spatial biases associated with collection and missing data. These factors can create unique challenges from a surveillance perspective when trying to extract spatial patterns of habitat suitability and disease distributions for conservation and management purposes. This thesis examined data quality from a wildlife health database in the context of spatial analysis of wildlife disease. Spatial analysis of the data to predict habitat suitability of bats and white nose syndrome afflicted bats was examined by using the MaxEnt modelling method. Methods to reduce spatial bias were examined and specific …

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The Influence Of Physiological And Abiotic Factors On The Sensitivity Of The Sea Lamprey (Petromyzon Marinus) To The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm), Alexandra Muhametsafina Jan 2018

The Influence Of Physiological And Abiotic Factors On The Sensitivity Of The Sea Lamprey (Petromyzon Marinus) To The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm), Alexandra Muhametsafina

Theses and Dissertations (Comprehensive)

Invasive sea lamprey (Petromyzon marinus) in the Great Lakes are controlled using the pesticide (lampricide) 3-trifluoromethyl-4-nitrophenol (TFM), which is applied to nursery streams containing larval lamprey. The toxicity of TFM to lamprey is affected by various environmental and physiological factors, which can lead to residual lamprey that survive TFM treatment. The goal of this study was to investigate how abiotic (season and temperature) factors interacted with physiological parameters (whole body and tissue energy reserves) to influence TFM sensitivity in sea lamprey. Toxicity tests were conducted at different times of the year (spring, early and late summer, fall) and …

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The Influence Of Water Chemistry And Gill Physiology On The Uptake Of The Lampricide Tfm By Lake Sturgeon (Acipenser Fulvescens), Scott Leslie James Hepditch Jan 2018

The Influence Of Water Chemistry And Gill Physiology On The Uptake Of The Lampricide Tfm By Lake Sturgeon (Acipenser Fulvescens), Scott Leslie James Hepditch

Theses and Dissertations (Comprehensive)

Application of 3-trifluoromethyl-4-nitrophenol (TFM) to control invasive sea lamprey (Petromyzon marinus) within the Laurentian Great Lakes seldom causes non-target mortality. However, under certain conditions, TFM can harm species such as the lake sturgeon (Acipenser fulvescens). Lake sturgeon less than 100mm in length are particularly vulnerable to TFM-induced mortality, and are more sensitive to TFM toxicity with increasing water alkalinity as compared to sea lamprey. The objectives of this study were to evaluate the influence of pH and alkalinity on the uptake of TFM by juvenile sturgeon using radio-labeled TFM (14C-TFM). An additional objective was …

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Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister Jan 2018

Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is applied to tributaries of the Great Lakes to control invasive sea lampreys (Petromyzon marinus). Although TFM is selectively toxic to larval sea lampreys, non-target mortality can occur during lampricide treatments. It is important to know whether or not TFM played a role in the death of these fishes, and the most direct means to do this is using forensic science principles. The objectives of this study were to: (i) determine the acute toxicity of TFM to the non-target fishes, rainbow trout (Oncorhynchus mykiss) and white sucker (Catostomus commersonii), and how the lampricide is …

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Forensic Markers Of Lampricide Toxicity In Oncorhynchsus Mykiss, Chris White Jan 2018

Forensic Markers Of Lampricide Toxicity In Oncorhynchsus Mykiss, Chris White

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been used for decades to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, normally with little harm to other fish populations. However, due to the nature of lampricide treatments and the chemical properties of TFM, adverse effects to non-target fishes and non-target mortality occasionally occur. However, investigations of non-target mortality can be complex, particularly if fish deaths are not noticed immediately, due to decomposition of the carcasses. The objectives of this thesis were to expose rainbow trout (Oncorhynchsus mykiss) to TFM in order to: (i) identify forensic markers …

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Exploring The Relationship Between Group Cohesion And Compassion In Varsity Athletes, Theo Chu Jan 2018

Exploring The Relationship Between Group Cohesion And Compassion In Varsity Athletes, Theo Chu

Theses and Dissertations (Comprehensive)

Compassion is a prosocial behaviour characterized by kindness and a non-judgmental attitude to reduce one’s suffering. Typically, it is thought of as a behaviour we express outwardly to others, but compassion can also be directed internally toward ourselves. This is known as self-compassion. The benefits of having compassion for other people have been largely studied in employment settings and everyday life behaviours. Moreover, research has shown self-compassion is also related to many positive outcomes. Compared to compassion for others, self-compassion has been studied in sport, however it is still in its infancy. Although research has demonstrated the importance of both …

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Differences In Perceptions Of Aperture Crossing During A Virtual Reality Choice Reaction Task Between Non-Athletes And Varsity Athletes, Jaime Mitchell Jan 2018

Differences In Perceptions Of Aperture Crossing During A Virtual Reality Choice Reaction Task Between Non-Athletes And Varsity Athletes, Jaime Mitchell

Theses and Dissertations (Comprehensive)

Background: Vision will guide the actions and behaviors that allow us to circumvent environmental obstacles. When passing through a gap, individuals will consistently elicit a shoulder rotation (SR) if the gap is 1.4 times their shoulder width (SW) or narrower, with this behaviour being produced under various environmental conditions. Although a few studies have investigated perceptual predictions regarding gap passage, the effect of physical activity and the differences between trained and untrained athlete’s behaviours has not been examined. This study investigated the perceptual judgements of non-athletes and varsity athletes regarding the action they would utilize to pass through a dynamically …

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Bioinformatic Interrogation Of Phosphonate Tailoring Pathways, Monica Papinski Jan 2018

Bioinformatic Interrogation Of Phosphonate Tailoring Pathways, Monica Papinski

Theses and Dissertations (Comprehensive)

Phosphonates represent an underexploited class of natural products despite their tremendous potential for use in medicine and agriculture. Even less characterized are phosphonate-containing macromolecules such as cell wall lipids and glycans, distinguished by a P-C bond known to provide stability towards hydrolysis. Despite some progress made in revealing cell wall phosphonate tailoring (Pnt) pathways, several barriers impede the discovery and characterization of novel phosphonate biosynthetic pathways. Specifically, a large diversity of gene composition and arrangement is evident surrounding key genes established to participate in phosphonate tailoring pathways, which are identified alongside the presence of the ppm gene encoding the P-C …

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Initial Functional Characterization Of Bfo 2291 And Bfo 2294 From Tannerella Forsythia; Degraders Of Chondroitin Sulfate A, Rony Eshaque, Rony Eshaque Jan 2018

Initial Functional Characterization Of Bfo 2291 And Bfo 2294 From Tannerella Forsythia; Degraders Of Chondroitin Sulfate A, Rony Eshaque, Rony Eshaque

Theses and Dissertations (Comprehensive)

Periodontitis is characterized by the inflammation of the periodontal tissues in response to bacterial action. The Global Burden of Disease (GBD) 2010 study shows that periodontitis ranks 6thin the global prevalence of oral health conditions and affects 11% of the world population. It is initiated by the formation of biofilms containing different types of bacteria. These biofilms exist as dental plaque and contain three types of bacteria called Tannerella forsythia, Porphyromonasgingivalis, and Treponema denticola. These three types of bacteria are strongly associated with periodontitis and they are termed as the Red complex. The main focus of the …

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A Comparison Of The Stability & Pressure Distribution Between Young Adults And A Transtibial Amputee During Obstacle Crossing, Colin Kirst Jan 2018

A Comparison Of The Stability & Pressure Distribution Between Young Adults And A Transtibial Amputee During Obstacle Crossing, Colin Kirst

Theses and Dissertations (Comprehensive)

Falls are identified as the largest risk and leading cause of injury for multiple populations, including young adults and individuals with a transtibial amputation. Furthermore, obstacle crossing is identified as the number one cause of a trip, which subsequently leads to falling. Previous research provides conflicting results and a lack of specificity in certain outcome measures of dynamic stability during obstacle crossing. Therefore, the purpose of this thesis was to gain foundational knowledge on outcome measures related to dynamic stability during an obstacle crossing protocol. An additional purpose was to investigate the dynamic stability of young adults, and speculate on …

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Charecterization Of The Innate Immune Response In The Rat Intervertebral Disc At The Tissue And Cellular Level, Matthew Guerreiro Jan 2018

Charecterization Of The Innate Immune Response In The Rat Intervertebral Disc At The Tissue And Cellular Level, Matthew Guerreiro

Theses and Dissertations (Comprehensive)

Low back pain (LBP) affects up to 80% of the global population at some point during their life. The costs associated with LBP are estimated at $100 billion per year, putting significant strains on our healthcare system. As intervertebral disc (IVD) herniation is one of the major causes of LBP we decided to focus on herniation facilitated inflammatory responses, where damage caused by herniation triggers an innate immune response which likely results in pain, inflammation, and recruitment of specialized innate immune cells like macrophages to the affected area. Since the role of the inflammatory response is relatively uncharacterized in the …

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Examining The Effects Of Interleukin-6 On Appetite Regulatory Peptides In Lean And Obese Sedentary Males, Greg L. Mckie Jan 2018

Examining The Effects Of Interleukin-6 On Appetite Regulatory Peptides In Lean And Obese Sedentary Males, Greg L. Mckie

Theses and Dissertations (Comprehensive)

Acute moderate-intensity exercise transiently suppresses appetite via fluctuations in the appetite-regulatory peptides acylated ghrelin (AG), peptide tyrosine-tyrosine3-36 (PYY3-36), and active glucagon-like peptide-1 (GLP-1). Importantly, these effects do not lead to compensatory changes in energy intake in normal weight or obese individuals, highlighting the potential for exercise to induce acute energy deficits. One potential mechanism for these effects is increased post-exercise plasma concentrations of interleukin (IL)-6, as IL-6 has demonstrated appetite-inhibitory effects in animal and cell culture models. Given obesity is characterized by a state of chronic low-grade inflammation and associated with upregulated IL-6, this study sought to …

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The Influence Of Water Quality On Wetland-Associated Microbial Communities, Lindsey Clairmont Jan 2018

The Influence Of Water Quality On Wetland-Associated Microbial Communities, Lindsey Clairmont

Theses and Dissertations (Comprehensive)

Within a wetland environment, bacteria in association with plant roots play a vital role in maintaining the health of freshwater ecosystems. In order to gain insight into the stability and processes occurring within natural and constructed wetland environments we need to develop a better understanding of the relationship between wetland plants, root-associated microbial communities and environmental factors. Human population growth and urbanization have resulted in greater contaminant loads (inorganic nutrients, fecal contamination etc.) entering our waterways. As such, we need a better understanding of how anthropogenic impacts influence the structure and function of the wetland-associated microbial communities that we rely …

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Sprint Interval Training: Assessing Effectiveness And Adherence In A Real-World Setting, Gregory Howe Jan 2018

Sprint Interval Training: Assessing Effectiveness And Adherence In A Real-World Setting, Gregory Howe

Theses and Dissertations (Comprehensive)

Introduction: Perceived lack of time is an oft-cited reason for not engaging in physical activity. One proposed solution is high-intensity interval training (HIIT), or a more intense version known as sprint interval training (SIT), which involves repeated “all-out” efforts interspersed with short recovery periods. Although convincing evidence demonstrates the efficacy of SIT on cardiorespiratory fitness and other health factors, whether individuals will independently perform and benefit from this type of exercise outside the supervised lab setting is unknown. Purpose: To compare the effectiveness and adherence of performing running SIT and moderate-intensity continuous training (MICT) protocols in a real-world setting. Methods: …

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The Fatigue-Associated Changes In Estimates Of Persistent Inward Current In Human Motor Neurons, Chris Compton Jan 2018

The Fatigue-Associated Changes In Estimates Of Persistent Inward Current In Human Motor Neurons, Chris Compton

Theses and Dissertations (Comprehensive)

Neuromuscular fatigue is associated with reduced supraspinal drive. Similarly, intracortical facilitation and muscle activation are reduced following concussion. Both fatigue and mild traumatic brain injury are associated with increased noradrenergic and serotonergic activity in animal models. Given that monoaminergic-dependent persistent inward currents (PIC) set spinal motor neuron (MN) gain, we speculate that PIC will increase during fatigue to compensate for supraspinal hypoexcitability and that this will be more pronounced in people with concussion. Therefore, the purpose of this experiment was to assess spinal MN excitability during fatigue in people with concussion and healthy controls. 20 participants (10 concussion, average age …

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Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga Jan 2018

Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga

Theses and Dissertations (Comprehensive)

Lamprey (Petromyzontiformes) are a phylogenetically ancient group of jawless fishes that begin their lives as filter-feeding larvae (ammocoetes) before undergoing a complex metamorphosis into juvenile lamprey that involves major changes to their internal and external body plan. Some parasitic species, such as the sea lamprey (Petromyzon marinus), migrate to sea following metamorphosis, where they use their oral discs and rasping tongue to attach to and ingest vast quantities of blood from fishes. Thus, sea lamprey have to counter the simultaneous challenges of hyposmoregulation in sea water and the generation of large quantities of ammonia due to the …

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An Assessment Of The Plant And Mycorrhizal Community At Steeves Lake Shoreline, Colomac Mine, Nwt, Rebekah Hamp, Dr. Kevin Stevens Jan 2018

An Assessment Of The Plant And Mycorrhizal Community At Steeves Lake Shoreline, Colomac Mine, Nwt, Rebekah Hamp, Dr. Kevin Stevens

Theses and Dissertations (Comprehensive)

This study focused on the environmental impacts of mining and potential techniques to mitigate them. The goals of this study were to (1) Quantify vegetation and fungal colonization at a remediated mine site in northern Canada, and to determine if there were effects from petroleum hydrocarbon contamination, (2) Determine the response of northern plants inoculated with mycorrhizal fungi to diesel contamination. Mycorrhizal colonization was observed in field collected roots and trends in colonization and vegetation cover suggested that these communities were no longer impacted by residual contamination. Mean hyphal colonization of Elymus trachycaulus roots collected over two years was 47.3±3.8% …

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Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul Jan 2018

Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul

Theses and Dissertations (Comprehensive)

Accelerated climate warming in northern regions is causing permafrost degradation, leading to the reduction of the areal extent of permafrost. Permafrost is the foundation for many northern ecosystems and communities, so its thaw can have important ecological and societal consequences. Thaw of ice-rich permafrost can cause subsidence of the ground surface proportional to excess ice content. Terrain settlement can cause ponding or damage to infrastructure. Following a surface disturbance that removes much of the vegetation cover, a shift in the ground thermal regime can cause an increase in active layer thickness and rapid thaw of the top portion of permafrost. …

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Exploring Lactate’S Role In Appetite Regulation Following High-Intensity Exercise, Luke W. Vanderheyden Jan 2018

Exploring Lactate’S Role In Appetite Regulation Following High-Intensity Exercise, Luke W. Vanderheyden

Theses and Dissertations (Comprehensive)

Background: Intense-exercise has demonstrated an appetite suppressing effect post-exercise, however the involved mechanisms are not well understood. Lactate appears to be one viable mechanism as it has been found to bind to receptors on acylated ghrelin to inhibit release in cell culture. As sodium bicarbonate (NaHCO3) can alter lactate accumulation post-exercise without manipulating exercise-intensity, it presents an intriguing means to investigate lactate’s potential role. Purpose: To examine the role of lactate on appetite using NaHCO3 to alter blood lactate concentrations during high-intensity exercise. Methods: Eight recreationally active males completed two identical exercise sessions of low-volume high-intensity interval …

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A Qualitative Study Of Families’ Experiences With Food Insecurity In Addis Ababa, Ethiopia, Elias Omer Jan 2018

A Qualitative Study Of Families’ Experiences With Food Insecurity In Addis Ababa, Ethiopia, Elias Omer

Theses and Dissertations (Comprehensive)

Ethiopia has shown considerable progress in alleviating the decades-long food insecurity problem, but still, in the context of urban areas such as Addis Ababa families continue to struggle to make ends meet. The overall purpose of this research is to explore families’ lived experiences and coping mechanisms with food insecurity. Framed with the narrative-empowerment theoretical framework this ethnographic study outlines the findings of semi-structured interviews and focus group discussion of 35 adults and children and observational notes. Participants were able to tell their perception, causes, and impacts of food insecurity in their families. They outlined the daily strategies they employ …

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Seed Morphology, Dormancy And Germination Of South-West Australian Ericaceae, Michael Just Jan 2018

Seed Morphology, Dormancy And Germination Of South-West Australian Ericaceae, Michael Just

Theses: Doctorates and Masters

The Ericaceae in South West Australia contains species with difficult to germinate seeds, including many species with deep intractable dormancy. A better understanding of seed biology and species specific dormancy, and germination mechanisms is required to overcome these difficulties. Land clearing, salinity and disease has resulted in over 125 species within 15 genera being listed as rare, highly restricted, threatened and endangered (Western Australian Herbarium 1998–). The present study examined the seed biology of eight species of Ericaceae native to Western Australia, exploring fruit and seed morphology, dormancy and germination. Cold and warm stratification was used in combination with gibberellic …

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The Distribution And Trophic Ecology Of Golden Ghost Crabs (Ocypode Convexa), Caitlin Rae Jan 2018

The Distribution And Trophic Ecology Of Golden Ghost Crabs (Ocypode Convexa), Caitlin Rae

Theses: Doctorates and Masters

Sandy beaches make up approximately three-quarters of the world’s shorelines. They are important ecosystems, hosting abundant invertebrate macrofaunal communities that provide food resource for vertebrate predators such as shorebirds, seabirds, marine mammals and fish. Although possessing a terrestrial appearance, food input on sandy beaches is derived predominantly from the sea. Such food input includes detrital matter, mostly in the form of wrack, and has the potential to support a great diversity of species, as well as stabilising energy fluxes and dynamics of consumer populations. The movement of detritus, along with other vectors such as organisms and nutrients, across ecosystem boundaries …

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Within-Fire Patchiness Associated With Prescribed Burning In The Northern Jarrah Forests Of Western Australia, Zigourney Nielsen Jan 2018

Within-Fire Patchiness Associated With Prescribed Burning In The Northern Jarrah Forests Of Western Australia, Zigourney Nielsen

Theses: Doctorates and Masters

There is growing understanding of the importance of landscape mosaics and heterogeneity for biodiversity outcomes in Western Australia. However, there is limited information on the patchiness (spatial configuration of unburnt and burnt patches which occur at a range of spatial scales) within the perimeter of a single prescribed burn. Of particular concern is the idea that prescribed burning operations, carried out under very restricted weather and environmental conditions, can lead to structural and floristic homogenization of the area within a burn perimeter. This may be evident as reduced post-fire vegetation patchiness. Western Australian Jarrah (Eucalyptus marginata) forests are managed to …

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The Value Of Animal Behaviour As A Bio-Indicator Of Restoration Quality, Floyd Holmes Jan 2018

The Value Of Animal Behaviour As A Bio-Indicator Of Restoration Quality, Floyd Holmes

Theses: Doctorates and Masters

Woodland restoration is a complex endeavour, and restoration ecology as a scientific discipline requires constant re-assessments and adjustments if it is to improve outcomes and better provide for biodiversity. The promise of effective restoration is often used to justify destructive processes that affect many of the world’s ecosystems. It is therefore imperative that those promises can be met, which comes down to restoration ecologists’ and land managers’ capacity to predict and facilitate desirable ecological changes in a timely and socio-economically responsible manner. As perspectives have changed, and knowledge has been gained over the past few decades there have been several …

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Antibiotic Resistance In Gram Negative Bacteria Isolated From Fish Sold In Western Australia, Hannah Kathleen Robinson Jan 2018

Antibiotic Resistance In Gram Negative Bacteria Isolated From Fish Sold In Western Australia, Hannah Kathleen Robinson

Theses: Doctorates and Masters

Background Information The global misuse and overuse of antibiotics in human medicine and the animal production industry is contributing to the development of antibiotic resistance in bacteria. This is a serious threat to modern medicine and public health. Antibiotic resistant organisms can cause severe infections in humans which are difficult to treat, and in some cases impossible to resolve which can lead to premature death. Several studies have been conducted across the globe to assess the use of antibiotics in the seafood industry and the associated health risks, however, limited studies have recently explored this risk in an Australian setting. …

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Behavioral Patterns Of Blinded Vs. Mock-Blinded Male Individuals In The Presence Of Females: Analysis Of The Role Of Eyes In Euphilomedes Carcharodonta Mating, Alexis Arenz Jan 2018

Behavioral Patterns Of Blinded Vs. Mock-Blinded Male Individuals In The Presence Of Females: Analysis Of The Role Of Eyes In Euphilomedes Carcharodonta Mating, Alexis Arenz

University of the Pacific Theses and Dissertations

Sexual dimorphism is exhibited throughout various organisms and takes an extensive variety of forms, although rarely does it take the form of eye-reduction within a population. This poses the question of whether this dimorphism arises due to sexual selection in order to increase reproductive success or rather from ecological selection as a result of sex-specific niche partitioning. In this case, we study an organism that displays a drastic form of sexual dimorphism, in that the males have large complex lateral eyes whereas the females lack eyes and merely have rudimentary lateral eye-spots. Euphilomedes carcharodonta is a small crustacean native to …

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Evidence That A Partner-Switching Regulatory System Modulates Hormogonium Motility In The Filamentous Cyanobacterium Nostoc Punctiforme, Kelsey Wynne Riley Jan 2018

Evidence That A Partner-Switching Regulatory System Modulates Hormogonium Motility In The Filamentous Cyanobacterium Nostoc Punctiforme, Kelsey Wynne Riley

University of the Pacific Theses and Dissertations

Partner-switching regulatory systems (PSRSs) are utilized by many different bacteria to regulate a wide array of cellular responses, from stress response to expression of virulence factors. The filamentous cyanobacterium Nostoc punctiforme can transiently differentiate motile filaments, called hormogonia, in response to various changes in the environment. Hormogonia utilize a Type IV pilus (T4P) complex in conjunction with a secreted polysaccharide for gliding motility along solid surfaces. This study identified three genes, designated hmpU, hmpW, and hmpV, encoding the protein components of a PSRS involved in regulation of hormogonium motility in N. punctiforme. Although mutant strains with in-frame deletions in hmpU, …

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Should I Stay Or Should I Go? Complex Environments Drive The Developmental Plasticity Of Flight Capacity And Flight-Related Tradeoffs, Jordan R. Glass Jan 2018

Should I Stay Or Should I Go? Complex Environments Drive The Developmental Plasticity Of Flight Capacity And Flight-Related Tradeoffs, Jordan R. Glass

University of the Pacific Theses and Dissertations

Animals must balance multiple, fitness-related traits in environments that are complex and characterized by co-varying factors, such as co-variation in temperature and food availability. Thus, experiments manipulating multiple environmental factors provide valuable insight into the role of the environment in shaping not only important traits (e.g., dispersal capacity or reproduction), but also trait-trait interactions (e.g., trade-offs between traits). We employed a multi-factorial design to manipulate variation in temperature (constant 28°C vs. 28±5°C daily cycle) and food availability (unlimited vs. intermittent access) throughout development in the sand field cricket, Gryllus firmus. We found that fitness-related, life-history traits and trait trade-offs can …

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Dna Lesions Produced From The Reaction Of Diols And 5-Formylcytosine And Their Effects On Dna Replication, Brock Allen Jan 2018

Dna Lesions Produced From The Reaction Of Diols And 5-Formylcytosine And Their Effects On Dna Replication, Brock Allen

University of the Pacific Theses and Dissertations

Nucleic acids are complex macromolecules that are susceptible to both endogenous and exogenous damage. This study explored damage resulting from interactions with environmental nucleophilic toxins, such as a variety of diols and amines found in industry. These nucleophiles can react with electrophilic groups, such as 5-formylcytosine. 5-formylcytosine is an oxidation product of the epigenetic base 5-methylcytosine. It is typically removed by thymine DNA glycosylase (TDG) but is known to accumulate in the genome, making the formyl group susceptible to attack. In this study we used GC/MS and ESI-MS to show that DNA lesions from the nucleophilic addition reaction of toxins …

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