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Using Mechanical Resonance To Overcome Van Der Waals Forces In Optical Trapping Experiments, Nathan B. Terry, Dr. Justin B. Peatross Feb 2014

Using Mechanical Resonance To Overcome Van Der Waals Forces In Optical Trapping Experiments, Nathan B. Terry, Dr. Justin B. Peatross

Journal of Undergraduate Research

The laser trapping of microscopic particles has many applications, especially in chemistry, biology and physics (1). It is of special interest to utilize optical trapping to levitate small objects for interferometry work. The levitation of a glass microsphere requires first that the Van der Waals forces between the sphere and the surface on which it rests (the contact surface) must be overcome. The first stage of this experiment examines overcoming these Van der Waal forces by mechanically vibrating the contact surface.

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The Flea Family Tree: Phylogeny Of The Order Siphonaptera Based On 18s Rdna, 28s Rdna, Elongation Factor-1alpha, And Cytochrome Oxidase Ii Gene Regions, Alison Swindle, Dr. Michael F. Whiting Feb 2014

The Flea Family Tree: Phylogeny Of The Order Siphonaptera Based On 18s Rdna, 28s Rdna, Elongation Factor-1alpha, And Cytochrome Oxidase Ii Gene Regions, Alison Swindle, Dr. Michael F. Whiting

Journal of Undergraduate Research

Fleas are laterally compressed, wingless insects with small helmet shaped heads, and mouthparts specialized for feeding on the blood of their hosts. These morphological specializations make it possible for fleas to be entirely ectoparasitic, but they also make it difficult to find distinguishing characters on which to base taxonomy above the generic level (Holland, 1964). The highly derived state of flea morphology has resulted in questionable classification within the order, and lack of solid support for any group as the sister taxon to fleas. To this point there has been no molecular study that has considered fleas below the ordinal …

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Isolation And Structural Elucidation Of Cancer Therapeutic Agents In Rhamnaecae Ziziphus Obtusifolia, Matthew Woll, Dr. Noel Owen Feb 2014

Isolation And Structural Elucidation Of Cancer Therapeutic Agents In Rhamnaecae Ziziphus Obtusifolia, Matthew Woll, Dr. Noel Owen

Journal of Undergraduate Research

Many important and useful biological compounds are found in plants. Extensive work has been done on evaluating anti-cancer 1, 2, anti-malarial 3, and anti-viral 4 properties of plants. The Yaqui Indians of northern Mexico have traditionally used many natural products to cure various diseases. Gloria Moroyoqui, the daughter of a Yaqui Indian shaman (medicine man) explained to us some of the plants and their uses as medicine. The Yaqui Indians have used Rhamnacae ziziphus obtusifolia, commonly known as graythorn, as a cancer chemotherapeutic agent.

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Bax Induced Apoptosis Under Control Of The Tk1 Promoter, Scott A. Witt, Dr. Kim L. O'Neill Feb 2014

Bax Induced Apoptosis Under Control Of The Tk1 Promoter, Scott A. Witt, Dr. Kim L. O'Neill

Journal of Undergraduate Research

The human body has an automatic system for eliminating unwanted cells. When it is time for a cell to be removed, it is given a signal to divide up its parts into discrete packages and send them to other cells to be recycled. The cell eventually disintegrates. This process is called apoptosis, or programmed cell death. Every cell in the body has the mechanism, but only the ones receiving the signal will die. Sometimes, certain cells lose the ability to undergo programmed cell death. The result is a group of unwanted cells that refuse to die properly-cancer.

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Conservation Of The Che And Pho Systems In Escherichia Coli, Kimberly B. Zumbrennen, Dr. William R. Mccleary Feb 2014

Conservation Of The Che And Pho Systems In Escherichia Coli, Kimberly B. Zumbrennen, Dr. William R. Mccleary

Journal of Undergraduate Research

Bacteria live in a continuously changing environment. In order to survive, bacteria must monitor nutrients, acidity, temperature, osmolarity, etc. The use of two-component systems to sense and respond to these environmental changes is a common motif observed in a wide variety of organisms. A two-component system consists of two main proteins, a sensor and a response regulator(2). The sensor protein is a trans-membrane protein which monitors environmental fluctuations and activates the response regulator through phosphorylation. The response regulator contains two domains, the receiver module and the output domain. The receiver module is phosphorylated and dephosphorylated by the sensor protein. Communication …

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Determining The Mechanism Of How The 2,4-Dichlorophenoxyacetic Acid Pathway Of Plasmid Pjp4 In Ralstonia Eutropha Evolves To Degrade Phenoxyacetic Acid As A Sole Carbon Source, David Schlesinger, Dr. Alan R. Harker Feb 2014

Determining The Mechanism Of How The 2,4-Dichlorophenoxyacetic Acid Pathway Of Plasmid Pjp4 In Ralstonia Eutropha Evolves To Degrade Phenoxyacetic Acid As A Sole Carbon Source, David Schlesinger, Dr. Alan R. Harker

Journal of Undergraduate Research

Being that the scope of this project was much larger than anticipated I was unable to complete my research in its entirety. However I did make substantial progress and was able to answer many of my original questions.

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The Effects Of Interleukin-1a, Interleukin-6 And Tumor Necrosis Factor- A On The Growth Of Human H295r Cells, Tara Leigh Nelson, Dr. Allan M. Judd Feb 2014

The Effects Of Interleukin-1a, Interleukin-6 And Tumor Necrosis Factor- A On The Growth Of Human H295r Cells, Tara Leigh Nelson, Dr. Allan M. Judd

Journal of Undergraduate Research

Cytokines are extracellular signaling proteins or peptides that act as local mediators in cell-cell communication. They regulate several endocrine systems and function in the immune process. These agents mediate cellular proliferation within endocrine tissues, regulate hormone secretion, and control aspects of inflammation (1). Interleukin-1a (IL- 1a), IL-6 and tumor necrosis factor-a (TNF-a) are present in normal adrenal glands of rats, bovine and humans. They stimulate and inhibit adrenal hormones. Growth and differentiation of the adrenal gland may also be affected by cytokines. The study of the effects of these cytokines is important because adrenal tumors may cause hypersecretion of the …

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Phylogenetic Analysis Of Crayfish Using Astacin, Crystal Komm, Dr. Keith A. Crandall Feb 2014

Phylogenetic Analysis Of Crayfish Using Astacin, Crystal Komm, Dr. Keith A. Crandall

Journal of Undergraduate Research

Astacin is a zinc-endopeptidase, originally described as a unique enzyme and first sequenced from the crayfish Astacus astacus (Geier 97). This project aimed to gather several Astacin gene sequences from multiple taxa of crayfish and to submit them to phylogenetic analysis using PAUP (Swofford 98). PAUP would then generate trees displaying the most probable evolutionary relationships among taxa based on variation in the Astacin gene sequences.

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Independent Murine Biosynthesis Of Threonine: Expression Of A Complete Bacterial Biosynthetic Pathway In Mice, Ryan D. Mcallister, Dr. David Kooyman Feb 2014

Independent Murine Biosynthesis Of Threonine: Expression Of A Complete Bacterial Biosynthetic Pathway In Mice, Ryan D. Mcallister, Dr. David Kooyman

Journal of Undergraduate Research

Threonine is one of the 20 common amino acids found in nature. It is a limiting factor for the growth of many non-ruminant animals such as swine and mice and must be obtained from their diet. When threonine is absent from the diet of these animals, the other amino acids present cannot be fully utilized. The result is poor conversion of plant to animal protein (1). We proposed producing transgenic mice using the genes from the known five-step bacterial pathway for threonine synthesis (2). The introduction of these bacterial pathways to mice would eliminate the need for dietary supplementation of …

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Transmission Electron Microscopy Study Of Tobacco Seed Endosperm Transformed With Zein Protein Genes From Zea Mays, Susan Eldredge, Dr. Craig E. Coleman Feb 2014

Transmission Electron Microscopy Study Of Tobacco Seed Endosperm Transformed With Zein Protein Genes From Zea Mays, Susan Eldredge, Dr. Craig E. Coleman

Journal of Undergraduate Research

Zein proteins represent the prolamin (alcohol soluble) fraction of maize storage proteins. Zeins constitute approximately 50 percent of the total seed protein in maize, and therefore greatly affect the overall amino acid balance of the maize grain (1).

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Molecular Evolution Among Populations Of The Silky Pocket Mouse (Parognathus Flavus), Taylor Maxwell, Dr. Duke Rogers Feb 2014

Molecular Evolution Among Populations Of The Silky Pocket Mouse (Parognathus Flavus), Taylor Maxwell, Dr. Duke Rogers

Journal of Undergraduate Research

Mexico is classified as a “megadiversity” country, which means that it has more species of plants and animals than the vast majority of other countries in the world. For example, there are ca. 4,750 species of mammals known to science, and more than one of every seven can be found in Mexico. The reasons that Mexico has so much biodiversity are complex, but in part, it is due to the fact that the region is climatically and topographically diverse. Habitats range from lowland tropical rain forest in the south to dry deserts in the north with a multitude of intervening …

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Synthesis Of Bioconjugate Dimers Used To Probe The Structure Of Pglycoprotein, Emily Parker, Dr. Merritt B. Andrus Feb 2014

Synthesis Of Bioconjugate Dimers Used To Probe The Structure Of Pglycoprotein, Emily Parker, Dr. Merritt B. Andrus

Journal of Undergraduate Research

Chemotherapy is one of the primary treatments for cancer today. A patient’s life may depend on its efficacy, so when he or she develops multi-drug resistance (MDR) the results can be devastating. MDR, a clinical condition manifested by the failure of chemotherapy, is primarily due to the expression of P-glycoprotein (Pgp), a membrane-bound small molecule transport protein which is found normally in some cells but is greatly over expressed in drug resistant cancer cells1. It is believed that after chemotherapy drugs diffuse into the cell, Pgp effluxes them out using energy from ATP hydrolysis, thus imparting drug resistance.

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Bacterial Fingerprints, Kristilyn Rogers, Dr. Ron W. Leavitt Feb 2014

Bacterial Fingerprints, Kristilyn Rogers, Dr. Ron W. Leavitt

Journal of Undergraduate Research

Bordetellosis, or turkey coryza, is a highly contagious respiratory disease in poultry caused by Bordetella avium. Turkey growers worldwide are concerned with this disease which results in millions of dollars in losses annually to the turkey industry. Bordetellosis is readily transmitted through close contact with those already infected, or by exposure to contaminated litter or water. Infected turkeys experience, among other things, stunted growth and a predisposition for other infectious diseases. The mortality rate for bordetellosis is less than 10%. However, morbidity rates can reach 80-100% in young poults. Moreover, with concurrent infection of B. avium and Escherichia coli …

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Random Mutagenesis In Phob: A Proposed Study Of The Effects Of Mutations In Phosphate Regulation, Chad C. Lowe, Dr. William R. Mccleary Feb 2014

Random Mutagenesis In Phob: A Proposed Study Of The Effects Of Mutations In Phosphate Regulation, Chad C. Lowe, Dr. William R. Mccleary

Journal of Undergraduate Research

Within the prokaryotic cell, the intake of essential nutrients is continuously regulated by intracellular mechanisms. When fundamental nutrients become scarce, cellular stress responses are activated to enable the cell to survive in a harsh environment. Recent studies have shown a two-component regulatory mechanism which enhances Escherichia coli intracellular phosphate uptake in a phosphatepoor environment (5). This system, called the Pho system, consists of a sensor (PhoR) and an activator (PhoB). When environmental phosphate is limited, PhoR becomes autophosphorylated and in turn phosphorylates PhoB (4). The phosphorylated PhoB recognizes and binds to a consensus sequence called the “pho box” and …

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Effects Of Reverse Transcriptase And Protease Inhibitors On Lymphoid Tissue Viral Load In Murine Retrovirus Infection, Eric R. Griffiths, Dr. Greg Burton Feb 2014

Effects Of Reverse Transcriptase And Protease Inhibitors On Lymphoid Tissue Viral Load In Murine Retrovirus Infection, Eric R. Griffiths, Dr. Greg Burton

Journal of Undergraduate Research

During HIV infection, blocking viral replication has drastic effects on HIV immune complexes maintained on follicular dendritic cells (FDCs): HIV immune complexes quickly drop off FDCs to undetectable levels (1). This was a remarkable and unexpected finding since FDCs typically preserve trapped antigen for months to years. Furthermore, mice have been shown to carry infectious viral immune complexes on FDCs for periods of over nine months in the total absence of viral replication (2).

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Measles Virus And Its Interactions With Follicular Dendritic Cells, Michael J. Lloyd, Dr. Gregory F. Burton Feb 2014

Measles Virus And Its Interactions With Follicular Dendritic Cells, Michael J. Lloyd, Dr. Gregory F. Burton

Journal of Undergraduate Research

Measles virus continues to be a major cause of death in most third-world countries and a considerable threat to the health of every country. Infection with measles is thought to be associated with the fatal, late-infection disease subacute sclerosing panencephalitis (SSPE) (3). It is thought that Measles virus is retained by the body following infection until it mutates, crosses the blood-brain barrier to infect and destroy brain tissue, killing the host.

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Brain Aromatase And 5a-Reductase, Regulatory Behaviors And Testosterone Levels In Adult Rats On Phytoestrogen Diets, Scott Weber, Dr. Edwin Lephart Feb 2014

Brain Aromatase And 5a-Reductase, Regulatory Behaviors And Testosterone Levels In Adult Rats On Phytoestrogen Diets, Scott Weber, Dr. Edwin Lephart

Journal of Undergraduate Research

In certain brain regions, brain cell differentiation is influenced by hormones present at the time of development. Two hormones, estrogen (estradiol) and testosterone, play significant roles in male and female brain structure differentiation. The major androgen (testosterone) metabolizing enzymes, aromatase cytochrome P450 and 5a-reductase, play critical roles in the conversion of testosterone into estradiol and 5a-dihydrotestosterone, respectively.1

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A Comparative Study Of The Efficacy Of A New Immunoassay Of Deoxythymidine Kinase, David K. Walburger Feb 2014

A Comparative Study Of The Efficacy Of A New Immunoassay Of Deoxythymidine Kinase, David K. Walburger

Journal of Undergraduate Research

The ability to follow a cancer’s aggressiveness and response to treatment throughout the disease’s course is critical in treatment programs. The tumor markers used as indicators have not been able to consistently do this. Thymidine Kinase, an enzyme linked with cellular proliferation, has been shown to be persistently elevated in almost all cancer serums, and corresponds well with disease stage in breast cancer patients. It has also been shown that TK levels in serum, as well as in tumors, decrease drastically after treatment; subsequent rises are indicative of disease recurrence. Currently, TK levels are measured by radionucleoside phosphorylation assays. There …

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Susceptibility Of S49 Lymphoma Cell Membranes To Hydrolysis By Secretory Phospholipase A2 During Early Phase Of Apoptosis, Darin V. Allred, Kim L. O'Neill Feb 2014

Susceptibility Of S49 Lymphoma Cell Membranes To Hydrolysis By Secretory Phospholipase A2 During Early Phase Of Apoptosis, Darin V. Allred, Kim L. O'Neill

Journal of Undergraduate Research

Apoptosis is a term used to describe a programmed method of cellular suicide. This programmed cell death is a normal and very important feature of the maturation of an organism. The body uses it to tightly control the number of divisions of all types of cells in order to eliminate excess cells and develop properly. For example, our fingers are separated because embryonic cells that once joined them died during development.

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Ultrastructural Analysis Of Cartilage Matrix Fibrils, Niloufar Tabatabaei Feb 2014

Ultrastructural Analysis Of Cartilage Matrix Fibrils, Niloufar Tabatabaei

Journal of Undergraduate Research

Pulmonary Hypoplasia is a lethal neonatal disorder associated with the reduction of thoracic volume due to skeletal dysplasia.’ The homozygous recessive chondrodysplasia (cho/ cho) in mice serves as our model enabling us to demonstrate how the cartilage matrix is tied together on a molecular level. Atypically wide type II collagen fibrils have been observed in the cartilage of cho/ cho fetuses. This suggests that the mutation has altered the process by which collagen is assembled into fibrils in the extracellular matrix. Recently the cho mutation was mapped to chromosome 3 which is linked to a! (XI) collagen. Based upon this …

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Genetics And History Surrounding Chachapoyas, Peru, Joel E. Myres Feb 2014

Genetics And History Surrounding Chachapoyas, Peru, Joel E. Myres

Journal of Undergraduate Research

Anthropologists studying human diversity and distribution have long recognized that humans are the recipients of two major informational systems; one cultural and the other biological. Both these components of human diversity are inherited by organisms, be they individuals or populations, across spatial and temporal realms, and retain the ability to influence the behavior or continuance of the organism in terms of fitness. Similarly, the biological record can reflect cultural processes or transitions, such as migrations or disease, much as ethnographic studies can identify elements of cultural adoption, such as ideas or practices. In as much as these elements of culture …

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Locating Resistance To The Tomato Virus Disease “Tomov” With Rflp Markers On Chromosome 6, Heidi Lynn Stevens-Robbins, Dr. Eric N. Jellan Feb 2014

Locating Resistance To The Tomato Virus Disease “Tomov” With Rflp Markers On Chromosome 6, Heidi Lynn Stevens-Robbins, Dr. Eric N. Jellan

Journal of Undergraduate Research

Tomato yellow leaf curl virus (TYLCV) and tomato mottle virus (ToMoV), are both geminiviruses, and are considered major limiting factors in the commercially grown tomato (Lycopersicon esculentum Mill.) in Florida and the Middle East (1). These viruses have been identified as reducing yields and/or reducing fruit quality in an infected crop. TYLCV appears to have originated in Old World and has been recently identified in Florida (1). ToMoV was originally identified in Florida and has since been found throughout the Southeastern United States (2).

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The Effects Of Prenatal Phytoestrogen Exposure On Fetal Brain Calbindin Levels, Heather Taylor, Dr. Edwin Lephart Feb 2014

The Effects Of Prenatal Phytoestrogen Exposure On Fetal Brain Calbindin Levels, Heather Taylor, Dr. Edwin Lephart

Journal of Undergraduate Research

Calcium plays a major part in muscle contraction, bone growth, but especially in central nervous system (CNS) development and function. Calcium participates in neuronal growth and degeneration. For example, the CNS depends on calcium during the development of neuronal cytoskeletal structures and synapse formation. When there is an excess of calcium, it disrupts the formation and the essential synapses or connections and they fail to form correctly.

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Effects Of Prematurity On The Presence Of Weibel-Palade Bodies In Human Umbilical Vein Endothelial Cells In Situ, Niloufar Tabatabeai, Dr. John S. Gardner Feb 2014

Effects Of Prematurity On The Presence Of Weibel-Palade Bodies In Human Umbilical Vein Endothelial Cells In Situ, Niloufar Tabatabeai, Dr. John S. Gardner

Journal of Undergraduate Research

Newbom, premature infants have greater susceptibility to infection compared to older newborn infants. Although the reason for greater susceptibility to bacterial infection in premature infants is unknown, there are many reports that focus on neutrophils as the defective cell type in the immature neonatal system. However, it was recently reported by Lorant et al. that in a rat model of inflammation, neutrophils from adult rats failed to migrate efficiently in neonatal rats.’ Furthermore, we found that this defect was associated with decreased expression of Pselectin on the surface of neonatal endothelial cells in situ.

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Phylogeny Of The Order Siphonaptera Based On Molecular Data, Alison Swindle, Dr. Michael F. Whiting Feb 2014

Phylogeny Of The Order Siphonaptera Based On Molecular Data, Alison Swindle, Dr. Michael F. Whiting

Journal of Undergraduate Research

The insect order Siphonaptera (fleas) has been historically significant for thousands of years. Beginning as early as 430 B.C. outbreaks of the bubonic plague have swept across continents and killed millions of people. Before fleas were linked with the plague, they were a little known order. Karl Linne recognized only two species of fleas in his “Systemae Naturae” in 1735. From 1735 to 1897 the described species count increased slowly from two up to sixty-eight. After 1897, and the recognition that fleas may be carriers of the plague, there was a rapid escalation in the research and interest in the …

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Determining The Expression Patterns Of Developmental Genes In Tribolium, Cecily P. Vaughn, Dr. Randy Bennett Feb 2014

Determining The Expression Patterns Of Developmental Genes In Tribolium, Cecily P. Vaughn, Dr. Randy Bennett

Journal of Undergraduate Research

Development in animals is controlled by a set of genes called homeotic genes whose protein products regulate the expression of other genes. Although many homeotic genes have been locates in numerous organisms, there is still much that remains to be learned about the manner in which these genes control development. The aim of my ORCA project was to determine the expression patterns of a few key developmental genes in the red flour beetle (Tribolium castaneum).

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Effects Of Cryptogamic Crusts On Water Infiltration And Evapora· Lion Rates On Desert Soils, Eric Edgley Feb 2014

Effects Of Cryptogamic Crusts On Water Infiltration And Evapora· Lion Rates On Desert Soils, Eric Edgley

Journal of Undergraduate Research

The purpose of this study is to evaluate the impact of microbiotic (also called cryptogamic) crusts on soil surfaces on water infiltration and evaporative rates on a soil developed from fine textural lake sediments in Utah County, Utah. Twenty study plots (10 with cryptogamic cover and 10 without) are adjacent to the Camp Floyd Cemetery near Cedar Fort, Utah. They were established to evaluate the effect of cryptogamic cover on rates of water infiltration. Two aliquots of 150 ml of water were applied sequentially to each plot through standing water infiltration rings. The infiltration time of each aliquot was recorded. …

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Identification Of A Rat Gene Regulated By Dietary Selenium, Chris Cowdell Feb 2014

Identification Of A Rat Gene Regulated By Dietary Selenium, Chris Cowdell

Journal of Undergraduate Research

Various genes have been discovered which are regulated by the dietary Intake of the trace element Selenium (Se).Some of these genes code for such enzymes as glutathione peroxidase (GP J Type I iodothyronine 5′ delodinase (IDI), and selenoproteln P (Se-P). GP, is an enzyme (a selenoenzyme) which Incorporates Se in place of sulfur within residues of the amino acid cysteine. GP, Is active In the assistance of free radical elimination throughout the body by converting hydrogen peroxide (H,02 ) to oxygen (02) and water (H20). IDI is a selenoenzyme which catalyzes the conversion of the thyroid hormone thyroxine (T 4) …

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Chelex, Guanidine, And Phenol/Chloroform: A Comparison Of Extractions For Ancient Dna From Dentin Powder, J. Daniel Rasband Feb 2014

Chelex, Guanidine, And Phenol/Chloroform: A Comparison Of Extractions For Ancient Dna From Dentin Powder, J. Daniel Rasband

Journal of Undergraduate Research

Several different methods have been employed in the extraction and amplification of ancient DNA (aDNA). The work in this thesis Is an effort to compare three popular extraction techniques, chelex, guanidine/ silica slurry, and phenol/chloroform, as applied to extracting DNA from the dentin of ancient teeth. Modern and ancient samples were extracted using the three techniques. The extract was then amplified using the polymerase chain reaction (PCR). The data show that of the three extraction procedures, the most favorable results were obtained using the guanidine/silica slurry extraction technique, producing consistently good amplification. The phenol/chloroform extraction was mildly successful, showing amplification …

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Byu Microscopy Laboratory /Public School Partnership Curriculum Development, Judy L. Pickett Feb 2014

Byu Microscopy Laboratory /Public School Partnership Curriculum Development, Judy L. Pickett

Journal of Undergraduate Research

For the past five years Dr. John Gardner has been developing a microscopy outreach program for students throughout the state of Utah. I became involved in the program in the fall of 1993 and have been heavily involved in program development since that time.

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