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Bioenergetic Profiles Of Isolated Mitochondria From Diapausing Embryos Of The Annual Killifish Austrofundulus Limnaeus, Jeff Duerr, Jason E. Podrabsky Jan 2008

Bioenergetic Profiles Of Isolated Mitochondria From Diapausing Embryos Of The Annual Killifish Austrofundulus Limnaeus, Jeff Duerr, Jason E. Podrabsky

Faculty Publications - Department of Biological & Molecular Science

The annual killifish, Austrofundulus limnaeus, occupy ephemeral pond habitats by producing diapausing embryos which can reduce their oxygen consumption rate by up 90% compared to developing embryos. Mitochondria isolated from whole embryos collected at 10 dpf, diapause II, post-diapause, diapause III, post-hatch larvae, and adult liver exhibited oxygen consumption rates that increased with developmental stage in the presence of glutamate or succinate. Measurements of electron transport chain activity reflected life-stage specific regulation. Minimum ETC activity was observed during diapause II: complex I activity was 12% of adult, complex II was 25% of adult, and complex IV activity was 20% of …

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An Analysis Of Tracheid Length Versus Age In A 4842-Year Old Bristlecone Pine (Pinus Longaeva D.K. Bailey) Called Prometheus, Teresa Halupnik Jan 2008

An Analysis Of Tracheid Length Versus Age In A 4842-Year Old Bristlecone Pine (Pinus Longaeva D.K. Bailey) Called Prometheus, Teresa Halupnik

Biology Dissertations - Archive

After felling, it was revealed that Prometheus, an ancient bristlecone pine (Pinus longaeva D.K. Bailey) located in the Great Basin National Park, had been the oldest living organism at over 5000 years of age. Great Basin bristlecone pines are famous for their longevity, living thousands of years under extreme conditions of temperature and moisture at high altitudes. For the majority of conifer trees, a period of rapid growth in tracheid lengths has been observed from the pith up to ten to forty years of age. Since most pine trees live for an average of 100-300 years, it was hypothesized that, …

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The Evolutionary History And Genomic Impact Of Mammalian Dna Transposons, John Kelly Pace Jan 2008

The Evolutionary History And Genomic Impact Of Mammalian Dna Transposons, John Kelly Pace

Biology Dissertations - Archive

Transposable elements (TEs) are mobile repetitive sequences that make up large fractions of mammalian genomes, including at least 45% of the human genome. Class 2, or DNA intermediate transposons, which make up approximately 3% of human nuclear DNA, have typically been overlooked in analyses of mammalian genomes and therefore remain poorly understood. Here, we carried out the first large-scale analysis of the evolutionary history of DNA transposons throughout eutherian mammal evolution. The analysis included 18 mammals from all major branches of the eutherian tree including Afrotheria, Laurasiatheria, primates, rodents and Xenarthra. We combined three different computational methods: average divergence of …

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Description Of The Immature Stages Of Methona Confusa Confusa Butler, 1873 And Methona Curvifascia Weymer, 1883 (Nymphalidae, Ithomiinae) From Eastern Ecuador, Ryan I. Hill, Luis A. Tipan Jan 2008

Description Of The Immature Stages Of Methona Confusa Confusa Butler, 1873 And Methona Curvifascia Weymer, 1883 (Nymphalidae, Ithomiinae) From Eastern Ecuador, Ryan I. Hill, Luis A. Tipan

College of the Pacific Faculty Articles

Here we describe the complete life history for Methona confusa confusa Butler, 1873 and Methona curvifascia Weymer, 1883 from eastern Ecuador. Each stage from egg to pupa is described and illustrated. Descriptions of first instar chaetotaxy and instar durations are also reported. Both species were found feeding on Brunfelsia grandiflora schultesii Plowman. Mature M. confusa larvae have 12 transverse bands that are all yellow in color, including one on segment A9 as observed for M. megisto and M. themisto. In contrast, M. curvifascia lacks a transverse band on segment A9, having 11 transverse bands in total that are white in …

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Mitochondria In Energy-Limited States : Mechanisms That Blunt The Signaling Of Cell Death., Steven Hand, Michael Menze Jan 2008

Mitochondria In Energy-Limited States : Mechanisms That Blunt The Signaling Of Cell Death., Steven Hand, Michael Menze

Faculty and Staff Scholarship

Cellular conditions experienced during energy-limited states – elevated calcium, shifts in cellular adenylate status, compromised mitochondrial membrane potential – are precisely those that trigger, at least in mammals, the mitochondrion to initiate opening of the permeability transition pore, to assemble additional protein release channels, and to release pro-apoptotic factors. These proapototic factors in turn activate initiator and executer caspases. How is activation of mitochondria-based pathways for the signaling of apoptotic and necrotic cell death avoided under conditions of hypoxia, anoxia, diapause, estivation and anhydrobiosis? Functional trade-offs in environmental tolerance may have occurred in parallel with the evolution of diversified pathways …

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Display Of An Inedible Prop As A Signal Of Aggression? Adaptive Significance Of Leaf-Display By The Turquoise-Browed Motmot, Eumomota Superciliosa, Troy G. Murphy Jan 2008

Display Of An Inedible Prop As A Signal Of Aggression? Adaptive Significance Of Leaf-Display By The Turquoise-Browed Motmot, Eumomota Superciliosa, Troy G. Murphy

Biology Faculty Research

The incorporation of an inedible object (prop) into a behavioral display is rare among birds. Only four avian taxa have been reported to display with a prop, and in all studied species, prop use has been found to play a role in mate acquisition. However, little is known about the context and adaptive significance of prop use by the motmots. Both male and female motmots perform a leaf-display, whereby a leaf is held horizontally in the tip of the bill for an extended period. I collected observational data on leaf-display by the turquoise-browed motmots (Eumomota superciliosa) to investigate …

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Effect Of Three Orobanche Spp. Extracts On Some Local Phytopathogens, Agrobacterium And Erwinia, Ismail M. Saadoun, Khalid M. Hameed, Fouad Al-Momani, Qotaiba Ababneh Jan 2008

Effect Of Three Orobanche Spp. Extracts On Some Local Phytopathogens, Agrobacterium And Erwinia, Ismail M. Saadoun, Khalid M. Hameed, Fouad Al-Momani, Qotaiba Ababneh

Turkish Journal of Biology

Tissues of the spikes of Orobanche spp. contain phenols and mannitol pathways, and it seems that it is very resistant, or may be immune, to bacterial infection. Therefore extracts of 3 Orobanche species, O. cernua, O. crenata, and O. egyptiaca, were evaluated for their antibacterial activity against local isolates of crown gall (Agrobacterium) and soft rot (Erwinia) phytopathogens. Extract of O. cernua showed the highest activity against both pathogens with clear inhibition zones of 8-24 mm and 12-16 mm in diameters, respectively. When the inhibitory action of 100 mg/ml concentration of the 3 Orobanche species extract on local isolates of …

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A History Of The Biology Department, Omer R. Larson Jan 2008

A History Of The Biology Department, Omer R. Larson

UND Departmental Histories

This departmental history was written on the occasion of the UND Quasquicentennial in 2008.

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Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes Jan 2008

Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Compared to insects, little is known about innate immunity in ticks. This chapter addresses the molecular processes that recognize non-self and the cellular and molecular processes mobilized to phagocytose, engulf, inhibit or kill invaders. We discuss the receptors that recognize pathogen associated molecular patterns (PAMPs) and the putative up-regulation of regulatory cascades that lead, ultimately, to cellular or molecular responses. We describe the molecular events that activate the cellular processes and the array of humoral factors that are mobilized against invading organisms, including antimicrobial peptides, proteases and protease inhibitors, lectins, coagulation factors and others. Special attention is directed to the …

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Strong Genetic Differentiation Among Neighboring Populations Of A Locally Endemic Primrose, L. Bjerregaard, Paul G. Wolf Jan 2008

Strong Genetic Differentiation Among Neighboring Populations Of A Locally Endemic Primrose, L. Bjerregaard, Paul G. Wolf

Biology Faculty Publications

Maguire primrose is a locally endemic plant of northern Utah, USA, with a total known range of less than 20 km2. A previous study found evidence for strong differentiation among local populations at 4 allozyme loci. Here we reexamined populations using 165 AFLP loci and found further evidence of unusually strong genetic structure. We also found an apparently fixed nucleotide difference between populations for a noncoding region of chloroplast DNA, mirroring the patterns seen for AFLP loci. Furthermore, we tested the hypothesis that the current population structure is the result of breeding barriers between plants from different populations. We made …

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Androgenesis In Anther Culture Of Lithuanian Spring Barley (Hordeum Vulgare L.) And Potato (Solanum Tuberosum L.) Cultivars, Rita Asakaviciute Jan 2008

Androgenesis In Anther Culture Of Lithuanian Spring Barley (Hordeum Vulgare L.) And Potato (Solanum Tuberosum L.) Cultivars, Rita Asakaviciute

Turkish Journal of Biology

An anther culture method was used for the production of doubled haploids (DHs) in Lithuanian barley and potato cultivars that were directly regenerated from embryoids (Caredda´s method) were applied to determine androgenic potential according to the green regenerant yield and other morphogenetic factors. Green DH regenerants were obtained in 3 Lithuanian spring barley cultivars (´Aidas´, ´Alsa´, and ´Auksiniai´) out of 10 studied. The highest rate of embryoid formation was determined in cv. ´Auksiniai 3´, representing 580.0 embryoids per 100 responding anthers. The potato cultivar ´Nida´ was superior in terms of the rate of responding anthers (17.4%). The highest rate of …

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Rapid Measurements Of Periphytic Responses To Nutrients Using Pam Fluorimetry, Sarah Brooke Whorley Jan 2008

Rapid Measurements Of Periphytic Responses To Nutrients Using Pam Fluorimetry, Sarah Brooke Whorley

Master's Theses and Doctoral Dissertations

Water quality monitoring has traditionally been done by measuring periphytic algal biomass that has grown on fertilized or unfertilized patches of habitat produced by nutrientdiffusing substrata (NDS). This method requires the destruction of the accumulated periphyton communities and thus does not allow for convenient monitoring through time. Optical fluorometric methods of estimating biomass and photosynthetic activity have been used in saline environments, but generally not over different nutrient treatments and not for a substantial duration. This study evaluated the use of a pulse amplitude modulated (PAM) fluorometer for measuring biomass and photosynthetic activity in conjunction with NDS over several weeks. …

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Structure-Function Analysis Of The Drosophila Stubble Type Ii Transmembrane Serine Protease, Rachel Morgan Jan 2008

Structure-Function Analysis Of The Drosophila Stubble Type Ii Transmembrane Serine Protease, Rachel Morgan

Electronic Theses and Dissertations

Hormonally-triggered regulatory hierarchies play a major role in organismal development. Disruption of a single member of such a hierarchy can lead to irregular development and disease. Therefore, knowledge of the members involved and the mechanisms controlling signaling through such pathways is of great importance in understanding how resulting developmental defects occur. Type II transmembrane serine proteases (TTSPs) make up a family of cell surface-associated proteases that play important roles in the development and homeostasis of a number of mammalian tissues. Aberrant expression of TTSPs is linked to several human disorders, including deafness, heart and respiratory disease and cancer. However, the …

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Tmdl Bioassessment Sampling Of Benthic Macroinvertebrates For Lake Jesup And Lake Seminary, Gloria Eby Jan 2008

Tmdl Bioassessment Sampling Of Benthic Macroinvertebrates For Lake Jesup And Lake Seminary, Gloria Eby

Electronic Theses and Dissertations

The objective of this study was to obtain a bioassessment using benthic macroinvertebrates to meet TMDL (Total Maximum Daily Load) criteria for an oligotrophic (Lake Seminary) and an eutrophic (Lake Jesup) freshwater system in Seminole County, Florida. Monthly sampling of the benthic macroinverterbrate communities provided important biological data necessary to construct TMDL protocol and trophic state. Since macroinvertebrates are near the base of the food chain, they not only provide a critical role in the natural flow of energy and cycling of nutrients through the food web, but also provide a good indication of water quality by their presence and …

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Growth And Survival Of Bacteria In Simulated Martian Conditions, Bonnie Berry Jan 2008

Growth And Survival Of Bacteria In Simulated Martian Conditions, Bonnie Berry

Electronic Theses and Dissertations

Escherichia coli and Serratia liquefaciens, two common microbial spacecraft contaminants known to replicate under low atmospheric pressures of 25 mb, were tested for growth and survival in simulated martian conditions. Stressors of high salinity, low temperature, and low pressure were screened alone and in combination to determine how they might affect microbial activity. Growth and survival of E. coli and S. liquefaciens under low temperatures (30, 20, 10, or 5 °C) with increasing concentrations (0, 5, 10, or 20 %) of three salts believed to be present on the surface of Mars (MgCl2, MgSO4, NaCl) were monitored over 7 d. …

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Cis-Regulatory Analysis Of The Pigment Cell Differentiation Gene Polyketide Synthase, David Rogers Jan 2008

Cis-Regulatory Analysis Of The Pigment Cell Differentiation Gene Polyketide Synthase, David Rogers

Electronic Theses and Dissertations

The analysis of Gene Regulatory Networks (GRNs) is essential to understanding the complete process of embryo development. Elucidating every gene regulatory circuit from maternal regulatory inputs all the way to the activation of differentiation gene batteries is an important step in increasing our understanding of developmental biology. In this work I study the cis-regulatory architecture of a pigment cell differentiation gene, polyketide synthase (SpPks) in the sea urchin Strongylocentrotus purpuratus. SpPks encodes an enzyme that is responsible for the biosynthesis of the sea urchin pigment echinochrome in larval pigment cells. The analysis of the promoter of a differentiation gene will …

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Polyaniline Nanofiber-Based Gas Sensors, Zhe-Fei Li, Frank D. Blum, Massimo F. Bertino, Chang-Soo Kim Jan 2008

Polyaniline Nanofiber-Based Gas Sensors, Zhe-Fei Li, Frank D. Blum, Massimo F. Bertino, Chang-Soo Kim

Chemistry Faculty Research & Creative Works

There has been recent interest in conducting polymers that have very promising chemical and electrical applications. Some of these polymers have shown great potential for use in sensors.1 Polyaniline is one particular example of a prospective material. In our laboratory, we have studied the synthesis of polyaniline nanofibers. We have carried out one-pot syntheses to obtain polyaniline nanofibers in aqueous solutions where the polymerization was influenced by γ-radiation2 or UV-radiation.3 This polymer can also be patterned with an appropriate photo mask. In our present report, polyaniline nanofiber thin film sensors have been fabricated in one step by employing UV-irradiation and …

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Factors Influencing The Distribution Of Overwintered Bullfrog Tadpoles (Rana Catesbeiana) In Two Small Ponds, S. E. Hargis, M.-K. Harr, C. J. Henderson, W. J. Kim, Geoffrey R. Smith Jan 2008

Factors Influencing The Distribution Of Overwintered Bullfrog Tadpoles (Rana Catesbeiana) In Two Small Ponds, S. E. Hargis, M.-K. Harr, C. J. Henderson, W. J. Kim, Geoffrey R. Smith

Faculty Publications

No abstract provided.

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Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, C. J. Dibble, Geoffrey R. Smith, J. A. Lemos-Espinal Jan 2008

Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, C. J. Dibble, Geoffrey R. Smith, J. A. Lemos-Espinal

Faculty Publications

No abstract provided.

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A Tribute To Robert Benson Gordon, Gerard Hertel, Virginia Gordon Hatch, Robert L. Gordon Jan 2008

A Tribute To Robert Benson Gordon, Gerard Hertel, Virginia Gordon Hatch, Robert L. Gordon

Gordon Natural Area History & Strategic Plan Documents

No abstract provided.

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Cytotoxicity Of Diepoxybutane And Epichlorohydrin In Relation To Stages Of The Cell Cycle, Megan L. Watts Jan 2008

Cytotoxicity Of Diepoxybutane And Epichlorohydrin In Relation To Stages Of The Cell Cycle, Megan L. Watts

Honors Theses

Work conducted in the Millard Biochemistry Research Laboratory examines the dual nature of molecules as carcinogens and anti-tumor agents through the molecular mechanisms of duplex DNA damage by bifunctional alkylating agents. Diepoxybutane (DEB) and epichlorohydrin (ECH) are polar molecules that form covalent DNA interstrand lesions by cross-linking the N7 position of deoxyguanosine residues. A recent experiment indicated that ECH preferentially targets nuclear DNA over mitochondrial DNA, whereas DEB shows similar rates of lesion formation for both loci. It was concluded that preferential targeting of nuclear DNA results from relatively poor uptake of ECH across the mitochondrial membrane. The objective of …

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Gliotoxin Production In Aspergillus Fumigatus, Susan Musyimi Jan 2008

Gliotoxin Production In Aspergillus Fumigatus, Susan Musyimi

Theses and Dissertations

Aspergillus fumigalus is a ubiquitous fungus that causes an infection called aspergillosis in immune-compromised surgery patients (Latge, 2001, 384; Bok et al. 2006). Aspergillosis cases have increased in the past decade due to the increasing number of patients undergoing immunosuppressive therapy and receiving organ transplants (Bok et al. 2006). Although there is still disagreement as to the causative agent of the symptoms accompanying aspergillosis, many scientists suspect that the compound, gliotoxin, plays a major role, hi this study, we compared the amounts of gliotoxin produced from clinical and environmental isolates of A. fumigatus. We hypothesized that the amount of gliotoxin …

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Microhabitat Selection By The Tortoiseshell Limpet, Tectura Testudinalis (Müller), In Tide Pools On The Mid-Maine Coast, Emily R. Lyczkowski Jan 2008

Microhabitat Selection By The Tortoiseshell Limpet, Tectura Testudinalis (Müller), In Tide Pools On The Mid-Maine Coast, Emily R. Lyczkowski

Honors Theses

Microhabitat selection of the limpet Tectura testudinalis, an important grazer along the rocky Maine coast is examined using both mensurative and manipulative experiments. T. testudinalis substrate selection is essential to its survival in the unpredictable and harsh regime of the intertidal zone. At three sites studied in the Gulf of Maine, T. testudinalis selectively inhabits tidal pools and vertically oriented substrates. Both of these microhabitats reduce the degree of environmental stress (desiccation, extreme temperature, and hypersaline conditions) and predation experienced by individuals. Differences among sites are common, indicating the importance of varying environmental factors in regulating and influencing habitat selection …

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A Genetic Assessment Of The Red Squirrel In Illinois: Natives, Immigrants, Or Exotics?, William Beatty Jan 2008

A Genetic Assessment Of The Red Squirrel In Illinois: Natives, Immigrants, Or Exotics?, William Beatty

Masters Theses

A small population ofred squirrels (Tamiasciurus hudsonicus) has existed in Iroquois County, Illinois since the 1970' s. The origin of this population is unknown, but some accounts suggest they are the offspring of released red squirrels from Minnesota. Alternatively, they may be a remnant Illinois population or more recent immigrants from Indiana. Finally, this population could reflect a mixed ancestry of the above scenarios. Mitochondrial DNA (mtDNA) was utilized to determine the genetic relationships among red squirrel populations in Illinois, Indiana, Michigan, Minnesota, and Wisconsin. My results showed low levels of haplotype diversity and nucleotide diversity in the Illinois sample. …

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Beneficial Effects Of Estradiol Are Mediated Through Apoe, Aseem Hussain Jan 2008

Beneficial Effects Of Estradiol Are Mediated Through Apoe, Aseem Hussain

Masters Theses

Estradiol is the primary premenopausal hormone circulating in women. It is a powerful hormone in the female body since it sends signals to the brain, regulates ovulation and menstrual cycle and acts on the nervous syste~ heart, breast and many other tissues in the body. However all estradiol production is stopped after menopause. Post menopausal women can develop a host of neurodegenerative diseases such as Alzheimer's disease. If the onset of progressive dementia is after menopause during loss of estradiol, it seems logical to assume that the lack of estradiol should have a big role to play in the pathogenesis …

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Tracing Sperm In Multiply-Mated Female Anastrepha Suspensa, (Diptera:Tephridae), Preeti Dhakal Jan 2008

Tracing Sperm In Multiply-Mated Female Anastrepha Suspensa, (Diptera:Tephridae), Preeti Dhakal

Masters Theses

Anastrepha suspensa females have four different sites of sperm storage in their reproductive tract, may mate with more than one male, and store sperm in differing amounts in each organ after copulation. In order to study the dynamics of sperm storage patterns and subsequent paternity outcomes, a method was developed for both genotyping and quantifying sperm in the spermathecae. Spermathecae were isolated and sonicated to remove maternal cells, and subsequently crushed between two microslides to release sperm from the capsule. After DNA isolation, microsatellite loci could be amplified by PCR for fragment analysis. A newly developed method was then used …

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Artificial Riffles As A Stream Remediation Technique, Bethany S. Harrington Jan 2008

Artificial Riffles As A Stream Remediation Technique, Bethany S. Harrington

Masters Theses

No abstract provided.

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Influence Of Seed Source On Vegetative And Reproductive Performance Of Three Common Prairie Grasses Common In Grassland Restoration, Matt Burmeister Jan 2008

Influence Of Seed Source On Vegetative And Reproductive Performance Of Three Common Prairie Grasses Common In Grassland Restoration, Matt Burmeister

Masters Theses

Though tallgrass prairie once covered 250 million acres of the midwestem U.S, now less than one percent· of this original area is left. In recent years the restoration and reconstruction of tallgrass prairie has become more popular throughout the prairie region. There is evidence that local and distant populations may both be practical seed sources for ecological restoration projects. To address this basic issue in restoration, I tested the how performance of three grass species from different locations was affected by the distance from the restored area. Three species, Andropogon gerardii, Sorghastrum nutans and Panicum virgatum, of perennial grasses common …

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Comparative Study Between Wild Rice (Oryza Rufipogon) And Domesticated Rice (Oryza Sativa Ssp Japonica) Chromosome 8 Centromere, Soham Aso Jan 2008

Comparative Study Between Wild Rice (Oryza Rufipogon) And Domesticated Rice (Oryza Sativa Ssp Japonica) Chromosome 8 Centromere, Soham Aso

Theses, Dissertations and Culminating Projects

Rice has one of the simplest of the monocotyledonous genomes analyzed to date. The Oryza sativa genome is made of 12 chromosomes and has a total length of 430 MB. It is highly syntenic amongst other cereals. Therefore, genetic distances of these organisms are surprisingly very similar, meaning that genomic recombinations in each cereal occur at much the same frequency despite the differences in their genome size. The reason for this synchrony in recombinations may be due to similar lengths of gene-rich and gene-rare regions. This study focuses on the gene-rare repetitive centromeric region of rice chromosome 8. Although the …

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Proxy-Based Reconstructions Of Hemispheric And Global Surface Temperature Variations Over The Past Two Millennia, Michael E. Mann, Scott Rutherford Jan 2008

Proxy-Based Reconstructions Of Hemispheric And Global Surface Temperature Variations Over The Past Two Millennia, Michael E. Mann, Scott Rutherford

Arts & Sciences Faculty Publications

Following the suggestions of a recent National Research Council report [NRC (National Research Council) (2006) Surface Temperature Reconstructions for the Last 2,000 Years (Natl Acad Press, Washington, DC).], we reconstruct surface temperature at hemispheric and global scale for much of the last 2,000 years using a greatly expanded set of proxy data for decadal-to-centennial climate changes, recently updated instrumental data, and complementary methods that have been thoroughly tested and validated with model simulation experiments. Our results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context. Recent warmth appears anomalous for at least …

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