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Biology 122 Anatomy And Physiology Ii Summer 2015, Tammy Knox Jan 2015

Biology 122 Anatomy And Physiology Ii Summer 2015, Tammy Knox

Biology Courses

No abstract provided.

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Reintroduction Biology Of Head-Started Ornate Box Turtles, Eric R. Sievers Jan 2015

Reintroduction Biology Of Head-Started Ornate Box Turtles, Eric R. Sievers

Graduate Theses/Dissertations

The ornate box turtle (Terrapene ornata) is a prairie-dwelling species that has experienced population declines, especially near the northern edge of its range. In order to provide supporting research for a reintroduction program at the Upper Mississippi River National Wildlife and Fish Refuge in northwestern Illinois, I compared the relative success of different approaches to reintroduction. Specifically, I tested the null hypothesis that reintroduced turtles exhibited equal reintroduction success when, 1) released at a site that is known to support a viable ornate box turtle population, 2) ‘soft-released' in a fenced enclosure at a site where very few ornate box …

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A Multifaceted Trophic Cascade In A Detritus-Based System: Density-, Trait-, Or Processing-Chain-Mediated Effects, Daniel Albeny-Simões, Ebony G. Murrell, Evaldo F. Vilela, Steven A. Juliano Jan 2015

A Multifaceted Trophic Cascade In A Detritus-Based System: Density-, Trait-, Or Processing-Chain-Mediated Effects, Daniel Albeny-Simões, Ebony G. Murrell, Evaldo F. Vilela, Steven A. Juliano

Faculty Publications – Biological Sciences

We investigated three pathways by which predators on an intermediate trophic level may produce a trophic cascade in detritus-based systems. Predators may increase lower trophic levels (bacteria) by reducing density of bacteriovores, by altering behavior of bacteriovores, and by processing living bacteriovores into carcasses, feces, and dissolved nutrients that are substrates for bacteria. We tested these pathways in laboratory experiments with mosquitoes in water-filled containers. Larval Toxorhynchites rutilus prey on larval Aedes triseriatus, which feed on bacteria. Using containers stocked with oak leaf infusion as a bacterial substrate, we compared bacterial productivity at 7 and 14 days for: prey …

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The Effects Of Substrate Roughness In Air And Water On The Gecko Adhesive System, Amanda Palecek Jan 2015

The Effects Of Substrate Roughness In Air And Water On The Gecko Adhesive System, Amanda Palecek

Williams Honors College, Honors Research Projects

In an effort to better understand the fascinating gecko adhesive system, scientists have long tested the abilities of the gecko in controlled conditions that mimic the gecko’s native environment. The effects of humidity, environmental temperature, and exposure to water have all been tested. Roughness, however has not been studied in great detail. Surfaces of varying roughnesses are all over the gecko’s natural environment. We tested geckos on hydrophilic silicon carbide sandpapers of varying roughnesses in both air and water to attempt to better study the effects of roughness on gecko adhesion. When tested on the rougher (1 µm) surface, the …

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Effects Of The Exotic Red Imported Fire Ant (Solenopsis Invicta) On The Growth And Survival Of The Threatened Hooded Pitcher Plant (Sarracenia Minor), Edward Marques Jan 2015

Effects Of The Exotic Red Imported Fire Ant (Solenopsis Invicta) On The Growth And Survival Of The Threatened Hooded Pitcher Plant (Sarracenia Minor), Edward Marques

UNF Graduate Theses and Dissertations

Plants and insects are some of the most biodiverse groups in the world and are constantly interacting. One unique interaction that has been observed occurs between carnivorous plants and insects; some plant species are capable of capturing and digesting insects for nutrients. Despite preying on these insects, there are cases where such interactions can been viewed as mutualistic. For instance, a nectar reward is produced by the plant to attract insects, and during visitation insects may fall prey to these plants. Additionally, carnivorous myrmecophytic plants may receive an added indirect benefit in the form of reduced herbivory, since ants have …

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Behavioral Response Of Pacific Lamprey (Entosphenus Tridentatus) To Predator Odors, Laurie L. Porter Jan 2015

Behavioral Response Of Pacific Lamprey (Entosphenus Tridentatus) To Predator Odors, Laurie L. Porter

All Master's Theses

Pacific lamprey (Entosphenus tridentatus), a species facing serious threats to their existence, experience a number of challenges in reaching their desired spawning grounds during the adult migratory phase, and predators are suspected to be one of these challenges. Understanding if Pacific lamprey respond to predator odorants may provide a management tool for use in conjunction with attractants in guiding lamprey to suitable spawning habitat and deterring them from poor habitat. Previous research has failed to explore Pacific lamprey response to predator odorants, although much research exists on attractant odorants. In our study, we tested Pacific lamprey response to …

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Feasibility Of Incorporating Electrogastrography Into An Undergraduate Physiology Laboratory Curriculum, Lauren A. Foropoulos Jan 2015

Feasibility Of Incorporating Electrogastrography Into An Undergraduate Physiology Laboratory Curriculum, Lauren A. Foropoulos

Honors Theses

This study aimed to detect the effects of mental stress on gastric motility in college students through the use of cutaneous electrogastrography (EGG). Additionally, the study aimed to determine the feasibility of creating a laboratory curriculum for a cutaneous electrogastrography experiment that an undergraduate could perform, analyze, and interpret during a three hour physiology lab. Through this study and the laboratory procedures designed from the experiment, undergraduates will be able to interpret the physiological aspects of gastrointestinal function within the human body, including how it is effected by mental stress. According to previous studies by Yin et al. (2004) and …

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An Examination Of Microbial Populations In Different Brands And Flavors Of Ice Cream, Madeline Campbell Jan 2015

An Examination Of Microbial Populations In Different Brands And Flavors Of Ice Cream, Madeline Campbell

Honors Theses

Outbreaks of foodborne illness are of concern to many Americans. While pasteurization of ingredients and freezing eliminates most microbiological hazards, ice cream can act as a vehicle for pathogen transmission and be a cause of foodborne disease. This study examined the bacterial content of seven nationally distributed brands of ice cream and one local farmer's market brand. The aims of the study were to (1) determine if there was a higher bacterial content in chocolate and strawberry ice cream compared to vanilla ice cream, potentially because of more ingredients and more opportunities for bacterial contamination in those flavors, and (2) …

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Muscle Fatigue Resistance Via Energy Drink Consumption — Assessment Of Pre- And Post- Experiment Participant Feedback, Mary Kathleen Robbins Jan 2015

Muscle Fatigue Resistance Via Energy Drink Consumption — Assessment Of Pre- And Post- Experiment Participant Feedback, Mary Kathleen Robbins

Honors Theses

Energy drink consumption poses a health risk among college students, and long-term health implications are unclear. Because energy drinks are classified as dietary supplements, the FDA is not responsible for proving consumption is safe for the consumer. This research project studies the consumption of an energy drink and an energy bean's effect on muscle fatigue using a grip force transducer, subjective perceptions of the participants after consumption across the two trials, and subjects' opinion of energy drinks after the conclusion of the experiment. All subjects, ages 18-24 and regular users of caffeine, were recruited through email at the University of …

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Does This Have Gluten? Comparison Of Gluten-Free And Unrestricted Diets In Intestinal Bacterial Populations And Diversity, Bradshaw Hammond Jan 2015

Does This Have Gluten? Comparison Of Gluten-Free And Unrestricted Diets In Intestinal Bacterial Populations And Diversity, Bradshaw Hammond

Honors Theses

As different diets continue to grow in popularity within the United States, the effect of these diets upon bacteria in the intestines is only beginning to be understood. This study focused on the effect that a shift to a gluten-free diet has on the human gut microbiome. Three genetically close subjects were selected for observation over a six month time period. One subject observed a consistent gluten-free diet. A second subject started on an unrestrictive diet, switched to a gluten-free diet for three months, then returned to an unrestricted diet for an additional three months. The third subject left an …

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Identification And Pathogenicity Of Bacteria In The Mediterranean Corn Borer Sesamia Nonagrioides Lefebvre (Lepidoptera: Noctuidae), Ardahan Eski̇, Fi̇li̇z Özkan Çakici, Mustafa Güllü, Hacer Muratoğlu, Zi̇hni̇ Demi̇rbağ, İsmai̇l Demi̇r Jan 2015

Identification And Pathogenicity Of Bacteria In The Mediterranean Corn Borer Sesamia Nonagrioides Lefebvre (Lepidoptera: Noctuidae), Ardahan Eski̇, Fi̇li̇z Özkan Çakici, Mustafa Güllü, Hacer Muratoğlu, Zi̇hni̇ Demi̇rbağ, İsmai̇l Demi̇r

Turkish Journal of Biology

Sesamia nonagrioides (Lep.: Noctuidae) is one of the most serious pests of corn in Turkey and other Mediterranean countries. Although various cultural, chemical, and biological methods are used to control this pest, its damage still continues in all Mediterranean countries. In this study, to find an effective bacterium that can be used as a biocontrol agent against S. nonagrioides, we isolated 15 bacteria from S. nonagrioides larvae and evaluated the larvicidal potency of all isolates on the pest. According to their morphological, physiological, biochemical, and molecular properties, the isolates were identified as Achromobacter insolitus (Sn1), Morganella morganii (Sn2), Klebsiella pneumoniae …

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Antioxidant Activity Of Heme Oxygenase 1 In Brassica Juncea (L.) Czern.(Indian Mustard) Under Salt Stress, Khushbu Verma, Shubham Dixit, Gyan Singh Shekhawat, Afroz Alam Jan 2015

Antioxidant Activity Of Heme Oxygenase 1 In Brassica Juncea (L.) Czern.(Indian Mustard) Under Salt Stress, Khushbu Verma, Shubham Dixit, Gyan Singh Shekhawat, Afroz Alam

Turkish Journal of Biology

Antioxidant enzymes play a protective role in plants under oxidative stress. The present study explores the role of antioxidant system heme oxygenase1 (HO1) in Brassica juncea (L.) Czern. in salt stress conditions. B. juncea seedlings were treated with different NaCl concentrations (0-200 mM) for 5 days. Salt stress elicited the highest response at 150 mM NaCl concentration; at this level, gene expression of HO1 was also upregulated. Apart from HO1, ascorbate peroxidase (APX), peroxidase (POD), and glutathione reductase (GR) also showed their highest activity at 150 mM NaCl concentration. The study shows that HO1 is indispensable in B. juncea for …

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Designing A Bacterial Biosensor For Detection Of Mercury In Water Solutions, Amir Roointan, Nooshin Shabab, Jamshid Karimi, Alireza Rahmani, Mohammad Yousef Alikhani, Massoud Saidijam Jan 2015

Designing A Bacterial Biosensor For Detection Of Mercury In Water Solutions, Amir Roointan, Nooshin Shabab, Jamshid Karimi, Alireza Rahmani, Mohammad Yousef Alikhani, Massoud Saidijam

Turkish Journal of Biology

Due to increasing advances in physical and chemical techniques for the assessment of pollutants in the environment, there is an immediate demand for a bioassay that can report both the presence of an analyte and its biological effects. In accordance with this need, there has been a fast growth in whole-cell biosensor technology. In this study we aimed to design a whole-cell bacterial biosensor to detect mercury in liquid solutions. The Pseudomonas pBS228 merR gene and its related promoter/operator was synthesized by Bioneer. The green fluorescence protein (GFP) gene was used as a reporter. GFP was cloned downstream of the …

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Storage Temperature Of Boar Semen And Its Relationship To Changes In Sperm Plasma Membrane Integrity, Mitochondrial Membrane Potential, And Oxidoreductive Capability, Dariusz Gaczarzewicz, Jan Udala, Malgorzata Piasecka, Barbara Blaszczyk, Tomasz Stankiewicz Jan 2015

Storage Temperature Of Boar Semen And Its Relationship To Changes In Sperm Plasma Membrane Integrity, Mitochondrial Membrane Potential, And Oxidoreductive Capability, Dariusz Gaczarzewicz, Jan Udala, Malgorzata Piasecka, Barbara Blaszczyk, Tomasz Stankiewicz

Turkish Journal of Biology

The aim of this study was to analyze changes in sperm plasma membrane integrity, mitochondrial activity, and extracellular environment during storage of boar semen at 5 °C, 16 °C, and 25 °C for 10 days. Progressive sperm motility, plasma membrane integrity (SYBR-14/PI-test and HOS test), aspartate aminotransferase (AAT), and mitochondrial activity (JC-1-test and NADH-dependent NBT assay), as well as pH and osmolality were assessed in nine ejaculates of Polish Landrace boars. The plasma membrane integrity of the semen stored at 5 °C was similar to that of the semen stored at 16 °C and 25 °C; however, an increase in …

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Melatonin, Mitochondria, And Ca2+ Homeostasis In The Exocrine Pancreas: An Overview, Antonio Gonzalez, Patricia Santofimia-Castaño, Gines Maria Salido Jan 2015

Melatonin, Mitochondria, And Ca2+ Homeostasis In The Exocrine Pancreas: An Overview, Antonio Gonzalez, Patricia Santofimia-Castaño, Gines Maria Salido

Turkish Journal of Biology

Melatonin, a derivative of the amino acid tryptophan, was initially thought to be mainly produced and secreted by the pineal gland; with time, it was also found in other tissues and organs, and even in plants. Since its discovery, the study of the role of the indole in cellular homeostasis has generated impressive data, which have led researchers to a common idea regarding the positive actions of melatonin in health. The uncontrolled production of free radicals in cellular systems leads to the situation termed oxidative stress, which has been signaled as the basis of disease and aging. In the exocrine …

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Melatonin Is A Potent Modulator Of Antioxidative Defense And Cellular Proliferation Against Aluminum Toxicity In Rats, Ni̇hal Ömür Bulan, Guner Sarikaya-Unal, Sevim Tunali, Pelin Arda Pi̇ri̇nççi̇, Refiye Yanardag Jan 2015

Melatonin Is A Potent Modulator Of Antioxidative Defense And Cellular Proliferation Against Aluminum Toxicity In Rats, Ni̇hal Ömür Bulan, Guner Sarikaya-Unal, Sevim Tunali, Pelin Arda Pi̇ri̇nççi̇, Refiye Yanardag

Turkish Journal of Biology

Aluminum is the most abundant metal on earth, known for its toxicity to humans and laboratory animals. Melatonin, produced by the pineal gland, has been shown to be an effective antioxidant. In this study, we investigated the possible protective role of melatonin in modulating toxicity and oxidative stress induced by chronic exposure to aluminum in the small intestine of rats. Wistar albino rats were divided into five groups. Group I served as the control and received only physiological saline, Group II served as the control for the melatonin group and received ethanol and physiological saline, Group III received melatonin, Group …

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Effects Of Photoperiod Variations And Alpha-Lipoic Acid Treatment On Melatonin,Cortisol, And Oxidative Stress Levels In The Blood Of Rats, Cahi̇de Çevi̇k, Recep Aslan Jan 2015

Effects Of Photoperiod Variations And Alpha-Lipoic Acid Treatment On Melatonin,Cortisol, And Oxidative Stress Levels In The Blood Of Rats, Cahi̇de Çevi̇k, Recep Aslan

Turkish Journal of Biology

This study aimed to investigate the effects of frequently changing photoperiods and alpha-lipoic acid treatment on melatonin, cortisol, oxidative markers, and some blood parameters. Eighty-four rats were randomly and equally divided into 7 groups: a control group, 3 prolonged light groups, and 3 prolonged dark groups. The study was completed in 2 stages, with 1- and 4-week periods, respectively. Blood samples were obtained at the end of the first and fourth weeks, and at the end of the dark period for the first and second stages. Serum aspartate aminotransferase and creatinine levels were significantly elevated in the prolonged dark olive …

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Limitations Of Host Plant Use In Two Andean Altinote (Nymphalidae, Heliconiinea, Acraeini), Butterflies, From A Tritrophic Perspective, Karen M. Pedersen Jan 2015

Limitations Of Host Plant Use In Two Andean Altinote (Nymphalidae, Heliconiinea, Acraeini), Butterflies, From A Tritrophic Perspective, Karen M. Pedersen

Browse all Theses and Dissertations

Despite the clear advantages of generalist feeding, many insect herbivores feed on a relatively small number of available host plants with in phylogenetically restricted groups. To better understand patterns of host plant use I used the sister species Altinote stratonice and Altinote dicaeus and their overlapping but distinct host plant range. I measured physiological effects of plants by using development time, pupal mass, and survival. To determine the importance of enemies I quantified rates of parasitism and rates of predation. Finally I measured host plant frequency, and host plant abundance. I found that survival of A. dicaeus and A. stratonice …

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The Dietary Mineral Content Of Claytonia Lanceolata Corms From Multiple Populations Across The Columbia Plateau Region Of North America, Paul Reilly Jan 2015

The Dietary Mineral Content Of Claytonia Lanceolata Corms From Multiple Populations Across The Columbia Plateau Region Of North America, Paul Reilly

EWU Masters Thesis Collection

"Since divergence from our ancestral lineage ~ 2.8 mya, humans have relied on foraged foods to obtain dietary mineral nutrition. Around 12,000 years ago, people began shifting towards a lifestyle of food production. The rapid shift in lifestyle significantly altered the human diet, and research suggests our genomes have had insufficient time to adjust. Due to the discord between genome and environment, unprecedented levels of disease and malnutrition are epidemic in certain subsets of the population. Studies suggest the most cost effective way to mitigate the risk of these diseases is to find ways to increase micronutrient consumption. As a …

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Paper-Based Biosensor For Colorimetric Detection Of Psa Biomarker, Alyson Drew Jan 2015

Paper-Based Biosensor For Colorimetric Detection Of Psa Biomarker, Alyson Drew

Honors Theses

Prostate cancer is commonly screened in the bloodstream by detection of excess PSA, prostate-specific antigen which is a protein in the prostate produces in large quantities when cancerous tumors are present. In order to facilitate inexpensive and disposable detection, diagnostic tools have begun to be created out of paper and wax which wick solutions through channels based on their hydrophobicity. George M. Whitesides, who pioneered the majority of this work, designed a paper-based LFD, lateral flow device, effective for detecting liver function which we are modifying to detect PSA. In this paper, we designed an oPAD, origami paper analytical device, …

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Dual Functions For Insulinoma-Associated 1 In Retinal Development, Marie A. Forbes-Osborne Jan 2015

Dual Functions For Insulinoma-Associated 1 In Retinal Development, Marie A. Forbes-Osborne

Theses and Dissertations--Biology

Proper visual system function requires tightly controlled proliferation of a pool of relatively homogeneous retinal progenitor cells, followed by the stepwise specification and differentiation of multiple distinct cell types. These retinal cells, both neuronal and glial, must be generated in the correct numbers, and the correct laminar location to permit the formation of synaptic connections between individual cell types. After synapses are made, constant signaling is required as part of normal retinal function, and to maintain cellular identity and connectivity. These processes rely on both extrinsic and intrinsic signaling, with regulation of gene expression by cascades of transcription factors having …

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Functional Approach To Condition, Dustin J. Wilgers, Eileen A. Hebets Jan 2015

Functional Approach To Condition, Dustin J. Wilgers, Eileen A. Hebets

Eileen Hebets Publications

Animal signaling is commonly thought to be costly. Signaling costs can arise via a variety of avenues, including energy expenditure, predator attraction, and so on (reviews in Zuk and Kolluru, 1998; Kotiaho, 2001), and are predicted to increase with signal expression (e.g., size, amplitude, and intensity; Johnstone, 1997). Due to these costs, signaler condition, which is hypothesized to be a reflection of a signaler’s genetic quality, is expected to influence the level of signal expression one can afford (Zahavi, 1975), resulting in a positive correlation between signaler condition and signal expression – that is, condition-dependent signaling (Zahavi, 1977; West-Eberhard, 1979; …

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Evolution In Action: Climate Change, Biodiversity Dynamics And Emerging Infectious Disease, Eric P. Hoberg, Daniel R. Brooks Jan 2015

Evolution In Action: Climate Change, Biodiversity Dynamics And Emerging Infectious Disease, Eric P. Hoberg, Daniel R. Brooks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Climatological variation and ecological perturbation have been pervasive drivers of faunal assembly, structure and diversification for parasites and pathogens through recurrent events of geographical and host colonization at varying spatial and temporal scales of Earth history. Episodic shifts in climate and environmental settings, in conjunction with ecological mechanisms and host switching, are often critical determinants of parasite diversification, a view counter to more than a century of coevolutionary thinking about the nature of complex host–parasite assemblages. Parasites are resource specialists with restricted host ranges, yet shifts onto relatively unrelated hosts are common during phylogenetic diversification of parasite lineages and directly …

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Nutritional Physiology Of Life-History Trade-Offs: How Food Protein–Carbohydrate Content Influences Life-History Traits In The Wing-Polymorphic Cricket Gryllus Firmus, Rebecca M. Clark, Anthony J. Zera, Spencer T. Behmer Jan 2015

Nutritional Physiology Of Life-History Trade-Offs: How Food Protein–Carbohydrate Content Influences Life-History Traits In The Wing-Polymorphic Cricket Gryllus Firmus, Rebecca M. Clark, Anthony J. Zera, Spencer T. Behmer

School of Biological Sciences: Faculty Publications

Although life-history trade-offs result from the differential acquisition and allocation of nutritional resources to competing physiological functions, many aspects of this topic remain poorly understood. Wing-polymorphic insects, which possess alternative morphs that trade off allocation to flight capability versus early reproduction, provide a good model system for exploring this topic. In this study, we used the wing-polymorphic cricket Gryllus firmus to test how expression of the flight capability versus reproduction trade-off was modified across a heterogeneous protein–carbohydrate nutritional landscape. Newly molted adult female long- and short-winged crickets were given one of 13 diets with different concentrations and ratios of protein …

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A Coxiella-Like Endosymbiont Is A Potential Vitamin Source For The Lone Star Tick, Todd A. Smith, Timothy Driscoll, Joseph J. Gillespie, Rahul Raghavan Jan 2015

A Coxiella-Like Endosymbiont Is A Potential Vitamin Source For The Lone Star Tick, Todd A. Smith, Timothy Driscoll, Joseph J. Gillespie, Rahul Raghavan

Biology Faculty Publications and Presentations

Amblyomma americanum (Lone star tick) is an important disease vector in the United States. It transmits several human pathogens, including the agents of human monocytic ehrlichiosis, tularemia, and southern tick-associated rash illness. Blood-feeding insects (Class Insecta) depend on bacterial endosymbionts to provide vitamins and cofactors that are scarce in blood. It is unclear how this deficiency is compensated in ticks (Class Arachnida) that feed exclusively on mammalian blood. A bacterium related to Coxiella burnetii, the agent of human Q fever, has been observed previously within cells of A. americanum. Eliminating this bacterium (CLEAA, Coxiella-like endosymbiont of A. americanum) with antibiotics …

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Sex Dependent Efficacy Of Taurine As A Treatment For Cocaine Drug Use: A Study Of Reward, Kevin Uribe Jan 2015

Sex Dependent Efficacy Of Taurine As A Treatment For Cocaine Drug Use: A Study Of Reward, Kevin Uribe

Dissertations and Theses

No abstract provided.

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Not Got Milk? The Effect On The Gut Microbiome Of Removing Dairy From The Diet, Patrick Tyler Stovall Jan 2015

Not Got Milk? The Effect On The Gut Microbiome Of Removing Dairy From The Diet, Patrick Tyler Stovall

Honors Theses

The human gut contains a highly diverse set of bacteria that perform a wide range of duties that include much more than just nutrient acquisition. However, the composition of this community is subject to change, with diet, age and lifestyle playing roles in the development and maintenance of the gut microbiota. This study compared the bacterial composition of the human gut when consuming a normal diet versus a dairy-free diet. Samples were taken from a single subject during three periods: 1) control (normal) diet, 2) dairy-free diet, and 3) a return to normal diet. Gut bacterial communities were identified and …

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Molecular Identification And Functional Characteristics Of Peptide Transporter 1 (Pept1) In The Bonnethead Shark (Sphyrna Tiburo), Hannah Hart Jan 2015

Molecular Identification And Functional Characteristics Of Peptide Transporter 1 (Pept1) In The Bonnethead Shark (Sphyrna Tiburo), Hannah Hart

UNF Graduate Theses and Dissertations

Many elasmobranchs are considered top predators with worldwide distribution, and in general these fish play an important role in the transfer of energy from the lower to the upper trophic levels within the marine ecosystem. Despite this, little research has been done regarding the rates of prey ingestion, digestion, and the processes of energy and nutrient absorption. Specifically understudied is enzymatic digestion within the intestinal brush border, which functions to break down macromolecules into smaller subunits for luminal absorption across the gastrointestinal epithelium. Given their carnivorous diet, the present study sought to expand knowledge on nutrient intake in elasmobranchs by …

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Expression And Functional Analysis Of Lipids And Glycolipids From The Mammal-Dwelling Stages Of Trypanosoma Cruzi, Felipe Gazos Lopes Jan 2015

Expression And Functional Analysis Of Lipids And Glycolipids From The Mammal-Dwelling Stages Of Trypanosoma Cruzi, Felipe Gazos Lopes

Open Access Theses & Dissertations

Trypanosoma cruzi is the causative agent of the life-threatening Chagas disease, in which increased platelet aggregation related to myocarditis is observed. Platelet-activating factor (PAF) is a potent intercellular lipid mediator and second messenger that exerts its activity through a PAF-specific receptor (PAFR). Previous data from our group suggested that T. cruzi synthesizes a phospholipid with PAF-like activity. The structure of T. cruzi PAF-like molecule, however, remains elusive. Here, we have purified and structurally characterized the putative T. cruzi PAF-like molecule by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). Our ESI-MS/MS data demonstrated that the T. cruzi PAF-like molecule is actually a lysophosphatidylcholine …

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The Evolutionary Biology Of Vision In Daphnia, Christopher S. Brandon Jan 2015

The Evolutionary Biology Of Vision In Daphnia, Christopher S. Brandon

Theses and Dissertations

Eyes have attracted the attention of evolutionary biologist since the field’s infancy. In On the Origin of Species, in fact, Darwin famously remarked on the proposition that natural selection could engineer the eye, saying “[it is] absurd in the highest possible degree.” Though, he goes on to explain, beautifully and simply, how his theory of evolution by natural selection could produce such an organ. Indeed, eyes are remarkable examples of complex information acquisition systems that have evolved from simple beginnings. Eyes allow animals to extract environmental information from light, which informs physiological and behavioral responses to resources, predation, and mates. …

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