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Molecular Taxonomy Of The Lichen Genus Heterodermia, Linda Hirschberger Apr 2000

Molecular Taxonomy Of The Lichen Genus Heterodermia, Linda Hirschberger

Seton Hall University Dissertations and Theses (ETDs)

Heterodermia is lichen consisting of a fungus and algae. Morphology and chemistry cannot provide definitive evidence for the identity of Heterodermia because various species have very similar morphologies that cannot always be distinguished. Other species only differ by the presence or absence of secondary chemicals detected. by specific chemical tests, which makes distinguishing between two species difficult. The objective of this project is to use Restriction Fragment Length Polymorphisms (RFLPs) to determine how closely related each Heterodermia species is to one another. RFLPs will also be used to determine how closely related a species is to its equal in another …

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The Hp1 Protein Family: Getting A Grip On Chromatin, J Eissenberg, Sarah C.R. Elgin Apr 2000

The Hp1 Protein Family: Getting A Grip On Chromatin, J Eissenberg, Sarah C.R. Elgin

Biology Faculty Research

HP1 was first described in Drosophila as a heterochromatin-associated protein with dosage-dependent effects on heterochromatin-induced gene silencing. Recently, membership of the HP1 protein family has expanded tremendously. A number of intriguing interactions between HP1 and other proteins have been described, implicating HP1 in gene regulation, DNA replication, and nuclear architecture.

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Molecular And Biological Characterization Of A Tanapox Virus Tnf-Binding Protein And The Complete Nucleotide Sequence Of The Psti-J Genomic Fragment, Mini Paulose-Murphy Apr 2000

Molecular And Biological Characterization Of A Tanapox Virus Tnf-Binding Protein And The Complete Nucleotide Sequence Of The Psti-J Genomic Fragment, Mini Paulose-Murphy

Dissertations

Most of the poxvirus encoded virulence factors have been identified as proteins that are secreted from infected host cells. Some of these secretory proteins impede host immune defenses. We have previously demonstrated that tanapox virus (TPV) infected cells secrete a 38 kDa glycopeptide that binds to human (h) interferon-γ, h-interleukin (IL)-2, and hIL-5. We now show an additional activity in the supernatant from TPV infected cells that down-regulates the expression of tumor necrosis factor-a (TNF-α) induced cell adhesion molecule gene expression. This activity was not detected in mock infected cells. Enzyme linked immunosorbent assays (ELISA) on primary human endothelial cells, …

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Effects Of The Zebra Mussel On Nitrogen Dynamics And The Microbial Community At The Sediment-Water Interface, Peter J. Lavrentyev, Wayne S. Gardner, Longyuan Yang Mar 2000

Effects Of The Zebra Mussel On Nitrogen Dynamics And The Microbial Community At The Sediment-Water Interface, Peter J. Lavrentyev, Wayne S. Gardner, Longyuan Yang

Biology Faculty Research

A flow-through experiment was conducted on intact cores of sediments from Saginaw Bay, Lake Huron, to examine how trophic interactions between filter-feeding bivalve mussels and microbial populations could affect nitrogen dynamics at the sediment-water interface. The zebra mussels used in this experiment removed a large proportion of protozoa and phytoplankton from the overlying water, particularly heterotrophic nanoplankton (up to 82%), while bacterial populations showed less change. A 3-fold decrease in the protozoan to bacterial carbon ratio corresponded to a 2.5-fold increase in relative ammonium removal rates as estimated from the dark loss of N-15-ammonium. Excretion by the bivalves also increased …

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The Docking Stage Of Yeast Vacuole Fusion Requires The Transfer Of Proteins From A Cis-Snare Complex To A Rab/Ypt Protein, Albert Price, Darren Seals, William Wickner, Christian Ungermann Mar 2000

The Docking Stage Of Yeast Vacuole Fusion Requires The Transfer Of Proteins From A Cis-Snare Complex To A Rab/Ypt Protein, Albert Price, Darren Seals, William Wickner, Christian Ungermann

Dartmouth Scholarship

The homotypic fusion of yeast vacuoles requires Sec18p (NSF)-driven priming to allow vacuole docking, but the mechanism that links priming and docking is unknown. We find that a large multisubunit protein called the Vam2/6p complex is bound to cis-paired SNAP receptors (SNAREs) on isolated vacuoles. This association of the Vam2/6p complex with the cis-SNARE complex is disrupted during priming. The Vam2/6p complex then binds to Ypt7p, a guanosine triphosphate binding protein of the Rab family, to initiate productive contact between vacuoles. Thus, cis-SNARE complexes can contain Rab/Ypt effectors, and these effectors can be mobilized by NSF/Sec18p-driven priming, allowing their direct …

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Identification Of Potential Vaccine And Drug Target Candidates By Expressed Sequence Tag Analysis And Immunoscreening Of Onchocerca Volvulus Larval Cdna Libraries, Michelle Lizotte-Waniewski, Wilson Tawe, David B. Guiliano, Wenhong Lu, Jing Liu, Steven A. Williams, Sara Lustigman Mar 2000

Identification Of Potential Vaccine And Drug Target Candidates By Expressed Sequence Tag Analysis And Immunoscreening Of Onchocerca Volvulus Larval Cdna Libraries, Michelle Lizotte-Waniewski, Wilson Tawe, David B. Guiliano, Wenhong Lu, Jing Liu, Steven A. Williams, Sara Lustigman

Biological Sciences: Faculty Publications

The search for appropriate vaccine candidates and drug targets against onchocerciasis has so far been confronted with several limitations due to the unavailability of biological material, appropriate molecular resources, and knowledge of the parasite biology. To identify targets for vaccine or chemotherapy development we have undertaken two approaches. First, cDNA expression libraries were constructed from life cycle stages that are critical for establishment of Onchocerca volvulus infection, the third-stage larvae (L3) and the molting L3. A gene discovery effort was then initiated by random expressed sequence tag analysis of 5,506 cDNA clones. Cluster analyses showed that many of the transcripts …

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A Developmentally Regulated Deletion Element With Long Terminal Repeats Has Cis-Acting Sequences In The Flanking Dna, Namrata S. Patil, Kathleen M. Karrer Mar 2000

A Developmentally Regulated Deletion Element With Long Terminal Repeats Has Cis-Acting Sequences In The Flanking Dna, Namrata S. Patil, Kathleen M. Karrer

Biological Sciences Faculty Research and Publications

Approximately 6000 specific DNA deletion events occur during development of the somatic macronucleus of the ciliate Tetrahymena. The eliminated Tlr1 element is 13 kb or more in length and has an 825 bp inverted repeat near the rearrangement junctions. A functional analysis of the cis-acting sequences required for Tlr1 rearrangement was performed. A construct consisting of the entire inverted repeat and several hundred base pairs of flanking DNA on each side was rearranged accurately in vivo and displayed junctional variability similar to the chromosomal Tlr1 rearrangement. Thus, 11 kb or more of internal element DNA is not required …

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Type I Nitroreductases In Soil Enterobacteria Reduce Tnt (2,4,6-Trinitrotoluene) And Rdx (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine), Christopher Kitts, Chad E. Green, Rebecca A. Otley, Marc A. Alvarez, Pat J. Unkefer Mar 2000

Type I Nitroreductases In Soil Enterobacteria Reduce Tnt (2,4,6-Trinitrotoluene) And Rdx (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine), Christopher Kitts, Chad E. Green, Rebecca A. Otley, Marc A. Alvarez, Pat J. Unkefer

Biological Sciences

Many enteric bacteria express a type I oxygen-insensitive nitroreductase, which reduces nitro groups on many different nitroaromatic compounds under aerobic conditions. Enzymatic reduction of nitramines was also documented in enteric bacteria under anaerobic conditions. This study indicates that nitramine reduction in enteric bacteria is carried out by the type I, or oxygen-insensitive nitroreductase, rather than a type II enzyme. The enteric bacterium Morganella morganii strain B2 with documented hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) nitroreductase activity, and Enterobacter cloacae strain 96-3 with documented 2,4,6-trinitrotoluene (TNT) nitroreductase activity, were used here to show that the explosives TNT and RDX were both reduced by a type …

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Optical Discrimination Of A Phytoplankton Species In Natural Mixed Populations, David F. Millie, Mark A. Moline, Oscar Schofield Mar 2000

Optical Discrimination Of A Phytoplankton Species In Natural Mixed Populations, David F. Millie, Mark A. Moline, Oscar Schofield

Biological Sciences

Developing optical detection techniques for discriminating particular phytoplankon species in mixed assemblages has long been a goal of aquatic scientists. Previously, a processing algorithm for phytoplankton absorption spectra was reported that suggested detection of the red tide dinoflagellate Gymnodinium breve was possible. The algorithm evaluated the fourth derivative of the particulate absorption spectrum of an unknown sample and compared it to a standard fourth derivative spectrum for G. breve using a similarity index. We report here the first-time application of this technique to the detection of G. breve in natural, mixed phytoplankton communities. Pigment and spectral absorption data were collected …

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A Bacteriophage-Like Particle From Bartonella Bacilliformis, Kent D. Barbian, Michael F. Minnick Mar 2000

A Bacteriophage-Like Particle From Bartonella Bacilliformis, Kent D. Barbian, Michael F. Minnick

Biological Sciences Faculty Publications

Bartonella bacilliformis and Bartonella henselae, the respective agents of Oroya fever and cat-scratch disease in humans, are known to produce bacteriophage-like particles (BLPs) that package 14 kbp segments of the host chromosome. Data from this study suggest that other Bartonella species including Bartonella quintana, Bartonella doshiae and Bartonella grahamii also contain similar BLPs, as evidenced by the presence of a 14 kbp extrachromosomal DNA element in their genomes, whereas Bartonella elizabethae and Bartonella clarridgeiae do not. A purification scheme utilizing chloroform, DNase I and centrifugation was devised to isolate BLPs from B. bacilliformis. Intact BLPs were observed by transmission electron …

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Periphyton Production On Wood And Sediment: Substratum-Specific Response To Laboratory And Whole-Lake Nutrient Manipulations, Yvonne Vadeboncoeur, David M. Lodge Mar 2000

Periphyton Production On Wood And Sediment: Substratum-Specific Response To Laboratory And Whole-Lake Nutrient Manipulations, Yvonne Vadeboncoeur, David M. Lodge

Biological Sciences Faculty Publications

Substratum heterogeneity is a large source of variability in periphyton production, but the influence of substratum on periphyton response to experimental manipulations is rarely measured. Using laboratory and whole-lake experiments, we compared area-specific primary production of periphyton on wood (epixylon) and sediment (epipelon), and tested whether periphyton on the 2 substrata responded differently to water-column fertilization. In the laboratory, natural periphyton assemblages on wood or sediment were exposed to 1 of 6 treatments in a fully factorial (light [250, 70, or 10 μmol m−2 s−1] × nutrient [control or + N and P]) experiment. We measured 14 …

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A Summer Survey Of The Birds At Two Eastern Nebraska Wetlands, Kristine T. Phipps Mar 2000

A Summer Survey Of The Birds At Two Eastern Nebraska Wetlands, Kristine T. Phipps

Biology Faculty Publications

This study compares the avian species diversity at two eastern Nebraska wetlands that differ in their relative isolation from an urban environment. Birds were surveyed by the point Count method twice weekly at each site during June of 1998. Diversity was measured using species richness and species evenness. The percentage of bird species observed that depend on wetlands for breeding was also compared. Results suggest that both species richness and evenness, as determined by the Shannon-Wiener index, were higher at the wetland located in a network of other marsh areas and agricultural land than at the suburban wetland. Immigration of …

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Reflections On Science And Technology, Ursula Goodenough Mar 2000

Reflections On Science And Technology, Ursula Goodenough

Biology Faculty Research

Science and technology are frequently confused. This essay points out the bases for this confusion and then focuses on a basic distinction, namely, that whereas science brings us information that we have little choice but to absorb and reflect upon, technology is something that humans elect to do and, hence, can also elect not to do. It is proposed that technological ethics are most cogently undertaken with scientific understanding as the linchpin and religious/artistic sensibilities as the muse.

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The Advantages Of Clonal Integration Under Different Ecological Conditions: A Community-Wide Test, Steven C. Pennings, Ragan M. Callaway Mar 2000

The Advantages Of Clonal Integration Under Different Ecological Conditions: A Community-Wide Test, Steven C. Pennings, Ragan M. Callaway

Biological Sciences Faculty Publications

The "connectedness" of clonal plants has been shown to promote survival and growth in a variety of single-species, single-factor studies, but experiments comparing the relative advantages of clonality across multiple habitats and species are rare, raising the concern that generalizations about the benefits of clonality might be biased by the particular species or habitat studied. We studied the importance of clonal integration in southeastern USA salt marsh plants, using all six of the common clonal species in the community, by following the success of intact and severed clonal fragments invading three habitat treatments. Clonal integration was most important for growth …

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Discovering Teamwork - A Novel Cooperative Learning Activity To Encourage Group Interdependence, Maureen T. Knabb Mar 2000

Discovering Teamwork - A Novel Cooperative Learning Activity To Encourage Group Interdependence, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.

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Los Coquís De Puerto Rico: Su Historia Natural Y Conservación, Rafael O. De Sá Mar 2000

Los Coquís De Puerto Rico: Su Historia Natural Y Conservación, Rafael O. De Sá

Biology Faculty Publications

As the title indicates, this well-illustrated (115 photographs and 76 illustrations) book summarizes the current knowledge about the natural history of the 16 species of Eleutherodactylus inhabiting Puerto Rico. The book consists of eight chapters (including the epilogue) and it is clearly stated that it was written to serve both the scientific community and the nonspecialist reader. The goal of bridging these two audiences is ambitious and usually difficult; however, the book has probably accomplished this goal. The technical reader, i.e., students and professional herpetologists, will find a good summary of data and enough information to continue reading with interest. …

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Brown-Headed Cowbird Brood Parasitism In Bison-Grazed And Ungrazed Tallgrass Prairie, Alexandra C. Latham '00 Feb 2000

Brown-Headed Cowbird Brood Parasitism In Bison-Grazed And Ungrazed Tallgrass Prairie, Alexandra C. Latham '00

Honors Projects

The Brown-headed Cowbird (Molothrus ater has long been associated with bison (Bos bison) in North America on the Great Plains (Friedmann 1929). As a result, I anticipated that cowbirds would parasitize host nests more frequently in the presence of bison than in their absence. I predicted that several common ground-nesting avian species, Dickcissels (Spiza americana), Grasshopper Sparrows (Ammodramus savannarum), and Eastern Meadowlarks (Sturnella magna), would suffer higher frequencies of brood parasitism in bison-grazed habitat than in ungrazed habitat on the tallgrass Konza Prairie Research Natural Area, located in northeastern Kansas. The frequency of cowbird parasitism for all species combined was …

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Biochemical And Genetic Conservation Of Fission Yeast Dsk1 And Human Srpk1, Zhaohua Irene Tang, Tiffany Kuo, Jenny Shen, Ren-Jang Lin Feb 2000

Biochemical And Genetic Conservation Of Fission Yeast Dsk1 And Human Srpk1, Zhaohua Irene Tang, Tiffany Kuo, Jenny Shen, Ren-Jang Lin

WM Keck Science Faculty Papers

Arginine/serine-rich (RS) domain-containing proteins and their phosphorylation by specific protein kinases constitute control circuits to regulate pre-mRNA splicing and coordinate splicing with transcription in mammalian cells. We present here the finding that similar SR networks exist in Schizosaccharomyces pombe. We previously showed that Dsk1 protein, originally described as a mitotic regulator, displays high activity in phosphorylating S. pombe Prp2 protein (spU2AF59), a homologue of human U2AF65. We now demonstrate that Dsk1 also phosphorylates two recently identified fission yeast proteins with RS repeats, Srp1 and Srp2, in vitro. The phosphorylated proteins bear the same phosphoepitope found in mammalian SR proteins. Consistent …

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Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt Feb 2000

Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt

Biological Sciences

Experiments were conducted to test several methods for estimating low temperature thresholds for seed germination. Temperature responses of nine weeds common in annual agroecosystems were assessed in temperature gradient experiments. Species included summer annuals (Amaranthus albus, A. palmeri, Digitaria sanguinalis, Echinochloa crus-galli, Portulaca oleracea, and Setaria glauca), winter annuals (Hirschfeldia incana and Sonchus oleraceus), and Conyza canadensis, which is classified as a summer or winter annual. The temperature below which development ceases (Tbase) was estimated as the x-intercept of four conventional germination rate indices regressed on temperature, by repeated probit analysis, …

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Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary Feb 2000

Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary

Biological Sciences Faculty Publications

Vestimentiferan tubeworms thriving in sulfidic deep-sea hydrothermal vents and cold seeps are constrained by their nutritional reliance on chemoautotrophic endosymbionts. In a recent phylogenetic study using 16S ribosomal DNA, we found that endosymbionts from vent and seep habitats form two distinct clades,vith little variation within each clade. In the present study, we used two different approaches to assess the genetic variation among biogeographically distinct vestimentiferan symbionts, DNA sequences were obtained for the noncoding, internal transcribed spacer (ITS) regions of the rRNA operons of symbionts associated with six different genera of vestimentiferan tubeworms. ITS sequences from endosymbionts of host genera collected …

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Final Envrionmental Impact Statement: Iron Point Exploration License -- Iron Point Coal Lease Tract -- Elk Creek Coal Lease Tract, Volume 1, United States Department Of Agriculture -- Forest Service, United States Departement Of The Interior -- Bureau Of Land Management Feb 2000

Final Envrionmental Impact Statement: Iron Point Exploration License -- Iron Point Coal Lease Tract -- Elk Creek Coal Lease Tract, Volume 1, United States Department Of Agriculture -- Forest Service, United States Departement Of The Interior -- Bureau Of Land Management

Environmental Assessments (CO)

The Final Environmental Impact Statement (EIS) describes the physical, biological, social, and economic resources that would be potentially affected by leasing of the Iron Point and Elk Creek Coal Lease tracts as well as issuing an exploration license for an area within and surrounding the Iron Point Coal Lease Tract. The federal decisions to be made involve the approval or disapproval of coal leasing (the Iron Point and Elk Creek tracts) and of an exploration license. Some of the key issues for these proposed actions include: the potential effects of transporting over 19 million tons of coal per year from …

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Integronlike Structures In Campylobacter Spp. Of Human And Animal Origin, Brigid Lucey, D. Crowley, P. Moloney, B. Cryan, M. Daly, F. O'Halloran, E. J. Threlfall, S. Fanning Feb 2000

Integronlike Structures In Campylobacter Spp. Of Human And Animal Origin, Brigid Lucey, D. Crowley, P. Moloney, B. Cryan, M. Daly, F. O'Halloran, E. J. Threlfall, S. Fanning

Department of Biological Sciences Publications

Resistance to antimicrobial agents used to treat severe Campylobacter spp. gastroenteritis is increasing worldwide. We assessed the antimicrobial resistance patterns of Campylobacter spp. isolates of human and animal origin. More than half (n = 32) were resistant to sulphonamide, a feature known to be associated with the presence of integrons. Analysis of these integrons will further our understanding of Campylobacter spp. epidemiology.

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Roles Of Hof1p, Bni1p, Bnr1p, And Myo1p In Cytokinesis In Saccharomyces Cerevisiae, Elizabeth Ann Vallen, J. Caviston, E. Bi Feb 2000

Roles Of Hof1p, Bni1p, Bnr1p, And Myo1p In Cytokinesis In Saccharomyces Cerevisiae, Elizabeth Ann Vallen, J. Caviston, E. Bi

Biology Faculty Works

Cytokinesis in Saccharomyces cerevisiae occurs by the concerted action of the actomyosin system and septum formation. Here we report on the roles of HOF1,BNI1, and BNR1 in cytokinesis, focusing on Hof1p. Deletion of HOF1 causes a temperature-sensitive defect in septum formation. A Hof1p ring forms on the mother side of the bud neck in G2/M, followed by the formation of a daughter-side ring. Around telophase, Hof1p is phosphorylated and the double rings merge into a single ring that contracts slightly and may colocalize with the actomyosin structure. Upon septum formation, Hof1p splits into two rings, disappearing upon cell separation. Hof1p …

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Contribution Of Autosomal Loci And The Y Chromosome To The Stress Response In Rats, Pierre Dumas, Zdenka Pausova, Vladimir Kren, Drahomira Krenova, Michal Pravenec, Marc Dumont, Daniel Ely, Monte E. Turner, Yulin Sun, Johanne Tremblay, Pavel Hamet Feb 2000

Contribution Of Autosomal Loci And The Y Chromosome To The Stress Response In Rats, Pierre Dumas, Zdenka Pausova, Vladimir Kren, Drahomira Krenova, Michal Pravenec, Marc Dumont, Daniel Ely, Monte E. Turner, Yulin Sun, Johanne Tremblay, Pavel Hamet

Biology Faculty Research

Stress is a critical contributor to cardiovascular diseases through its impact on blood pressure variability and cardiac function. Familial clustering of reactivity to stress has been demonstrated in human subjects, and some rodent models of hypertension are hyperresponsive to stress. Therefore, the present study was designed to uncover the genetic determinants of the stress response. We performed a total genome linkage search to identify the loci of the body temperature response to immobilization stress in a set of recombinant inbred strains (RIS) originating from reciprocal crosses of spontaneously hypertensive rats (SHR) with a normotensive Brown Norway Lx strain. Two quantitative …

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Stress And Developmental Stability: Vegetation Removal Causes Increased Fluctuating Asymmetry In Shrews, Alexander V. Badyaev, Kerry R. Foresman, Miguel V. Fernandes Feb 2000

Stress And Developmental Stability: Vegetation Removal Causes Increased Fluctuating Asymmetry In Shrews, Alexander V. Badyaev, Kerry R. Foresman, Miguel V. Fernandes

Biological Sciences Faculty Publications

Environmental stress can increase phenotypic variation in populations by affecting developmental stability of individuals. While such increase in variation results from individual differences in ability to buffer stress, groups of individuals and different traits may have different sensitivity to stressful conditions. For example, the sex that is under stronger directional selection for faster growth may be more sensitive to stressful conditions during development. On an individual level, stress-induced variation in a trait may be related to the strength of stabilizing selection that acts on the trait. We experimentally examined sensitivity of mandibular development to stress in a free-living population of …

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Decreased Thin Filament Density And Length In Human Atrophic Soleus Muscle Fibers After Spaceflight, Danny A. Riley, James L. W. Bain, Joyce L. Thompson, Robert H. Fitts, Jeffrey J. Widrick, Scott W. Trappe, Todd A. Trappe, David L. Costill Feb 2000

Decreased Thin Filament Density And Length In Human Atrophic Soleus Muscle Fibers After Spaceflight, Danny A. Riley, James L. W. Bain, Joyce L. Thompson, Robert H. Fitts, Jeffrey J. Widrick, Scott W. Trappe, Todd A. Trappe, David L. Costill

Biological Sciences Faculty Research and Publications

Soleus muscle fibers were examined electron microscopically from pre- and postflight biopsies of four astronauts orbited for 17 days during the Life and Microgravity Sciences Spacelab Mission (June 1996). Myofilament density and spacing were normalized to a 2.4-μm sarcomere length. Thick filament density (~1,062 filaments/μm2) and spacing (~32.5 nm) were unchanged by spaceflight. Preflight thin filament density (2,976/μm2) decreased significantly (P < 0.01) to 2,215/μm2 in the overlap A band region as a result of a 17% filament loss and a 9% increase in short filaments. Normal fibers had 13% short thin filaments. The 26% decrease in thin filaments …

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Substrate Profile In Rat Soleus Muscle Fibers After Hindlimb Unloading And Fatigue, Varvara P. Grichko, Anne R. Heywood-Cooksey, Kameha R. Kidd, Robert H. Fitts Feb 2000

Substrate Profile In Rat Soleus Muscle Fibers After Hindlimb Unloading And Fatigue, Varvara P. Grichko, Anne R. Heywood-Cooksey, Kameha R. Kidd, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Limb muscles from rats flown in space and after hindlimb unloading (HU) show an increased fatigability, and spaceflight has been shown to result in a reduced ability to oxidize fatty acids. The purpose of this investigation was to determine the effects of HU on the substrate content in fast- and slow-twitch fibers and to assess the substrate utilization patterns in single slow type I fibers isolated from control and HU animals.Asecond objective was to assess whether HU altered the ability of the heart or limb muscle to oxidize pyruvate or palmitate. After 2 wk of HU, single fibers were isolated …

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Responses Of Phytoplankton And Pfiesteria-Like Dinoflagellate Zoospores To Nutrient Enrichment In The Neuse River Estuary, North Carolina, Usa, James L. Pinckney, Hans W. Paerl, Elin Haugen, Patricia A. Tester Jan 2000

Responses Of Phytoplankton And Pfiesteria-Like Dinoflagellate Zoospores To Nutrient Enrichment In The Neuse River Estuary, North Carolina, Usa, James L. Pinckney, Hans W. Paerl, Elin Haugen, Patricia A. Tester

Faculty Publications

The recently described toxic dinoflagellate Pfiestena piscicida and morphologically similar Pfiesteria-like dinoflagellates have become a major water quality issue with possible fish mortality and reported human health implications. The linkages between accelerated nutrient loading, eutrophication, and the proliferation of this group of dinoflagellates, however, are not well established for natural Systems. Phytoplankton pnmary production may provide a key link between nutrient inputs and potential outbreaks of Pfiesteria-like biflagellated zoospores in the Neuse River Estuary, North Carolina. The impacts of nutrient (NO3- -nitrogen and PO43- -phosphorus) supply rates, sediment-water column exchange, water column mixing, and phytoplankton prey …

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Determining The Phylogenetic Relationships Among The Northern Pike (Esox Lucius), The Muskellunge (Esox Masquinongy), And The Silver Pike, Steven W. Foster Jan 2000

Determining The Phylogenetic Relationships Among The Northern Pike (Esox Lucius), The Muskellunge (Esox Masquinongy), And The Silver Pike, Steven W. Foster

Theses, Dissertations and Capstones

Prioritization of taxa has become a necessity due to limited resources available for conservation. Conservation efforts are often concentrated on those threatened and endangered species with the highest taxonomic importance. The silver pike is a rare game fish, often accounting for less than 1% of a total pike population where it is found. Although silver pike are normally found in association with northern pike, they have distinct morphological characteristics and have not been shown to hybridize with the northern pike. Still, many fisheries biologists consider the silver pike to be a color variant of the northern pike, and to date …

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The Life History Of The Cave Salamander, Eurycea Lucifuga Rafinesque, In West Virginia, Andrew James Longenecker Jan 2000

The Life History Of The Cave Salamander, Eurycea Lucifuga Rafinesque, In West Virginia, Andrew James Longenecker

Theses, Dissertations and Capstones

In West Virginia, as throughout its range, there is limited information about the life history of the cave salamander (Eurycea lucifuga). The purpose of this study was to describe the natural history of this species in West Virginia. The objectives of this study were to determine habitat selection of the cave salamander, to ascertain its environmental characteristics, and to study its reproductive and non-reproductive biology. Three study caves were located in Greenbrier County, West Virginia. All sites were examined at least once each month from May 1999 through April 2000. Caves were divided into three zones: entrance, twilight, …

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