Biology Commons^™

Sources And Diagenetic Alteration Of Organic Matter In Coastal Waters At The Vicinity Of Dar Es Salaam, Tanzania, Ann Muzuka

Tanzania Journal of Science

The stable isotope compositions of organic carbon (OC) and nitrogen, contents of OC and nitrogen, and C/N ratios for four short cores, which were recovered from Msansani Bay (WO 57), off Msimbazi River (WO 76) and Dar es Salaam harbour (WO 62 and WO 74), are used to document temporal variation in the sources and diagenetic alteration of organic matter (OM). The δ15N and δ13C values at sites WO 57, WO 62 and WO 74 show a trend of down-core decrease to the base of the core, and such a down-core trend could be related to diagenetic loss of compounds …

The Occurrence Of Digenean Larvae In Freshwater Snails At Mbezi-Temboni Pond, Dar Es Salaam, Esp Esp Kigadye, G. Nkwengulila

Tanzania Journal of Science

The abundance of digenean larvae in snails at a pond in Mbezi-Temboni, Dar es Salaam, was investigated from July 1996 to June 1997. A total of 2,112 snails belonging to three species, Bulinus globosus Morelet 1866, Bulinus forskalii Ehrenberg 1869, and Melanoides tuberculata Müller 1774 were examined, and 28 (1.3%) were found infected by four species of digenean trematodes. Trematodes were recovered only from Bulinus species; none of the examined M. tuberculata was infected. B. globosus was infected by Schistosoma haematobium Bilharz 1852 (1.14%), unidentified furcocercous cercariae (0.4%), and echinostome cercariae (0.76%). B. forskalii was infected by echinostome cercariae (0.25%) …

Experimental Spat Collecting Of The Edible Oyster, Saccostrea Cucullata Born (Bivalvia) In The Kundichi Creek, Dar Es Salaam, Y. D. Mgaya

Tanzania Journal of Science

A one year study was carried out at Kunduchi Creek, Dar es Salaam, to determine spat settlement using the three different substrates (clutches): coconut shells, asbestos and cockle shells, set at three different depths, 0.5 m, 1 m, and 1.5 m. The experiment was set up at three different sites within the creek. There were no significant differences among treatments (sites, depths, clutches). However, spat settlement exhibited seasonal differences, with peak spatfall recorded during the long rains (April to May). There were significant differences in the number of spat between the upper and lower surfaces of the substrates, with more …

Longitudinal Variation In Muscle Protein Expression And Contraction Kinetics Of Largemouth Bass Axial Muscle, Tierney M. Thys, Jason M. Blank, David J. Coughlin, Fred Schachat

Biological Sciences

The present study investigates muscle protein expression in largemouth bass Micropterus salmoides through intra- and intermyomeric comparisons of white muscle. Using denaturing SDS-polyacrylamide gel electrophoresis, muscle protein expression in the arm and cone regions of sequential myomeres was compared for three bass. Low percentage (4.75 %) polyacrylamide-SDS gels and cyanogen bromide (CNBr) peptide mapping revealed no obvious intramyomeric differences between the myosin heavy chains of the arm and cone regions. Electrophoresis of myofibrils and muscle homogenates on higher percentage gels also failed to demonstrate any significant differences between arm and cone regions in either the myosin light chains or any …

Microscale Patchiness Of Bacterioplankton Assemblage Richness In Seawater, Richard A. Long, Farooq Azam

Faculty Publications

We sought to test the hypothesis that bacterial species richness and composition vary at the millimeter scale in the marine pelagic environment, in response to the heterogeneous distribution of organic matter. To test this hypothesis, it was necessary to design and test a protocol to sample, lyse and analyze (by polymerase chain reaction/denaturing gradient gel electrophoresis [PCR-DGGE]) bacterioplankton species richness in a single microliter of seawater. Significant variation in bacterial species richness was found amongst 1 μl samples. Greater species richness was seen when seawater was enriched with diatom detritus. Examination of species richness at 2 mm intervals over a …

Mf-Ea-705Α & Mf-Ea-705Β, New Metabolites From Microbial Fermentation Of A Streptomyces Sp., Asfia Qureshi, Jacob B. Mauger, Raul J. Cano, Jorge L. Galazzo, May D. Lee

Biological Sciences

No abstract provided.

Effects Of Artisanal Fishing On Marine Communities In The Galápagos Islands, Benjamin I. Ruttenberg

Biological Sciences

The Galápagos Islands harbor some of the least impacted marine ecosystems in the tropics, but there are indications that local artisanal fishing is affecting exploited marine communities. To quantify these effects, I sampled communities of fishes and sea urchins at a number of heavily fished and lightly fished sites throughout the central islands of the archipelago. Sites were selected based on information collected as part of a local fisheries monitoring study and standardized across a number of abiotic factors. Abundance and biomass of the primary target species were significantly lower in the heavily fished sites than in the lightly fished …

Percent G+C Profiling Accurately Reveals Diet-Related Differences In The Gastrointestinal Microbial Community Of Broiler Chickens, Juha H. A. Apajalahti, Anu Kettunen, Michael R. Bedford, William E. Holben

Biological Sciences Faculty Publications

Broiler chickens from eight commercial farms in Southern Finland were analyzed for the structure of their gastrointestinal microbial community by a nonselective DNA-based method, percent G+C-based profiling. The bacteriological impact of the feed source and in-farm whole-wheat amendment of the diet was assessed by percent G+C profiling. Also, a phylogenetic 16S rRNA gene (rDNA)-based study was carried out to aid in interpretation of the percent G+C profiles. This survey showed that most of the 16S rDNA sequences found could not be assigned to any previously known bacterial genus or they represented an unknown species of one of the taxonomically heterogeneous …

Isolation And Characterization Of A Novel As(V)-Reducing Bacterium: Implications For Arsenic Mobilization And The Genus Desulfitobacterium, Allison Niggemyer, Stefan Spring, Erko Stackebrandt, Frank Rosenzweig

Biological Sciences Faculty Publications

Dissimilatory arsenate-reducing bacteria have been implicated in the mobilization of arsenic from arsenic-enriched sediments. An As(V)-reducing bacterium, designated strain GBFH, was isolated from arsenic-contaminated sediments of Lake Coeur d'Alene, Idaho. Strain GBFH couples the oxidation of formate to the reduction of As(V) when formate is supplied as the sole carbon source and electron donor. Additionally, strain GBFH is capable of reducing As(V), Fe(III), Se(VI), Mn(IV) and a variety of oxidized sulfur species. 16S ribosomal DNA sequence comparisons reveal that strain GBFH is closely related to Desulfitobacterium hafniense DCB-2^T and Desulfitobacterium frappieri PCP-1^T. Comparative physiology demonstrates that D …

Predicting Risk To Biodiversity As A Function Of Aquifer Pressure In Gab Mound Springs, A. J. Tyre, Brigitte Tenhumberg, H.P. Possingham

School of Biological Sciences: Faculty Publications

Plants and aquatic invertebrates endemic to mound springs of the Great Artesian Basin (GAB) of Australia are of national biodiversity significance. Springs occur in groups, and current survey data suggest that local extinction and recolonisation within a group does occur naturally. Mound spring fauna are therefore good examples of true metapopulations, and any study of the environmental impacts on these systems must take this into account. Use of GAB water leads to drawdown of the pressure in the aquifer. This can potentially impact mound spring flora and fauna in two ways. First, as pressure decreases, so does flow from spring …

Mammary Gland Cell Death Also Involves Lysosomal Autophagy, Reginald Halaby

Department of Biology Faculty Scholarship and Creative Works

The mammary gland undergoes apoptosis when estrogen ablation occurs, either naturally or enforced. The gland is known to execute the apoptotic process post weaning. Although the involuting mammary gland displays the characteristic biochemical features of apoptosis, including DNA fragmentation, chromatin condensation, and the formation of apoptotic bodies, it also shows evidence of an autophagic death. In this report, apoptosis of the gland was induced by removing the pups from their nursing mothers. In particular, we show that lysosomes increased in size and number, and moved from basal to apical regions in dying rat mammary gland cells. Lysosomal enzyme activities were …

Facilitation And Competition On Gradients In Alpine Plant Communities, Philippe Choler, Richard Michalet, Ragan M. Callaway

Biological Sciences Faculty Publications

We conducted a neighbor removal experiment in natural alpine plant communities of the southwestern Alps to test for the relative importance of competitive and facilitative interactions along elevational and topographical gradients. The experimental sites were chosen to encompass most of the floristic diversity observed along gradients of elevation and topography, which are the two main ecological gradients associated with alpine plant communities in the western Alps. The effects of neighbor removal on the survival, aboveground biomass, and reproduction of five target species were tested at each of six experimental sites. Using biomass data, we calculated relative competitive index (RCI) and …

Mindful Virtue, Mindful Reverence, Ursula Goodenough, Paul Woodruff

Biology Faculty Research

How does one talk about moral thought and moral action as a religious naturalist? We explore this question by considering two human capacities: the capacity for mindfulness, and the capacity for virtue. We suggest that mindfulness is deeply enhanced by an understanding of the scientific worldview and that the four cardinal virtues—courage, fairmindedness, humaneness, and reverence—are rendered coherent by mindful reflection. We focus on the concept of mindful reverence and propose that the mindful reverence elicited by the evolutionary narrative is at the heart of religious naturalism. Religious education, we suggest, entails the cultivation of mindful virtue, in ourselves and …

Iron Acquisition In Rhodococcus Erythrolpolis: The Isolation Of Mutant(S) That Do Not Produce A Siderophore., Jaishree M. Vellore

Electronic Theses and Dissertations

Rhodococcus, a soil bacterium, displays a diverse range of metabolic capabilities with a number of potential practical applications. To exploit the metabolic potential of Rhodococcus, their basic physiology, genetics, and especially the acquisition of essential nutrients like iron, must be understood.

R. erythropolis strain IGTS8 releases a small compound called a siderophore, that scavenges ferric iron from the environment. To learn more about the genetic control of iron acquisition, mutant(s) defective in siderophore production were isolated. Mutants were generated, by inserting a mutagenic plasmid, pJCS506, into the bacterial cell using electroporation. The plasmid, which cannot replicate in these …

Antibiotic Resistance: Multi-Drug Profiles And Genetic Determinants., Lashan Denise Taylor

Electronic Theses and Dissertations

Antimicrobial susceptibility profiles were assembled for isolates of Moraxella catarrhalis collected from the Mountain Home Veteran's Affairs Medical Center (VAMC) clinical laboratory in Johnson City, Tennessee. The goal of the study was to identify isolates for genetic characterization using comparisons of susceptibility profiles. Isolates of Moraxella catarrhalis collected from July 1984 through 1994 were analyzed for β-lactamase production using a Cefinase disk assay.

A multi-drug profile consisting of 11 β-lactam antibiotics was performed on the 41 M. catarrhalis isolates. Kirby Bauer disk assays were performed for 7 cephalosporin and 4 non-cephalosporin antibiotics.

In summary, 2 observations implicate more complex resistance …

Proprioception, Non-Law, And Biolegal History, Owen D. Jones

Vanderbilt Law School Faculty Publications

This Article explores several advantages of incorporating into law various insights from behavioral biology about how and why the brain works as it does. In particular, the Article explores the ways in which those insights can help illuminate the deep structure of human legal systems. That effort is termed "biolegal history."

The Effect Of Thermal Stress On The Mating Behavior Of Three Drosophila Species, Zachary J. Patton, Robert A. Krebs

Biological, Geological, and Environmental Faculty Publications

Selection may act on the weakest link in fitness to change how a species adapts to an environmental stress. For many species, this limitation may be reproduction. After adult Drosophila melanogaster, Drosophila simulans, and Drosophila mojavensis males were exposed to varying levels of thermal stress well below those that endanger life, courtship and mating frequency declined. The regression coefficients of both courtship and mating success did not differ significantly between D. melanogaster and D. simulans males. In contrast, significant differences were present between the two cosmopolitan species and D. mojavensis. Courtship frequency decreased at a much slower rate in D. …

Fisheries Research Report No. 136 - Assessment Of Gonad Staging Systems And Other Methods Used In The Study Of The Reproductive Biology Of Narrow-Barred Spanish Mackerel, Scomberomorus Commerson, In Western Australia, Michael C. Mackie, Paul Lewis

Fisheries Research Reports

Recent research by the Department of Fisheries in Western Australia into the reproductive biology of narrow-barred Spanish mackerel has required the use of various field and laboratory techniques. This report documents the procedures and adaptations of some of these techniques. Assessment and development of illustrated, relevant macroscopic and microscopic staging systems were of particular focus because both have been essential components of the research. The simplified and more reliable macroscopic staging system we developed allowed full use of all gonad samples and a more complete (albeit less distinct) overview of the seasonal pattern of gonad reproductive development. This macroscopic staging …

Re-Evaluating Nadph-Diaphorase Histochemistry As An Indicator Of Nitric Oxide Synthase: An Examination Of The Olfactory System Of Coho Salmon (Oncorhynchus Kisutch), Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

The NADPH-diaphorase (NADPH-d) histochemical technique is commonly used to localize the nitric oxide (NO)-producing enzyme NO synthase (NOS) in neural tissues. In the olfactory tissues of vertebrates, however, NADPH-d staining can be present without the detection of NOS by other methods. We used pharmacological controls to determine whether NADPH-d staining was indicative of NOS in olfactory tissues from coho salmon (Oncorhynchus kisutch). We also compared NADPH-d staining with immunoreactivity to NOS. NADPH-d staining localized to the olfactory epithelium and to the glomerular layer of the olfactory bulb. Two NOS inhibitors, _L-N-nitroarginine and _L-N-methyl-_L-arginine, failed …

Structural And Functional Analysis Of Interhelical Interactions In The Human Immunodeficiency Virus Type 1 Gp41 Envelope Glycoprotein By Alanine-Scanning Mutagenesis, Min Lu, Marisa O. Stoller, Shilong Wang, Jie Liu, Melinda B. Fagan, Jack H. Nunberg

Biological Sciences Faculty Publications

Membrane fusion by human immunodeficiency virus type 1 (HIV-1) is promoted by the refolding of the viral envelope glycoprotein into a fusion-active conformation. The structure of the gp41 ectodomain core in its fusion-active state is a trimer of hairpins in which three antiparallel carboxyl-terminal helices pack into hydrophobic grooves on the surface of an amino-terminal trimeric coiled coil. In an effort to identify amino acid residues in these grooves that are critical for gp41 activation, we have used alanine-scanning mutagenesis to investigate the importance of individual side chains in determining the biophysical properties of the gp41 core and the membrane …

Host-Switching Does Not Circumvent The Ni-Based Defence Of The Ni Hyperaccumulator Streptanthus Polygaloides (Brassicaceae), Micheal A. Davis, Robert S. Boyd, James H. Cane

Faculty Publications

Elevated tissue concentrations of metals have been shown to defend metal-hyperaccumulating plants against both herbivores and pathogens. Tolerance of metal-based defences presents a challenge to herbivores, because heavy metals cannot be degraded or metabolized. One strategy that herbivores can employ to counter high-metal defences is dietary dilution, or host switching. Highly mobile herbivores are most likely to use this strategy, but less mobile lepidopteran larvae can also Improve their performance on toxic hosts if early instar development occurs on more favourable hosts. We examined the effects of host switching on growth and survival of a generalist folivore. Specifically, we tested …

Differential Expression Of Cadherin-2 And Cadherin-4 In The Developing And Adult Zebrafish Visual System, Qin Liu, S. G. Babb, Z. M. Novince, A. L. Doedens, J. Marrs, P. A. Raymond

Biology Faculty Research

Cadherins are homophilic cell adhesion molecules that control development of a variety of tissues and maintenance of adult structures. Although cadherins have been implicated in the development of the brain, including the visual system, in several vertebrate species, little is known of their role in zebrafish. In this study, we examined distribution of cadherin-2 (Cdh2, N-cadherin) in the visual system of developing and adult zebrafish using both immunocytochemical and in situ hybridization methods, and we compared Cdh2 distribution to that of the previously reported and closely related cadherin-4 (Cdh4, R-cadherin). As in other vertebrates, in zebrafish embryos Cdh2 was widely …

Blood-Squirting Variability In Horned Lizards (Phrynosoma), Wade Sherbrooke, George Middendorf, C. Guyer

Department of Biology Faculty Publications

Variability within the genus Phrynosoma in the occurrence of ocular-sinus blood-squirting, reportedly a defense used in canid encounters, is reviewed from the literature. Six species have been reported to squirt blood, and seven species remain unreported. Five of the latter species were tested in dog trials; one exhibited blood-squirting (Phrynosoma hernandesi), one exhibited precursor behaviors but failed to squirt blood (Phrynosoma ditmarsi), and three yielded negative results (Phrynosoma mcallii, Phrynosoma modestum, and Phrynosoma platyrhinos). Instances of blood-squirting in response to human encounters were collected and largely support the negative results for the three species P. mcallii, P. modestum, and P. …

High Frequency Of Extra-Pair Paternity In Eastern Kingbirds, Michael T. Murphy, Diane L. Rowe, Robert C. Fleischer, 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 …

High Frequency Of Extra-Pair Paternity In Eastern Kingbirds, Diane L. Rowe, Michael T. Murphy, Robert C. Fleischer, Paul G. Wolf

Biology Faculty Publications and Presentations

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 …

Mammals Of Fort A. P. Hill, Caroline County, Virginia And Vicinity, A. Scott Bellows, Joseph C. Mitchell, John F. Pagels, Heather N. Mansfield

Virginia Journal of Science

Fort A.P. Hill (APH) is a 30,329 ha military training installation (U.S. Army) located in the upper Coastal Plain of Caroline County, Virginia. It was formed in 1941 and named in honor of Civil War Confederate Lt. General Ambrose Powell Hill. The current landscape includes a mosaic of habitats that range from old fields to hardwood forests. Forty species of mammals are known to exist on or near the installation. These include one marsupial, five insectivores, 9 chiropterans, one lagomorph, 12 rodents, 10 carnivores, and one cervid. We have studied many of the species on APH since 1997. In this …

Cocaine- And Amphetamine-Regulated Transcript Peptide Modulation Of Voltage-Gated Ca2+ Signaling In Hippocampal Neurons, Elena (Olena) Petroff, Jianguo Chen, Pastor R. Couceyro, Toshinori Hoshi

Department of Biology Faculty Scholarship and Creative Works

Administration of cocaine and amphetamine increases cocaine- and amphetamine-regulated transcript (CART) expression in the rat striatum (Douglass et al., 1995). CART mRNA is highly expressed in different parts of the human and rat brain, including hippocampus (Douglass et al., 1995; Couceyro et al., 1997; Kuhar and Yoho, 1999; Hurd and Fagergren, 2000). The presence of CART peptide 55-102 immunoreactivity in dense core vesicles of axon terminals suggests that the peptide may be released and may act as a neuromodulator (Smith et al., 1997) to induce neurophysiological and behavioral effects. Little is known, however, about CART peptide-responsive cells, receptor(s), or intracellular …

Bounce And Double Trill Songs Of Male And Female Western Screech-Owls: Characterization And Usefulness For Classification Of Sex, Brian L. Herting, James R. Belthoff

Biology Faculty Publications and Presentations

Both sexes of adult Western Screech-Owls (Otus kennicottii) sing in response to playback of conspecific song within their territories. Two primary songs are the bounce and double trill. Using sonographic analysis of tape-recorded vocalizations, our study quantified characterstics of bounce and double trill songs uttered by individuals within a population of Western Screech-Owls inhabiting riparian woodlands in southwestern Idaho. We asked if songs of males and females differed and, if so, how accurately could songs be classified by sex. On average, male bounce songs were ∼30% lower in frequency than bounce songs of females, but song duration, note duration, number …

Genetic Locus Required For Antigenic Maturation Of Rhizobium Etli Ce3 Lipopolysaccharide, Dominik M. Duelli, Andrea Tobin, Jodie M. Box, V.S. Kumar Kolli, Russell W. Carlson, K. Dale Noel

Biological Sciences Faculty Research and Publications

Rhizobium etli modifies lipopolysaccharide (LPS) structure in response to environmental signals, such as low pH and anthocyanins. These LPS modifications result in the loss of reactivity with certain monoclonal antibodies. The same antibodies fail to recognize previously isolated R. etli mutant strain CE367, even in the absence of such environmental cues. Chemical analysis of the LPS in strain CE367 demonstrated that it lacked the terminal sugar of the wild-type O antigen, 2,3,4-tri-O-methylfucose. A 3-kb stretch of DNA, designated as lpe3, restored wild-type antigenicity when transferred into CE367. From the sequence of this DNA, five open reading frames …

Whence Meiosis?, Anne M. Villeneuve, Kenneth J. Hillers

Biological Sciences

Sexual reproduction predominates among eukaryotic organisms on our planet. While debate continues over why this should be so, burgeoning genomic and functional information now allows us to begin to think reasonably about some of the events that may have occurred to make sex possible in the first place.