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2013

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Defining Species Concepts: Testing Species Boundaries Of Sceloporus Grammicus, Daniel H. Chappell, Dr. Jack W. Sites Oct 2013

Defining Species Concepts: Testing Species Boundaries Of Sceloporus Grammicus, Daniel H. Chappell, Dr. Jack W. Sites

Journal of Undergraduate Research

Species concepts are the methods biologists use to name and describe species. There are many important reasons for having an empirically based species concept. Species definitions are important to the fields of population biology and phylogenetics.

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Use Of Esem And Energy-Dispersive X-Ray Microanalysis To Study Leaf Surfaces Of Austrian Pine, Joseph Donaldson, Dr. Wilford M. Hess Oct 2013

Use Of Esem And Energy-Dispersive X-Ray Microanalysis To Study Leaf Surfaces Of Austrian Pine, Joseph Donaldson, Dr. Wilford M. Hess

Journal of Undergraduate Research

The following is a report of an investigation on the effects of air pollution on Austrian pine needles. The report will state the initial question, how the report was carried out, the results of the investigation, and our conclusions. Additionally, it will report on publication and presentation of the research.

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Sequencing The Mammoth Cytochrome B Gene: A Genetic Look Into The History Of Prehistoric Columbian Mammoths, Shaun Odell, Dr. Scott Woodward Oct 2013

Sequencing The Mammoth Cytochrome B Gene: A Genetic Look Into The History Of Prehistoric Columbian Mammoths, Shaun Odell, Dr. Scott Woodward

Journal of Undergraduate Research

During the excavation process associated with the reconstruction of Cleveland reservoir dam near the Huntington Canyon area of UT, the massive skeleton of a Columbian mammoth was unearthed. Excavation of the remains ensued, and bone samples from this prehistoric mammal were sent to the Molecular Archaeogenetic Research facility at Brigham Young University. These samples were studied in hopes of unlocking many of the mysteries associated with this ancient animal.

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Volume Cxxxi, Number 4, October 11, 2013, Lawrence University Oct 2013

Volume Cxxxi, Number 4, October 11, 2013, Lawrence University

The Lawrentian

No abstract provided.

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Can A Flea See? An Investigation Of Flea Opsin (Flopsin), Sean David Taylor, Dr. Michael F. Whiting Oct 2013

Can A Flea See? An Investigation Of Flea Opsin (Flopsin), Sean David Taylor, Dr. Michael F. Whiting

Journal of Undergraduate Research

Visual pigments are responsible for conferring visual perceptual abilities to animals. Various pigments are tuned to absorb light of different wavelengths and to provide contrast and movement perception. All pigments consist of an opsin protein and a chromophore molecule, usually a carotene derivative. Interactions between the chromophore and amino acid residues of opsin fine-tune visual pigments for the absorption of different wavelengths. Opsin variants can tune visual pigments to absorb wavelengths in the ultraviolet, blue, green, and red regions of the spectrum (Briscoe and Chittka 2001).

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Phylogeny And Conservation Of The Utah Land Snail Oreohelix Peripherica (Gastropoda: Pulmonata: Camaenidae), Ashley Nelson, Dr. Keith A. Crandall Oct 2013

Phylogeny And Conservation Of The Utah Land Snail Oreohelix Peripherica (Gastropoda: Pulmonata: Camaenidae), Ashley Nelson, Dr. Keith A. Crandall

Journal of Undergraduate Research

This study of the Oreohelix peripherica land snail is a continuation of a study sponsored last year by ORCA. In 1993, Ecosearch, Inc. suggested that O. p. wasatchensis, located at Rainbow Gardens near Ogden, deserved being upgraded to having an endangered status according to the US Endangered Species Act because of its reduced area of occurrence and the depletion of its habitat. The phylogenetic hypothesis gathered from the data obtained in last year’s study suggests that the Rainbow Gardens samples are not endemic to that area because they are genetically similar to other populations from different localities. Since the population …

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Testing Cognition In Amazona Spp, Heidi Francis, Dr. Steven L. Peck Oct 2013

Testing Cognition In Amazona Spp, Heidi Francis, Dr. Steven L. Peck

Journal of Undergraduate Research

Animal intelligence has been studied for years, yet very few people are aware that parrots are ranked near the top with regards to cognition. For almost 20 years Dr. Irene Pepperberg has been teaching African Grey parrots to communicate using language, these birds then use English words to verbally answer questions testing their intelligence level. (Pepperberg, 1995) The teaching method used to do this is called the Model/Rival technique. For my research I chose to test whether this same technique could be used to teach a different species of parrot. Because of their speaking ability and large brain sizes comparable …

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Patterns Of Paternity In Clutches Of Giant Amazon River Turtles, Podocnemis Expansa, From Venezuela, R. Brigham Dastrup, Dr. Jack W. Sites, Devon E. Pearse Oct 2013

Patterns Of Paternity In Clutches Of Giant Amazon River Turtles, Podocnemis Expansa, From Venezuela, R. Brigham Dastrup, Dr. Jack W. Sites, Devon E. Pearse

Journal of Undergraduate Research

In recent years, molecular genetic data have shown that multiple paternity occurs in groups of offspring in many taxa. Though multiple paternity has been found in a wide variety of turtles (Pearse and Avise 2001), limited clutch size and/or small number of total clutches assayed has limited the evaluation of the frequency of multiple paternity within the population or the relative contributions of the respective sires. I have analyzed data from 32 clutches of the giant river turtle Podocnemis expansa from the Orinoco River in Venezuela and present here results on 29 of these clutches. Large clutch sizes of this …

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Homing Behavior Of The Limpet Species Collisella Scabra Living On The Limpet Species Lottia Gigantea, David Baugh, Dr. Lee F. Braithwaite Oct 2013

Homing Behavior Of The Limpet Species Collisella Scabra Living On The Limpet Species Lottia Gigantea, David Baugh, Dr. Lee F. Braithwaite

Journal of Undergraduate Research

Limpets are one-shelled marine mollusks that live on rocky beaches in the intertidal zone. The limpet species Collisella scabra is also found living on the shell of the limpet species L. gigantea. C. scabra exhibits an interesting phenomenon known as homing. This means that while not feeding, C. scabra are always found on the same spot on the rock or shell where they live. The C. scabra leave this spot, known as a home scar, to feed, but always return to it after they are done feeding. In this research, Chris Miller, Bryant Low, Christian Armstrong, and I examined the …

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Chemical Disinfection Of Mycobacterium Ulcerous, Brandon John Webb, Dr. Richard Robison Oct 2013

Chemical Disinfection Of Mycobacterium Ulcerous, Brandon John Webb, Dr. Richard Robison

Journal of Undergraduate Research

Mycobacterium ulcerans is the causative agent of Buruli ulcer, a disfiguring disease of the skin and muscle tissue, whose prevalence has grown exponentially in recent decades. An ulcerative disease similar to leprosy, Buruli ulcer is characterized by a superficial infection of the subcutaneous fat layer that results in large lesions that often spread to cover an entire limb. Although most severe in Third World countries, cases of M. ulcerans infection have been reported in 33 countries on five continents. According to World Health Organization statistics, the recent rise in incidence of the disease has been so pronounced that Buruli ulcer …

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Chondrogenic Differentiation Of Adult Hepatic Stem Cells: Investigating Candidates For Osteoarthritis Treatment, Jaron Coombs, David Sonntag, Dr. Laura Bridgewater Oct 2013

Chondrogenic Differentiation Of Adult Hepatic Stem Cells: Investigating Candidates For Osteoarthritis Treatment, Jaron Coombs, David Sonntag, Dr. Laura Bridgewater

Journal of Undergraduate Research

Osteoarthritis is a painful disease associated with the breakdown of articular cartilage, the protective protein coating of the major joints of the body. Over 20 million Americans are affected by this pervasive disease which is associated with the overuse of joints and aging. Osteoarthritis occurs when the proteins that compose articular cartilage are degraded by repetitive use and injury. These actions can lead to swelling, tearing, or flaking off of the cartilage at the surface of the bone. When cartilage loses its integrity in this manner the amount of friction in the joint greatly increases and the patient begins to …

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Comparative Study Of Total Antioxidant Activity Between The Fruit Momordica Cochinchinensis (Gac) And Its’ Major Carotenoid Constituents, Katherine Secrest, Dr. Kim O'Neill Oct 2013

Comparative Study Of Total Antioxidant Activity Between The Fruit Momordica Cochinchinensis (Gac) And Its’ Major Carotenoid Constituents, Katherine Secrest, Dr. Kim O'Neill

Journal of Undergraduate Research

The red fruit Momordica cochinchinensis (gac) grows indigenously throughout Southeast Asia and possesses naturally high levels of provitamin A carotenoids, beta-carotene and lycopene. In much of Southeast Asia, rural populations suffer from chronic vitamin A deficiency.1 Currently, government programs distribute vitamin A capsules as supplements, but long-term solutions lie in food-based alternatives. At this time, gac fruit is only consumed during annual festivals when the red pulp of the fruit is used to color rice. Consumption of gac fruit has been shown to significantly increase plasma beta-carotene concentrations and could provide an inexpensive, food-based alternative to improving the vitamin A …

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Ecology Of Two High Copy Plasmids, Ermira Pazolli, Dr. Alan Harker Oct 2013

Ecology Of Two High Copy Plasmids, Ermira Pazolli, Dr. Alan Harker

Journal of Undergraduate Research

Plasmids are genetic entities residing in the cell. They can vary in size and genetic content. There are alternate views about plasmids, but the consensus one is that they are genetic elements that are transferred from cell to cell, thus conferring resistance or performing some other function advantageous to the cell. The primary purpose of this study was to investigate the behavior of plasmids as individuals ‘forced’ to cooperate under selective pressure. In the first phase, we had to extract the plasmids in large quantities and construct two similar models. Due to time constraint and other unforeseen obstacles, we have …

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Analysis Of Hnf1-Beta As A Possible Regulatory Protein For The Transcription Of The Col11a2 Collagen Gene, Nicholas M. Orme, Dr. Laura C. Bridgewater Oct 2013

Analysis Of Hnf1-Beta As A Possible Regulatory Protein For The Transcription Of The Col11a2 Collagen Gene, Nicholas M. Orme, Dr. Laura C. Bridgewater

Journal of Undergraduate Research

Cartilage is a highly specialized form of connective tissue that functions as a template for most skeletal structures and aids in supporting the tension and pressure common to most animal joint function. Abnormal cartilage formation often results from defective collagen DNA and can lead to several skeletal diseases including dwarfism, cleft palate and osteoarthritis. The purpose of this research was to investigate the regulatory role of HNF proteins in the transcription of the Col11a2 gene which codes for a collagen protein found in cartilage.

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The Implications Of Subtype Diversity Of Hiv-1 For Vaccine Development, Ryan Peterson, Dr. Keith A. Crandall Oct 2013

The Implications Of Subtype Diversity Of Hiv-1 For Vaccine Development, Ryan Peterson, Dr. Keith A. Crandall

Journal of Undergraduate Research

HIV’s ability to infect a host and grow without killing the host allows the virus to accumulate genetic diversity. Over time, HIV has diverged into a number of subtypes, differing up to 30% in their nucleic acids (2). For this reason, one of the greatest problems with vaccine development is that different subtypes express different protein variants (3). With the increase of HIV recombination and human travel, geographical patterns subtypes are becoming mixed, thus allowing the virus to explore new genetic variants and evade vaccine effectiveness (5).

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Antigenotoxic Effects Of N-Acetylcysteine On Benzo[A]Pyrene Induced Dna Damage In Hepg2 Cells As Measured By The Alkaline Comet Assay, Loni A. O'Neil, M. Todd O'Neil, Dr. Kim L. O'Neill Oct 2013

Antigenotoxic Effects Of N-Acetylcysteine On Benzo[A]Pyrene Induced Dna Damage In Hepg2 Cells As Measured By The Alkaline Comet Assay, Loni A. O'Neil, M. Todd O'Neil, Dr. Kim L. O'Neill

Journal of Undergraduate Research

A major factor involved in the risk of developing cancer with the probability of enhancing or suppressing carcinogens is dietary composition. A chemoprevention approach to cancer means preventing this disease by the administration of one or several compounds. For a number of years, N-acetylcysteine (NAC) has shown in studies to be an effective chemopreventive agent, but there have also been some studies disproving the effectiveness of NAC.1, 2 This is because NAC has different functions in different cell types. Because of this, we decided to test the effectiveness of NAC against DNA damage in human HepG2 cells and to determine …

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Investigation Into The Mechanisms Associated With Angiogenesis And Metastasis, Rachelle R. Olsen, Dr. Kim L. O'Neill Oct 2013

Investigation Into The Mechanisms Associated With Angiogenesis And Metastasis, Rachelle R. Olsen, Dr. Kim L. O'Neill

Journal of Undergraduate Research

Angiogenesis, the development and differentiation of new blood vessels from pre-existing vasculature, is tightly controlled during physiological processes including wound healing, growth, and development. Angiogenesis is also associated with several human malignancies including arthritis, psoriasis, and cancer. Angiogenesis, which provides a source of nutrients and a waste outlet for biological products, is absolutely required for a tumor to grow larger than a few millimeters in size. Blood vessels formed by angiogenesis are young and immature and can facilitate metastasis, the spread and subsequent growth of primary tumor cells to distal body sites.

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Anterior-Posterior Limb Position Is Dependent On The Relative Timing Of Key Embryonic Events, Tyler Prestwich, Dr. Michael Stark Oct 2013

Anterior-Posterior Limb Position Is Dependent On The Relative Timing Of Key Embryonic Events, Tyler Prestwich, Dr. Michael Stark

Journal of Undergraduate Research

To better understand embryonic events leading to the determination of limb position along the anterior-posterior (A-P) axis, we compared pre-limb bud stage developmental morphology of three vertebrate organisms: chicken, goose and swan. These organisms were selected because of the differences each exhibit with regard to the A-P location of the forelimbs, or more specifically, the number of cervical vertebrae. By observing disparities between the embryonic morphologies of the different species, we were able to identify specific morphological distinctions that correlate with A-P patterning. Based on the data obtained, we hypothesize a mechanism whereby a delay in embryonic “differentiation” in relationship …

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A Col2a1 Mutation Leads To Increased Degradation Of Type Ii Collagen In Articular Cartilage: A Murine Model For Osteoarthritis, Peter Crane, Dr. Robert Seegmiller Oct 2013

A Col2a1 Mutation Leads To Increased Degradation Of Type Ii Collagen In Articular Cartilage: A Murine Model For Osteoarthritis, Peter Crane, Dr. Robert Seegmiller

Journal of Undergraduate Research

Normal articular cartilage is characterized by a resilient collagen and proteoglycan matrix interdispersed with chondrocytes. Collagen type II is the most abundant collagen found in the matrix and is responsible for providing tensile strength to the tissue. The highly conserved Col2a1 gene is responsible for coding all type II collagen á-helix chains.1 The process of enzymatic MMP cleavage is a natural part of collagen recycling, but has been observed to be upregulated in articular cartilage of osteoarthritis (OA) patients. It is hypothesized that further denaturation (unwinding) of enzymatically cleaved collagen takes place following enzymatic cleavage by MMP. Because increased degraded …

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Inferring The Relative Resilience Of Alternative States, David G. Angeler, Craig R. Allen, Carmen Rojo, Miguel Alvarez-Cobelas, Salvador Sánchez-Carrillo Oct 2013

Inferring The Relative Resilience Of Alternative States, David G. Angeler, Craig R. Allen, Carmen Rojo, Miguel Alvarez-Cobelas, Salvador Sánchez-Carrillo

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Ecological systems may occur in alternative states that differ in ecological structures, functions and processes. Resilience is the measure of disturbance an ecological system can absorb before changing states. However, how the intrinsic structures and processes of systems that characterize their states affects their resilience remains unclear. We analyzed time series of phytoplankton communities at three sites in a floodplain in central Spain to assess the dominant frequencies or “temporal scales” in community dynamics and compared the patterns between a wet and a dry alternative state. The identified frequencies and cross-scale structures are expected to arise from positive feedbacks that …

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Board Of Trustees Minutes, October 11, 2013, Coastal Carolina University Oct 2013

Board Of Trustees Minutes, October 11, 2013, Coastal Carolina University

Board of Trustees Meeting Minutes

No abstract provided.

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Whalesong 2013-10-11, N/A N/A Oct 2013

Whalesong 2013-10-11, N/A N/A

Whalesong

No abstract provided.

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Growth Of Tropical Dasyatid Rays Estimated Using A Multi-Analytical Approach, Owen R. O'Shea, Matias Braccini, Rory Mcauley, Conrad W. Speed, Mark G. Meekan Oct 2013

Growth Of Tropical Dasyatid Rays Estimated Using A Multi-Analytical Approach, Owen R. O'Shea, Matias Braccini, Rory Mcauley, Conrad W. Speed, Mark G. Meekan

Fisheries Research Articles

We studied the age and growth of four sympatric stingrays: reticulate whipray, Himanutra uarnak (n=19); blue mask, Neotrygon kuhlii (n=34); cowtail, Pastinachus atrus (n=32) and blue-spotted fantail, Taeniura lymma (n=40) rays at Ningaloo Reef, a fringing coral reef on the north-western coast of western Australia. Age estimates derived from band counts within sectioned vertebrae ranged between 1 and 27 years (H. uarnak, 1 - 25 yrs.; N. kuhlii, 1.5 - 13 yrs.; P. atrus, 1 - 27 yrs. and T. lymma, 1 -11 yrs.). Due to limitations of sample sizes, we combined several analytical methods …

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The New Hampshire, Vol. 103 [104], No. 10 (Oct. 11, 2013), The New Hampshire Oct 2013

The New Hampshire, Vol. 103 [104], No. 10 (Oct. 11, 2013), The New Hampshire

The New Hampshire Print Edition

An independent student produced newspaper from the University of New Hampshire. This volume was printed as 103, but it is the 104th volume in the series. This was corrected in pencil.

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High Field Breakdown Characteristics Of Carbon Nanotube Thin Film Transistors, Man Prakash Gupta, Ashkan Behnam, Feifei Lian, David Estrada, Eric Pop, Satish Kumar Oct 2013

High Field Breakdown Characteristics Of Carbon Nanotube Thin Film Transistors, Man Prakash Gupta, Ashkan Behnam, Feifei Lian, David Estrada, Eric Pop, Satish Kumar

Materials Science and Engineering Faculty Publications and Presentations

The high field properties of carbon nanotube (CNT) network thin film transistors (CN-TFTs) are important for their practical operation, and for understanding their reliability. Using a combination of experimental and computational techniques we show how the channel geometry (length LC and width WC) and network morphology (average CNT length Lt and alignment angle distribution θ) affect heat dissipation and high field breakdown in such devices. The results suggest that when WC ≥ Lt, the breakdown voltage remains independent of WC but varies linearly with LC. The breakdown power varies …

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Endogenous Human Mdm2-C Is Highly Expressed In Human Cancers And Functions As A P53-Independent Growth Activator, Danielle R. Okoro, Nicoleta Arva, Chong Gao, Alla Polotskaia, Cindy Puente, Melissa Rosso, Jill Bargonetti Oct 2013

Endogenous Human Mdm2-C Is Highly Expressed In Human Cancers And Functions As A P53-Independent Growth Activator, Danielle R. Okoro, Nicoleta Arva, Chong Gao, Alla Polotskaia, Cindy Puente, Melissa Rosso, Jill Bargonetti

Publications and Research

Human cancers over-expressing mdm2, through a T to G variation at a single nucleotide polymorphism at position 309 (mdm2 SNP309), have functionally inactivated p53 that is not effectively degraded. They also have high expression of the alternatively spliced transcript, mdm2-C. Alternatively spliced mdm2 transcripts are expressed in many forms of human cancer and when they are exogenously expressed they transform human cells. However no study to date has detected endogenous MDM2 protein isoforms. Studies with exogenous expression of splice variants have been carried out with mdm2-A and mdm2-B, but the mdm2-C isoform has remained virtually unexplored. We addressed the cellular …

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The Possible Role Of Brain Angiotensin Ii In The Reduced Growth Of Spontaneously Hypertensive Rats, Daniel R. Jensen, Dr. James P. Porter Oct 2013

The Possible Role Of Brain Angiotensin Ii In The Reduced Growth Of Spontaneously Hypertensive Rats, Daniel R. Jensen, Dr. James P. Porter

Journal of Undergraduate Research

The “Spontaneously Hypertensive Rat” strain (SHR) was bred to be innately hypertensive. This hypertension arises in part from over-activity of the brain Renin-Angiotensin system.1 Interestingly, the mean body weight of SHR is significantly reduced compared with the normotensive Wistar-Kyoto strain from which it originates. There are indications that high levels of exogenous Angiotensin II (ANG II) introduced in the brains of normotensive rats inhibit weight gain, and in some cases promote weight loss and/or wasting.2 The mechanism of this effect is not clearly understood, though some studies have shown that high levels of exogenous ANG II can induce anorexia or …

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A Phylogeny Of Robber Flies (Diptera: Asilidae) At The Subfamilial Level: Molecular Evidence, Seth Mikaya Bybee, Dr. Michael Whiting Oct 2013

A Phylogeny Of Robber Flies (Diptera: Asilidae) At The Subfamilial Level: Molecular Evidence, Seth Mikaya Bybee, Dr. Michael Whiting

Journal of Undergraduate Research

Robber flies (Diptera: Asilidae) comprise one of the largest groups of extant flies (Hull, 1962). Asilids constitute more than 500 genera (Woodley, 1989) and more than 5500 species (Lehr, 1988) with a worldwide distribution except Antarctica. Species range in size from less than one centimeter to nearly eight centimeters in length, and their prey consist of both small and large insects caught largely in flight. Asilid color patterns are simple: usually black, gray, or bronze, although some more colorful species appear to mimic bees and wasps. All members of the group, including the problematic group Leptogastrinae (thread-waisted robber flies), form …

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Molecular Phylogeny Of The Rodent Genus Liomys: Evidence From The Mitochondrial Cytochrome B Gene, Victoria L. Vance, Dr. Duke S. Rogers Oct 2013

Molecular Phylogeny Of The Rodent Genus Liomys: Evidence From The Mitochondrial Cytochrome B Gene, Victoria L. Vance, Dr. Duke S. Rogers

Journal of Undergraduate Research

The number of species described in the world greatly underestimates its biodiversity, especially in some of the areas more rich in diversity such as Mexico. Once the biodiversity in a region is understood, the issues of management and conservation can be addressed. Spiny pocket mice of the genus Liomys are members of the rodent family Heteromyidae and are grouped with the genus Heteromys in the subfamily Heteromyinae. The genus Liomys has a rather broad geographic distribution that extends from Texas to Panama and consists of five recognized species: L. irroratus, L. pictus, L. spectabilis, L. salvini, and L. adespersus.

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Does Camkii Regulate Exocytosis Through Its Binding To Syntaxin?, Stephen M. Merino, Dr. Dixon Woodbury Oct 2013

Does Camkii Regulate Exocytosis Through Its Binding To Syntaxin?, Stephen M. Merino, Dr. Dixon Woodbury

Journal of Undergraduate Research

Neurons use chemical messengers called neurotransmitters to communicate with muscles and other neurons. In the axon terminal of a neuron, neurotransmitters are stored in synaptic vesicles. Neurotransmitter is released from the neuron through a process called exocytosis. In exocytosis, synaptic vesicles fuse with the cell membrane and neurotransmitter is released from the cell. During exocytosis, important proteins in both the synaptic vesicle membrane and cell membrane called SNARE proteins bind to one another. These proteins are required for exocytosis. Exocytosis and subsequent neurotransmitter release is regulated by Ca2+. The mechanism by which Ca2+ regulates exocytosis is poorly understood.

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