Biology Commons^™

Chemical Constitutents And Cytotoxicity Of Some Tanzanian Wild Mushrooms, V. Nyigo, L. D. Baraza, M. H. H. Nkunya, S. J. M. Mdachi, C. C. Joseph, A. Waziri

Tanzania Journal of Science

The sterol ergosterol and ergosta-4,22-diene-3β,7α-diol, together with 4-hydroxybenzaldehyde were isolated from the mushroom species Polyporus molluscensis, Cantharellus isabelinus, C. symoensii and a Podaxis species. Their structures were established on the basis of spectroscopic data. The ethanol extracts of mushroom samples of Agaricus sp. and Termitomyces letestui also showed cytotoxicity against the brine shrimp larvae.

Influence Of Fructose On The Mechanisms For Ethanol-Induced Hypertriglyceridaemia, I. Onyesom

Tanzania Journal of Science

Twelve adult albino rabbits with an average weight of 1.42 kg were purchased and divided equally into the normal saline, ethanol and ethanol+fructose-treated groups. The ethanol-treated group orally received 1.5 g (40%) ethanol/kg body weight as single daily dose, while the ethanol +fructose-treated animals also received the same ethanol dose, but were given in addition, 0.25 gfructose/kg body weight after about 10 min of the ethanol administration. The normal saline-treated rabbits were given the equivalent amount of normal saline in lieu of ethanol. The animals were exposed to these various treatments along with their usual feeding pattern for a regular …

Use Of Hot Air Engine To Generate Electricity From Biogas: A Critique For Rural Development In Tanzania, L. L. N. Mkiramweni, P. Msaki, I. B. Mshoro

Tanzania Journal of Science

Rural electrification has high national priority because of several reasons. First, more than 90 per cent of the populations in Tanzania have no access to grid electricity and about 80% of this population lives in rural areas. Second, the poverty alleviation projects demand the incorporation of use of electricity in different economic projects. Third, a combination of high prices of fuel and environmental degradation and deforestation demand use of alternative renewable energy sources. The aim of this paper is to give a critical review and selected a suitable renewable energy by considering its ability to provide affordable, reliable and adequate …

Tracking Changes In Bioavailable Fe Within High-Nitrate Low-Chlorophyll Oceanic Waters: A First Estimate Using A Heterotrophic Bacterial Bioreporter, Robert Michael Mckay, C. E. Mioni, S. M. Handy, M. J. Ellwood, M. R. Twiss, P. W. Boyd, S. W. Wilhelm

Biological Sciences Faculty Publications

It is conventional knowledge that heterotrophic bacteria play a key role in the biogeochemical cycling of oceanic carbon. However, only recently has their role in marine iron ( Fe) biogeochemical cycles been examined. Research during this past decade has demonstrated an inextricable link between Fe chemistry and the biota, as >99% of Fe in marine systems is complexed to organic chelates of unknown but obviously biotic origin. Here we present a novel approach to assess and compare Fe bioavailability in low Fe HNLC waters using a bioluminescent bacterial reporter that quantitatively responds to the concentration of bioavailable Fe by producing …

Impact Of Phytoplankton On The Biogeochemical Cycling Of Iron In Subantarctic Waters Southeast Of New Zealand During Fecycle, Robert Michael Mckay, S. W. Wilhelm, J. Hall, D. A. Hutchins, M. M. D. Al-R Shaidat, C. E. Mioni, S. Pickmere, D. Porta, P. W. Boyd

Biological Sciences Faculty Publications

During austral summer 2003, we tracked a patch of surface water infused with the tracer sulfur hexafluoride, but without addition of Fe, through subantarctic waters over 10 days in order to characterize and quantify algal Fe pools and fluxes to construct a detailed biogeochemical budget. Nutrient profiles characterized this patch as a high-nitrate, low-silicic acid, low-chlorophyll (HNLSiLC) water mass deficient in dissolved Fe. The low Fe condition was confirmed by several approaches: shipboard iron enrichment experiments and physiological indices of Fe deficiency (F(v)/F(m) < 0.25, Ferredoxin Index < 0.2). During FeCycle, picophytoplankton (0.2-2 mu m) and nanophytoplankton (2-20 mu m) each contributed >40% of total chlorophyll. Whereas the picophytoplankton accounted for similar to 50% of total primary production, they …

Ranging Patterns And Habitat Utilization Of Northern River Otters, Lontra Canadensis, In Missouri: Implications For The Conservation Of A Reintroduced Species, Deborah Dorothy Boege-Tobin

Dissertations

I studied the spacing patterns and habitat utilization by reintroduced northern river otters, Lontra canadensis, at two sites in Missouri because previous studies of otters indicate, plasticity of a species social structure will likely be due to the tactics employed in acquiring resources in any given area. Seven hypotheses were tested by employing radio-tracking, habitat assessment and geographic information system approaches: (1) home range (HR) and core area (CA) size differ by sex; (2) HR and CA size differ in breeding vs. non-breeding seasons; (3) percent range overlap differs by sex; (4) habitat utilization, as indicated by latrine use, …

The Use Of Antibiotic Resistance Profiles To Access The Source Of Fecal Contamination In The Rowan County, Kentucky Watershed, Logan Harrison Burns

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 by Logan Harrison Burns on December 15, 2005.

The Relationship Between Frq-Protein Stability And Temperature Compensation In The Neurospora Circadian Clock, Peter Ruoff, Jennifer J. Loros, Jay C. Dunlap

Dartmouth Scholarship

Temperature compensation is an important property of all biological clocks. In Neurospora crassa, negative-feedback regulation on the frequency (frq) gene's transcription by the FRQ protein plays a central role in the organism's circadian pacemaker. Earlier model calculations predicted that the stability of FRQ should determine the period length of Neurospora's circadian rhythm as well as the rhythm's temperature compensation. Here, we report experimental FRQ protein stabilities in frq mutants at 20 degrees C and 25 degrees C, and estimates of overall activation energies for mutant FRQ protein degradation. The results are consistent with earlier model predictions, i.e., temperature compensation of …

Response Of Stress Levels In Domestic Canines To Calming Pheromone, Kathleen Barrett

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Exposure To Methamphetamine And Phencyclidine During Development And Subsequent Behavioral Change, Takehiro Minamoto

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 by Takehiro Minamoto on December 2, 2005.

Limits Of Temperature Tolerance Of Leishmania Enriettii And Leishmania Hertigi In A Real-Time Pcr Assay, Christina Salinas

Theses & Dissertations

Protozoans of the genus Leishmania are intracellular parasites found across five continents. They cycle between a promastigote form inside the digestive tracts of blood-feeding female sand flies and an amastigote form within mammalian host macrophages. Temperature is an important factor that must be defeated in order for the parasites' survival and continuance. This paper studies the limits of temperature tolerance by Leishmania enriettii and Leishmania hertigi. It was hypothesized that a correlation would exist between the limits of temperature tolerance to body temperature of their host. I explored growth characteristics at 21,27,29, 33, 35, 37, and 39° C. It was …

Select Listeria Monocytogenes Subtypes Commonly Found In Foods Carry Distinct Nonsense Mutations In Inla, Leading To Expression Of Truncated And Secreted Internalin A, And Are Associated With A Reduced Invasion Phenotype For Human Intestinal Epithelial Cells, K. K. Nightingale, K. Windham, K. E. Martin, M. Yeung, M. Wiedmann

Biological Sciences

The surface protein internalin A (InlA) contributes to the invasion of human intestinal epithelial cells by Listeria monocytogenes. Screening of L. monocytogenes strains isolated from human clinical cases (n=46), foods (n=118), and healthy animals (n=58) in the United States revealed mutations in inlA leading to premature stop codons (PMSCs) in L. monocytogenes ribotypes DUP-1052A and DUP-16635A (PMSC mutation type 1), DUP-1025A and DUP-1031A (PMSC mutation type 2), and DUP-1046B and DUP-1062A (PMSC mutation type 3). While all DUP-1046B, DUP-1062A, DUP-16635A, and DUP-1031A isolates (n=76) contained inlA PMSCs, ribotypes DUP-1052A and DUP-1025A ( …

[Accepted Article Manuscript Version (Postprint)] Identification And Functional Characterization Of Arabidopsis Peroxin4 And The Interacting Protein Peroxin22, Bethany Zolman, Melanie Monroe-Augustus, Illeana Silva, Bonnie Bartel

Biology Department Faculty Works

Peroxins are genetically defined as proteins necessary for peroxisome biogenesis. By screening for reduced response to indole-3-butyric acid, which is metabolized to active auxin in peroxisomes, we isolated an Arabidopsis thaliana peroxin4 (pex4) mutant. This mutant displays sucrose-dependent seedling development and reduced lateral root production, characteristics of plant peroxisome malfunction. We used yeast two-hybrid analysis to determine that PEX4, an apparent ubiquitinconjugating enzyme, interacts with a previously unidentified Arabidopsis protein, PEX22. A pex4 pex22 double mutant enhanced pex4 defects, confirming that PEX22 is a peroxin. Expression of both Arabidopsis genes together complemented yeast pex4 or pex22 mutant defects, whereas expression …

Bartonella Bacilliformis Groel: Effect On Growth Of Human Vascular Endothelial Cells In Infected Cocultures, Laura S. Smitherman, Michael F. Minnick

Biological Sciences Faculty Publications

Bartonella are the only bacteria known to induce angioproliferative lesions of the human vasculature and liver during infection. Previous work from our lab suggests that GroEL participates in the mitogenic response observed in HUVEC cultures supplemented with the soluble fraction of Bartonella bacilliformis. Work in this study shows that exposure to high concentrations of the fraction is actually cytotoxic for HUVECs. To analyze this phenomenon, live B. bacilliformis-HUVEC cocultures were employed to study the effect of excess bacterial GroEL on the host cell during active infection. Four B. bacilliformis strains were generated to produce varying levels of GroEL. HUVEC cocultures …

Aquatic Animal Health Subprogram: Technical Guidelines For The Translocation Of Live Aquatic Animals - With Reference To Barramundi Nodavirus, Brian Jones

Fisheries Research Reports

FRDC Project No. 2005/640

A workshop was conducted involving input from most jurisdictions. Technical issues including hazard identification and risk management associated with the translocation of live finfish were documented.

A series of recommendations, which resulted from the workshop process, will be progressed through the National Aquatic Animal Health Technical Working group and the Aquatic Animal Health Committee.

The Eggshell Structures Of Ringed Turtle - Doves (Streptopelia Risoria), Natalie Ellen Hubbard

Biology Theses - Archive

The avian egg provides nutrients and protects the growing embryo from physical and microbial harm. Structures fundamental to the protection are the membrane layers, which are tightly meshed networks of collagen fibers, and the eggshell, which is composed of calcite crystals, (CaC03). The eggs of Ringed Turtle-Dove and commercially bred chickens were selected for the study. Eggs of commercially bred chickens are twice in length and width of the dove eggs. Features analyzed are components of quality and strength of eggshells included shell thickness, membrane thickness, and concentration and size of vesicles. A comparative study of the bird eggs was …

Reproductive Behaviors Of Two Congeneric, Sympatric Jumping Spiders: Gene Flow Barriers And Polyandry, Stacey Nicole Gingras

Biology Theses - Archive

This two part study compares aspects of jumping spider reproductive behavior and their implications 1) as gene flow barriers during the process of speciation and 2) in the occurrence of polyandry. Courtship behaviors of Phidippus audax and P. carolinensis were observed. P. carolinensis displays simple courtship behavior when compared to the visually complex behavior of P. audax. P. carolinensis males appear to be incorporating a vibratory element into their courtship display, and a possible stridulatory organ, located on the male pedipalp, is described. Large differences in courtship display, complexity of courtship badges, and phenologies between the species most likely prevent …

Study Of The Expression Pattern Of A Possible Pseudogene And A Functional Retrogene In Drosophila, Aditi Bhardwaj

Biology Theses - Archive

Gene duplication occurs when a mutation leads to the copying of a region of DNA that contains a functional gene. After duplication, there will be two copies of the gene in the genome. Gene duplication can have deleterious effects but it can also be the source of novelty. It has been acknowledged for a long time that selection may be relaxed for one copy rendering that locus free to mutate and discover new functions. Another of the fates of duplication of special notice is the formation of a pseudogene. Pseudogenes have been defined as nonfunctional sequences of genomic DNA originally …

Sal-Site: Integrating New And Existing Ambystomatid Salamander Research And Informational Resources, Jeramiah J. Smith, Srikrishna Putta, John A. Walker, D. Kevin Kump, Amy K. Samuels, James R. Monaghan, David W. Weisrock, Chuck Staben, S. Randal Voss

Biology Faculty Publications

Salamanders of the genus Ambystoma are a unique model organism system because they enable natural history and biomedical research in the laboratory or field. We developed Sal-Site to integrate new and existing ambystomatid salamander research resources in support of this model system. Sal-Site hosts six important resources: 1) Salamander Genome Project: an information-based web-site describing progress in genome resource development, 2) Ambystoma EST Database: a database of manually edited and analyzed contigs assembled from ESTs that were collected from A. tigrinum tigrinum and A. mexicanum, 3) Ambystoma Gene Collection: a database containing full-length protein-coding sequences, 4) Ambystoma Map and Marker …

Smooth Muscle Adherens Junctions Associated Proteins Are Stable At The Cell Periphery During Relaxation And Activation, Thomas J. Eddinger, Jessen D. Schiebout, Darl R. Swartz

Biological Sciences Faculty Research and Publications

This study was performed to determine the stability of the adherens junction (AJ)-associated proteins at the smooth muscle cell (SMC) plasma membrane during relaxing and activating conditions. Dog stomach, ileum, colon, and trachea tissues were stored in Ca²⁺-free PSS or regular PSS or were activated in 10 μM carbachol in PSS before rapid freezing. The tissues were subsequently sectioned and immunoreacted using antibodies for vinculin, talin, fibronectin, and caveolin to determine their cellular distribution in these tissues under these conditions. In all four tissues and under all three conditions, the distribution of these four proteins remained localized to …

Avian Hosts For West Nile Virus In St. Tammany Parish, Louisiana, 2002, Nicholas Komar, Nicholas A. Panella, Stanley A. Langevin, Aaron C. Brault, Manuel Amador, Eric Edwards, Jennifer C. Owen

Faculty Publications

West Nile virus (WNV) infections in free-ranging birds were studied in Slidell, St. Tammany Parish, Louisiana, after a human encephalitis outbreak peaked there in July 2002. Seroprevalence in resident, free-ranging wild birds in one suburban site was 25% and 24% in August and October, respectively, indicating that most transmission had ceased by early August. Mortality rates, seroprevalence rates, host competence, and crude population estimates were used in mathematical models to predict actual infection rates, population impacts, and importance as amplifying hosts for several common passerine birds. Northern cardinal (Cardinalis cardinalis) and house sparrow (Passer domesticus) were the principal amplifying hosts, …

Disentangling Above‐ And Below‐Ground Competition Between Lianas And Trees In A Tropical Forest, Stefan A. Schnitzer, Mirjam E. Kuzee, Frans Bongers

Biological Sciences Faculty Research and Publications

1. Light is thought to be the most limiting resource in tropical forests, and thus above‐ground competition is commonly accepted as the mechanism that structures these communities. In many tropical forests, trees compete not only with other trees, but also with lianas, which compete aggressively for below‐ground resources and thus may limit tree growth and regeneration.
2. Using a replicated experiment, we tested the relative strengths of above‐ and below‐ground competition from lianas on tree saplings in a disturbed forest in Côte d’Ivoire with a heterogeneous canopy and relatively high light penetration. We planted seedlings of three tree species and subjected them …

Climatic Unpredictability And Parasitism Of Caterpillars: Implications Of Global Warming, John Stireman, Lee Dyer, D. Janzen, M. Singer, J. Lill, R. Marquis, R. Ricklefs, G. Gentry, W. Hallwachs, P. Coley, J. Barone, H. Greeney, H. Connahs, P. Barbosa, H. Morais, I. Diniz

Biology Department Faculty Works

Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar–parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps …

Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall

Faculty Publications

Freshwater crayfish have served as model organisms for over 125 years in scientific research, from areas such as neurobiology and vision research to conservation biology and evolution. Recently, evolutionary histories in the form of phylogenies have served as a critical foundation for testing hypotheses in such diverse research areas as well. In this article, I review the amazing diversity of freshwater crayfish, especially in a phylogenetic context and explore how these evolutionary histories have informed crayfish biology and can be used powerfully in the future to guide research in a diversity of areas. Throughout the article, I draw on examples …

Hybridization Of Lythrurus Fasciolaris (Cope) And Lythrurus Umbratilis (Girard) (Cypriniformes: Cyprinidae) In The Ohio River Basin, Robert L. Hopkins Ii

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 by Robert L. Hopkins, II on November 14, 2005.

The Depressive Effect Of PI On The Force-Pca Relationship In Skinned Single Muscle Fibers Is Temperature Dependent, Edward Patrick Debold, Janell Romatowski, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Increases in P_i combined with decreases in myoplasmic Ca2+ are believed to cause a significant portion of the decrease in muscular force during fatigue. To investigate this further, we determined the effect of 30 mM P_ion the force-Ca²⁺ relationship of chemically skinned single muscle fibers at near-physiological temperature (30°C). Fibers isolated from rat soleus (slow) and gastrocnemius (fast) muscle were subjected to a series of solutions with an increasing free Ca²⁺ concentration in the presence and absence of 30 mM P_iat both low (15°C) and high (30°C) temperature. In slow fibers, 30 mM …

Ego-1, A Putative Rna-Dependent Rna Polymerase, Is Required For Heterochromatin Assembly On Unpaired Dna During C. Elegans Meiosis, Eleanor M. Maine, Jessica Hauth, Thomas Ratliff, Valarie E. Vought, Xingyu She, William G. Kelly

Biology - All Scholarship

During meiosis in C. elegans, unpaired chromosomes and chromosomal regions accumulate high levels of histone H3 lysine 9 dimethylation (H3K9me2), a modification associated with facultative heterochromatin assembly and the resulting transcriptional silencing [1, 2]. Meiotic silencing of unpaired DNA may be a widely conserved genome defense mechanism [3–5]. The mechanisms of meiotic silencing remain unclear, although both transcriptional and posttranscriptional processes are implicated [3–5]. Cellular RNA-dependent RNA polymerases (RdRPs) function in development and RNA-mediated silencing in many species [3, 6, 7] and in heterochromatin assembly in S. pombe [3, 8]. There are four C. elegans RdRPs, including two with known …

Plumage Convergence In Picoides Woodpeckers Based On A Molecular Phylogeny, With Emphasis On Convergence In Downy And Hairy Woodpeckers, Amy C. Weibel, William S. Moore

Biological Sciences Faculty Research Publications

Adult and juvenile plumage characters were traced onto a well-resolved molecular based phylogeny for Picoides woodpeckers, and a simple phylogenetic test of homology, parallelism, and convergence of plumage characters was performed. Reconstruction of ancestral character states revealed multiple events of independent evolution of derived character states in most characters studied, and a concentrated changes test revealed that some plumage characters evolved in association with habitat type. For example, there was a statistically significant association between loss of dorsal barring and use of densely vegetated habitats among Picoides species. Two analyses indicated that convergence, as opposed to parallel evolution or shared …

Flexible Social Structure Of A Desert Rodent, Rhombomys Opimus: Philopatry, Kinship, And Ecological Constraints, Jan Randall, Konstantin Rogovin, Patricia Parker, John Eimes

Biology Department Faculty Works

We tested hypotheses based on philopatry, kinship, and ecological constraints to explain sociality in a semifossorial desert rodent, the great gerbil, Rhombomys opimus. Data were collected in the field in Uzbekistan in the spring and fall of 1996 and 1998–2004. Population densities fluctuated dramatically with high turnover in both males and females to reveal that dispersal and social structure were density dependent. Fewer gerbils dispersed at higher densities and members of family groups dispersed together. A majority of females lived in groups at high densities, but as population densities declined, proportionally more females were solitary. DNA analysis revealed that group-living …

Bateman Gradients In Field And Laboratory Studies: A Cautionary Tale, Patricia Parker, Zuleyma Tang-Martinez

Biology Department Faculty Works

Since tools of molecular genetics became readily available, our understanding of bird mating systems has undergone a revolution. The majority of passerine species investigated are socially monogamous, but have been shown to be genetically polygamous. Data sets from natural populations of juncos suggest that multiple mating by females results in a sexual selection gradient as steep for females as for males (a result that does not support Bateman's predictions). However, in males, fitness is enhanced directly through fertilization success with multiple matings; in females fitness benefits may be enhanced immediately through direct access to food, protection against predators, or other …