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A Synopsis Of The Ferns And Fern Allies Of Nebraska, With Maps Of Their Distribution, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

School of Biological Sciences: Faculty Publications

An annotated list and country-by-country distribution maps are presented for the 32 species of ferns and fern allies native to Nebraska, based upon field and herbarium studies and critical evaluation of the literature. Native to the state are Isoëtes melanopoda, Selaginella rupestris, five species of Equisetum, and 25 species in 18 genera of ferns. Three native species are here verified for the first time, based upon recent collections: Matteuccia struthiopteris var. pensylvanica, Ophioglossum engelmannii, and Pellacaglabella ssp. glabella. Isoëtes melanopoda was rediscovered in 2000, the first record since 1941. Rejected are published reports of …

Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequential SepPak elution, reversed phase high performance liquid chromatography (RP-HPLC) and gel electrophoresis, the yield of the active peptide was approximately 0.1% of the total protein in the hemolymph plasma. The molecular weight, 4.2kDa, was determined by MALDI-TOF mass spectrometry. N-terminal sequencing by the Edman degradation …

Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

No abstract provided.

A Comparative Study Of The Feeding Ecology Of Chelonia Mydas (Green Turtle) And The Incidental Ingestion Of Prorocentrum Spp, Karen Gayle Holloway Adkins

Retrospective Theses and Dissertations

The diets of green turtles from five dissimilar aggregations of juvenile C. mydas on the East Coast of Florida were analyzed. C. mydas were captured by tangle net from four of the study sites and a dietary sample was collected by an esophageal flushing technique. The gut content of stranded individuals was collected for the fifth site. The vegetation in these study areas differs in varying degrees of abundance and diversity. Analysis of the samples revealed the alga types preferred by green turtles from each population and provided the basis for examination of similarities and differences in their diets.

Large …

Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá

Biology Faculty Publications

Atelopus tricolor and Atelophryniscus chrysophorus have gastromyzophorous tadpoles. Aside from specific differences, the larval chondrocrania and visceral skeletons show several shared character states, including an almost quadrangular, open chondrocranium , cornua trabeculae with expanded tips, cartilago suprarostralis as a single element, a posteriorly projected arcus subocularis quadrati, a closed muscular tunnel, and a simplified branchial basket, with only three pairs of ceratobranchiales. They are compared with diverse character states of suctorial larvae considering them as causally related to the stream life adaptations.

Firefly Flashing Is Controlled By Gating Oxygen To Light-Emitting Cells, G. S. Timmins, F. J. Robb, C. M. Wilmot, S. K. Jackson, H. M. Swartz

Dartmouth Scholarship

Although many aspects of firefly bioluminescence are understood, the mechanism by which adult fireflies produce light as discrete rapid flashes is not. Here we examine the most postulated theory, that flashing is controlled by gating oxygen access to the light-emitting cells (photocytes). According to this theory, the dark state represents repression of bioluminescence by limiting oxygen, which is required for bioluminescence; relief from this repression by transiently allowing oxygen access to the photocytes allows the flash. We show that normobaric hyperoxia releases the repression of light emission in the dark state of both spontaneously flashing and non-flashing fireflies, causing continual …

Expression Of Mslec1- And Mslec2-Antisense Genes In Alfalfa Plant Lines Causes Severe Embryogenic, Developmental And Reproductive Abnormalities, Laurence M. Brill, Cory J. Evans, Ann M. Hirsch

Biology Faculty Works

Although it has been proposed that plant lectins play a number of roles, the function of these proteins in normal plant growth and development has been unclear. To analyze the functions of putative alfalfa lectin genes, lines of transgenic alfalfa plants expressing approximately half of the open reading frame of MsLEC1 or MsLEC2, in the antisense or sense orientation, were established and analyzed. The antisense plants displayed severe abnormalities in embryogenesis, and both vegetative and reproductive development were perturbed. Some differences were observed between MsLEC1- and MsLEC2-antisense plants, and abnormalities were especially severe during the early stages of development in …

Density-Dependent Invariance, Dimensionless Life-Histories And The Energy-Equivalence Rule, E. L. Charnov, J. P. Haskell, S.K. Morgan Ernest

Biology Faculty Publications

It is suggested that Damuth’s ‘energy-equivalence rule’ for mammal populations follows from a particular population dynamics invariance rule, one which leads to similar population dynamics when various species are viewed in a particular density and rate-of-change space.

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.

High Frequency Of Extra-Pair Paternity In Eastern Kingbirds, D. L. Rowe, M. T. Murphy, R. C. Feischer, Paul G. Wolf

Biology Faculty Publications

Genetic parentage in the socially monogamous and territorial Eastern Kingbird( Tyrannust tyrannus) was examined in a central New York population by multilocus DNA fingerprinting. Extra-pair young were identified in 60% (12 of 20) of nests. Of the 64 nestlings profiled, 42% were sired by extra-pair males, but no cases of conspecific brood parasitism were detected. These results are markedly different from a previous electrophoretic study of the same species in a Michigan population, which reported 39% of nestlings were unrelated to one (typically the mother, quasiparasitismo)r both (conspecificb roodp arasitism) of the putative parents. In the New York population, extra-pairp …

Patch-Clamp Analysis Of Voltage-Activated And Chemically Activated Currents In The Vomeronasal Organ Of Sternotherus Odoratus (Stinkpot/Musk Turtle), D. A. Fadool, M. Wachowiak, J. H. Brann

Biology: Faculty Publications and Other Works

The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, -54.5 +/- 2.7 mV, N=11; input resistance, 6.7 +/- 1.4 G Omega, N=25; capacitance, 4.2 +/- 0.3 pF, N=22; means +/- …

Group Viii Spiroplasma Of Costa Rica, Kimberly M. Stewart

College of Graduate Studies: Theses & Dissertations (1964–2006)

Spiroplasma bacteria isolates are classified or identified through a series of serological tests that normally consists of screening, one-way deformation tests, cloning, antisera production, and reciprocal deformation tests. Serological tests on the spiroplasmas are followed by molecular analysis. The standard molecular analysis used for spiroplasmas has been 16S rRNA sequencing. The primary goal ofmy research was to evaluate serologically Group VIII spiroplasmas isolated from tropical Costa Rican tabanids (Diptera: Tabanidae) and to compare them to the temperate North American Group VIII spiroplasmas. A secondary goal was to evaluate both the temperate and tropical Group VIII strains by sequencing the 16S-23S …

Yield-Per-Recruit Analysis For Black Drum, Pogonias Cromis, Along The East Coast Of The United States And Management Strategies For Chesapeake Bay, Cynthia M. Jones, Brian K. Wells

OES Faculty Publications

Black drum, Pogonias cromis along the U.S. East Coast is subject to commercial and recreational harvest. However, prior to this study no modeling had been undertaken to examine the potential for overfishing in the Chesapeake Bay region. We present evidence from yield-per-recruit models that growth overfishing of black drum is unlikely under current fishing practices in this region. Particular attention was given to fishing practices in the Chesapeake Bay region where old, large fish predominate in the commercial and recreational catches (mean age=26 years: mean total length=108.4 cm; mean weight 22.1 kg). Yield-per-recruit model results showed that growth overfishing was …

An Investigation Of Captive Florida Manatee (Trichecus Manatus Latirostris) Behavior And Social Interactions, Jennifer Sadler Young

College of Graduate Studies: Theses & Dissertations (1964–2006)

Human impacts such as pollution, habitat alteration, and boating have caused many injuries and deaths of the Florida manatee, Trichechus manutus latirostris. Rehabilitation centers have been established in Florida to help return sick or injured manatees back to the wild. Manatees that are released back to the wild after undergoing rehabilitation in captivity might lose some of their abilities to survive in the wild. A factor that might alter behavior in captive individuals was examined by determining if length of time spent in captivity influenced the behavior of manatees during rehabilitation. Even though all facilities follow similar guidelines, invariable …

Developmental Tendril Morphology In Echinocystis Lobata (Michaux) Torrey And Gray (Cucurbitaceae), Theodore Bowen Guthrie

Dissertations and Theses @ UNI

Tendrils are generally defined as coiling organs used as mechanical supports and for climbing. The morphological nature of the tendril and the branching pattern of the axillary bud complex (ABC) in the family Cucurbitaceae have been the subject of investigation for over a hundred years and as of yet there is no unifying interpretation of their morphological values. The tendril in the Cucurbitaceae has been hypothesized to be homologous to a leaf, a flower, a stem, and a combination of stem and leaf. Echinocystis lobata (Michaux) Torrey and Gray was used as a model to study the ontogeny of the …

Renal Function In Suckling And Fasting Pups Of The Northern Elephant Seal, Dorian S. Houser, Daniel E E. Crocker, Paul M. Webb, Daniel P. Costa

Arts & Sciences Faculty Publications

Elephant seals fast for prolonged periods without access to water. This is made possible, in part, by reductions in urine production. However, the mechanisms involved in reducing urine production are not understood. In this study, glomerular filtration rate (GFR) was measured in five northern elephant seal pups (Mirounga angustirostris) via the inulin clearance technique. Measurements were made during day 9 and day 18–22 of nursing and the second and eighth week of the postweaning fast. Plasma aldosterone and cortisol concentrations, quantified by radioimmunoassay, were measured in eight other weanlings during the second and eighth week of the fast. …

Characterization Of Borrelia Burgdorferi Blya And Blyb Proteins: A Prophage-Encoded Holin-Like System, Christopher J. Damman, Christian H. Eggers, D. Scott Samuels

Biological Sciences Faculty Publications

The conserved cp32 plasmid family of Borrelia burgdorferi was recently shown to be packaged into a bacteriophage particle (C. H. Eggers and D. S. Samuels, J. Bacteriol. 181:7308-7313, 1999), This plasmid encodes BlyA, a 7.4-kDa membrane-interactive protein, and BlyB, an accessory protein, which were previously proposed to comprise a hemolysis system. Our genetic and biochemical evidence suggests that this hypothesis is incorrect and that BlyA and BlyB function instead as a prophage-encoded holin or holin-like system for this newly described bacteriophage, An Escherichia coli mutant containing the blyAB locus that was defective for the normally cryptic host hemolysin SheA was …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

Identification And Characterization Of Zinc-Responsive Genes In Pseudomonas Fluorescens, Thomas L. Wilson

Masters Theses

Genes responsive to elevated concentrations of zinc were identified via transposon mutagenesis in the common soil bacterium, Pseudomonas fluorescens ATCC13525. Some of these genes were essential to maintain metal homeostasis in the bacterial cell. DNA sequences of the transposon-tagged genes were determined by DNA sequencing of arbitrary PCR products. DNA sequence analysis indicated that one gene was similar to P-type ATPases responsible for transporting metal ions out of the cell. The corresponding mutant was sensitive to zinc, cadmium, and lead indicating that this gene may be responsible for defending Pseudomonas fluorescens against these metal ions. Four zinc-induced genes shared similarity …

Cadmium Induced Gene Expression And Signal Transduction Pathway, Daisuke Maki

Masters Theses

Cells respond to cadmium (Cd), a common environmental contaminate, by potentially decreasing reduced intracellular glutathione, as well as, increasing the expression of several antioxidant genes. One of these antioxidant genes, glucose-6- phosphate dehydrogenase (G6PDH), is the rate limiting enzyme of the pentose phosphate pathway. This pathway produces NADPH which is used for maintenance of reduced glutathione so, it is hypothesized that Cd should increase G6PDH expression. In this study, we demonstrate that Cd increases the level of G6PDH mRNA in primary rat hepatocytes in culture. In the presence of the antioxidants, N-acetylcysteine (NAC), Trolox, or glutathione monoethyl ester an attenuation …

Causality And Subjectivity In The Religious Quest, Ursula Goodenough

Biology Faculty Research

The dynamics of seeking causation and the dynamics of subjectivity are presented and then brought together in a consideration of the three core components of the religious quest: the search for and experience of ultimate explanations, the interiority of religious experience (“spirituality”), and the empathic experience of religious fellowship.

Long-Toed Salamanders In Harvested And Intact Douglas-Fir Forests Of Western Montana, George P. Naughton, Colin B. Henderson, Kerry R. Foresman, Rex L. Mcgraw Ii

Biological Sciences Faculty Publications

There is little known about how timber harvest practices have affected terrestrial amphibians in the northern Rocky Mountains. Especially lacking is information on the effects of revised harvest methods that fall within the framework of environmental or New Forestry. We estimated the relative abundance of a common forest amphibian, the long-toed salamander (Ambystoma macrodactylum) captured in pitfall arrays on intact, environmentally harvested, and overstory-removal harvested sites in mixed-conifer forests of western Montana. Pitfall data from 1994 through 1996 showed that previously logged sites contained significantly fewer long-toed salamanders regardless of harvest method used. The number of salamanders captured …

Role Of Dopamine D4 Receptor In The Genomic And Behavioral Effects Of Psychostimulants: Relevance To Schizophrenia, Bina Garimella

Masters Theses

The role of dopamine D4 receptors in the induction and expression of behavioral sensitization to amphetamine, cocaine and PCP was investigated in this study. Behavioral changes and genomic responses accompanying sensitization were examined using a highly selective D4 receptor antagonist, PNU-101387G. Induction and expression of behavioral sensitization to cocaine was blocked by PNU-101387G. However, the D4 antagonist did not modulate the induction and expression of behavioral sensitization to PCP. Neuroadaptive genomic responses accompanying acute and chronic effects of amphetamine and their modulation by PNU-101387G was examined by looking at alterations in the expression of two immediate-early genes: c-fos and NGFI-A. …

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

The timing and pattern of myogenesis varies among anurans that have been studied and the different pat- terns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., 1989) and they can provide infor- mation on evolutionary changes for closely related lineages within a clade. For example, we previously com- pared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick et al., 1999). We found that although the timing of myogenesis differed, …

A Comparison Study Of Astm-Ifa (Icr) Method, The Pronetic Method And Dynal Method For Detection And Enumeration Of Giardia And Cryptosproidium In Source Waters In Kentucky, Lisa Curtis Hawkins

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Lisa Curtis Hawkins on November 28, 2000.

Somite Development In Zebrafish, Heather L. Stickney, Michael J.F. Barresi, Stephen H. Devoto

Biological Sciences: Faculty Publications

A full understanding of somite development requires knowledge of the molecular genetic pathways for cell determination as well as the cellular behaviors that underlie segmentation, somite epithelialization, and somite patterning. The zebrafish has long been recognized as an ideal organism for cellular and histological studies of somite patterning. In recent years, genetics has proven to be a very powerful complementary approach to these embryological studies, as genetic screens for zebrafish mutants defective in somitogenesis have identified over 50 genes that are necessary for normal somite development. Zebrafish is thus an ideal system in which to analyze the role of specific …

H-Ns Controls Pap And Daa Fimbrial Transcription In Escherichia Coli In Response To Multiple Environmental Cues, C. A. White-Ziegler, A. Villapakkam, K. Ronaszeki, S. Young

Biological Sciences: Faculty Publications

A comparative study was completed to determine the influence of various environmental stimuli on the transcription of three different fimbrial operons in Escherichia coli and to determine the role of the histone-like protein H-NS in this environmental regulation. The fimbrial operons studied included the pap operon, which encodes pyelonephritis-associated pili (P pili), the daa operon, which encodes F1845 fimbriae, and the fan operon, which encodes K99 fimbriae. Using lacZYA transcriptional fusions within each of the fimbrial operons, we tested temperature, osmolarity, carbon source, rich medium, oxygen levels, pH, amino acids, solid medium, and iron concentration for their effects on fimbrial …

Effect Of Harvest And Effective Population Size On Genetic Diversity In A Striped Bass Population, Marilyn Diaz, David S. Wethey, James Bulak, Bert Ely

Faculty Publications

A major factor that contributes to loss of genetic variation in natural populations is a small effective population size. In species with a complex life history that involves overlapping generations and delayed maturity, the impact of infrequent annual reproductive bottlenecks is likely to be small because effective population size is defined by the number of individuals contributing to a generation and not to a single year-class. The striped bass Morone saxatilis is a longlived species with overlapping generations and age structure, whose recreational and commercial importance has made it a target of intense harvest.We analyzed allele frequency fluctuation among juvenile …

Biomechanics And Energetics In Aquatic And Semiaquatic Mammals: Platypus To Whale, Frank E. Fish

Biology Faculty Publications

A variety of mammalian lineages have secondarily invaded the water. To locomote and thermoregulate in the aqueous medium, mammals developed a range of morphological, physiological, and behavioral adaptations. A distinct difference in the suite of adaptations, which affects energetics, is apparent between semiaquatic and fully aquatic mammals. Semiaquatic mammals swim by paddling, which is inefficient compared to the use of oscillating hydrofoils of aquatic mammals. Semiaquatic mammals swim at the water surface and experience a greater resistive force augmented by wave drag than submerged aquatic mammals. A dense, nonwettable fur insulates semiaquatic mammals, whereas aquatic mammals use a layer of …

Spaceflight Effects On Single Skeletal Muscle Fiber Function In The Rhesus Monkey, Robert H. Fitts, Dominique Desplanches, Janell Romatowski, Jeffrey J. Widrick

Biological Sciences Faculty Research and Publications

The purpose of this investigation was to understand how 14 days of weightlessness alters the cellular properties of individual slow- and fast-twitch muscle fibers in the rhesus monkey. The diameter of the soleus (Sol) type I, medial gastrocnemius (MG) type I, and MG type II fibers from the vivarium controls averaged 60 ± 1, 46 ± 2, and 59 ± 2 µm, respectively. Both a control 1-G capsule sit (CS) and spaceflight (SF) significantly reduced the Sol type I fiber diameter (20 and 13%, respectively) and peak force, with the latter declining from 0.48 ± 0.01 to 0.31 ± 0.02 …