Life Sciences Commons^™

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan Bond, John Stephens, Daniel Pondella, James Allen, Mark Helvey

Alan B. Bond

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …

Reduction Of Fe(Iii), Mn(Iv), And Toxic Metal At 100 Degrees C By Pyrobaculum Islandicum, Kazem Kashefi, Derek Lovley

Derek Lovley

It has recently been noted that a diversity of hyperthermophilic microorganisms have the ability to reduce Fe(III) with hydrogen as the electron donor, but the reduction of Fe(III) or other metals by these organisms has not been previously examined in detail. When Pyrobaculum islandicum was grown at 100 degrees C in a medium with hydrogen as the electron donor and Fe(III)-citrate as the electron acceptor, the increase in cell numbers of P. islandicum per mole of Fe(III) reduced was found to be ca. 10-fold higher than previously reported. Poorly crystalline Fe(III) oxide could also serve as the electron acceptor for …

Access To Another Mind: Naturalistic Theories Require Naturalistic Data, Mark A. Krause, Gordon Burghardt

Gordon Burghardt

If there is to be a natural theory of consciousness that would satisfy both philosophers and scientists, it must be based on naturalistic data and minimal clutter accumulated from semantic arguments. Carruthers offers a 'natural' theory of consciousness that is rather myopic. To explore the evolutionary basis of consciousness, a natural theory should include comparative psychological and neurological data that encompass nonlinguistic measures. Such an approach could provide a clearer picture of the adaptive function, mechanisms, and origins of consciousness.

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Jack Frankel

Protection From Oxidative Stress–Induced Apoptosis In Cortical Neuronal Cultures By Iron Chelators Is Associated With Enhanced Dna Binding Of Hypoxia-Inducible Factor-1 And Atf-1/Creb And Increased Expression Of Glycolytic Enzymes, P21waf1/Cip1, And Erythropoietin, Kevin O'Donovan

Kevin O'Donovan

No abstract provided.

The Egr Family Of Transcription-Regulatory Factors: Progress At The Interface Of Molecular And Systems Neuroscience, Kevin O'Donovan

Kevin O'Donovan

No abstract provided.

Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The objective of this study was the research of novel and inexpensive sources of polysaccharides degrading enzymes such as amylases and glucanases from local plants in order to justify their biotechnological applications. The isolation of two l3-amylases and an endo-1,3-ß-D-glucanase was reached using common protein purification methods such as buffer extraction, ammonium sulfate fractionation, ionexchange and gel filtration chromatographies. The methods used were simple and easily reproducible, suggesting the possibilfty of large-scale production. ln the crude extract of Curculigo pilosa tuber, only ß-amylase was detected as starch degrading enzyme and its activity was approximately 282 Uig of fresh material. The …

New Developments In A Hazard Identification Algorithm For Hormone Receptor Ligands, Steven P. Bradbury, Ovanes Mekenyan, Nina Nikolova, Stoyan Karabunarliev, Gerald T. Ankley, Bjorn Hansen

Steven P. Bradbury

Recently we described the Common REactivity PAttern (COREPA) technique to screen data sets of diverse structures for their ability to serve as ligands for steroid hormone receptors [1]. The approach identi®es and quanti®es similar global and local stereoelectronic characteristics associated with active ligands through a comparison of energeticallyreasonable conformer distributions for selected descriptors. For each stereoelectronic descriptor selected, discrete conformer distributions from a training set of ligands are evaluated and parameter ranges common for conformers from all the chemicals in the training set are identi®ed. The use of discrete partitions of parameter ranges to de®ne common reactivity patterns can, however, …

Recovery And Viability Of Edwardsiella Ictaluri From Great Blue Herons Ardea Herodias Fed E. Ictaluri-Infected Channel Catfish Lctalurus Punctatus Fingerlings, Paul R. Waterstrat, Brian S. Dorr, James F. Glahn, Mark E. Tobin

Brian S Dorr

No abstract provided.

Biotransformation Of 4-Methoxyphenol In Rainbow Trout (Oncorhynchus Mykiss) Hepatic Microsomes, Steven P. Bradbury, R. Kolanczyk, P. Schmieder, T. Spizzo

Steven P. Bradbury

Rainbow trout liver microsomes were used to study the O-demethylation and ring hydroxylation of 4-methoxyphenol (4-MP) (4-hydroxyanisole) at 11 and 25°C by directly measuring the production of the primary metabolite hydroquinone (HQ), 4-methoxycatechol (4-MCAT), and additional metabolites. An HPLC method with integrated ultraviolet (UV) and electrochemical detection (ECD) was developed for metabolite identification and quantification at low concentrations. Sample handling with appropriate buffers, solvents, low temperature and light prevented loss of extremely labile metabolites. Saturation kinetics for the production of HQ via O-demethylation of 4-MP (0.66–40 mM) was never achieved, with substrate solubility being the limiting factor. The linear rate …

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey

Daniel Pondella

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …

Energetics Of Locomotion By The Australian Water Rat (Hydromys Chrysogaster): A Comparison Of Swimming And Running In A Semi-Aquatic Mammal, Frank E. Fish, R V. Baudinette

Frank E. Fish

Semi-aquatic mammals occupy a precarious evolutionary position, having to function in both aquatic and terrestrial environments without specializing in locomotor performance in either environment. To examine possible energetic constraints on semi-aquatic mammals, we compared rates of oxygen consumption for the Australian water rat (Hydromys chrysogaster) using different locomotor behaviors: swimming and running. Aquatic locomotion was investigated as animals swam in a water flume at several speeds, whereas water rats were run on a treadmill to measure metabolic effort during terrestrial locomotion. Water rats swam at the surface using alternate pelvic paddling and locomoted on the treadmill using gaits that included …

Genome-Wide Bioinformatic And Molecular Analysis Of Introns In Saccharomyces Cerevisiae, Marc Spingola, Leslie Grate, David Haussler, Manuel Ares

Marc Spingola

Attitudes And Perceptions About Ecological Resources And Hazards Of People Living Around The Savannah River Site, Joanna Burger, Jessica Sanchez, J. Whitfield Gibbons, Jeanine Ondrof, Robert Ramos, Michael J. Mcmahon, Karen F. Gaines, Christine Lord, Marie Fullmer, Michael Gochfeld

Karen F. Gaines

Although considerable attention is devoted to environmental monitoring and assessment with respect to both pollutants and the status of particular plant or animal populations, less attention is devoted to assessing people's attitudes about the relative importance of ecological resources. In this paper we examine the attitudes and perceptions about ecological resources of people living around the Department of Energy's Savannah River Site (SRS), in South Carolina. Our overall hypothesis is that people who are directly affected by the possible outcomes and consequences of a particular hazard (i.e., those people employed at SRS) will undervalue the risks and overvalue the potential …

Epistasis, Henry R. Owen

Henry R. Owen

No abstract provided.

Adapt Globally, Act Locally: The Effect Of Selective Sweeps On Bacterial Sequence Diversity, J. Majewski, Frederick Cohan

Frederick M. Cohan

No abstract provided.

Revegetating Desert Plant Communities, David A. Bainbridge

David A Bainbridge

Desert revegetation is possible but not easy. Careful attention to plant production (root:shoot), site prep, planting, irrigation and aftercare can lead to good survival even under extreme desert conditions. Cost per survivor is a critical consideration.

Soil Pitting For Revegetation, David A. Bainbridge

David A Bainbridge

Soil pitting provides many benefits in ecological restoration of degraded lands. The pits capture rainwater, trap seeds and soil symbionts and protect seedlings from windblast.

Structural, Functional And Biochemical Responses Of Datura Innoxia Mill. To Coal-Smoke Pollution, Azamal Husen, Muhammad Iqbal

Dr. Azamal Husen

Effect of coal-smoke pollution on Datura innoxia Mill. was investigated. D. innoxia has shown that leaf length, single leaf area, total leaf area and leaves per plant decreased but leaf biomass increased under pollution stress. Epidermal features of upper and lower leaf surface responded to pollution stress differently. Rate of photosynthesis and stomatal conductance were low, internal CO2 concentration was high and levels of chlorophyll a and b, total chlorophyll and carotenoids were reduced in polluted condition. Levels of proteins, reducing sugar in roots and sulphur contents in leaves, stem, roots and seeds showed significant increase under the polluted condition. …

A Comparison Of Three Methods For Determining Root-Knot Nematode Infection Of Cotton Roots, Robert G. Mcbride, Robert Mikkelsen

Robert Mikkelsen

Three methods for determining the extent of infection of cotton roots (Gossypium hirsutum L.) by root-knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, were compared. Root-knot nematode eggs were added to pots containing either sterilized soil or soil amended with rye, and cotton seedlings were planted. Cotton root systems were then assessed for infection/damage after 14 and 28 days of exposure. At the 14-day sampling, the roots were stained, using the lactophenol acid fuchsin method and the juvenile nematodes counted. At the 28-day samplings, the cotton roots were given a visual rating for nematode-induced root galling (0-100), and the galls …

Soil Amino Acid Utilization Among Species Of The Cyperaceae: Plant And Soil Processes, Ted K. Raab, David A. Lipson, Steven K. Scmidt, Russ K. Monson

Ted K. Raab

Amino acids are released during the decomposition of soil organic matter and have been shown to be utilized as a nitrogen source by some non-mycorrhizal species in the family Cyperaceae (the sedge family). Twelve out of 13 Cyperaceae species examined in the current study were capable of absorbing soil amino acids in the non-mycorrhizal state. With two exceptions (two species in the genus Kobresia), species from subalpine or alpine habitats exhibited lower rates of total nitrogen uptake compared to species from more temperate habitats, which is possibly explained by lower growth rates in the alpine and subalpine species and a …

Variation In Competitive Abilities Of Plants And Microbes For Specific Amino Acids, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson

Ted K. Raab

Microbes are assumed to possess strong competitive advantages over plants for uptake of nutrients from the soil. The finding that non-mycorrhizal plants can obtain a significant fraction of their N requirement from soil amino acids contradicts this assumption. The amino acid glycine (Gly) has been used as a model amino acid in many recent studies. Our preliminary studies showed that Gly was a poor substrate for microbial growth compared to other amino acids. We tested the hypothesis that the alpine sedge Kobresia myosuroides competes better for Gly than for other amino acids because of decreased microbial demand for this compound. …

The Effect Of Water Level Management On The Soils And Vegetation Of Two Coastal Louisiana Marshes, Brian J. Wilsey, K. M. Flynn, I. A. Mendelssohn

Brian J. Wilsey

Wetland degradation and loss is the result of a combination of natural causes and anthropogenic activities and is a serious problem in coastal Louisiana, where approximately 80% of the total US coastal wetland loss since the 1930’s has occurred. One method currently used to address this wetland loss problem is structural marsh management,which is the use of levees and water control structures to control hydroperiod. The effects of structural marsh management on two managed marshes in Southern Louisiana (Unit 4 of the Rockefeller Wildlife Refuge and the Fina LaTerre Mitigation Bank) were evaluated by comparing the soils and the dominant …

Temporal Changes In Purity And Specific Activity Of Tritium-Labeled 2,3,7,8-Tetrachlorodibenzo-Ρ-Dioxin: Radiopurity Model For Toxicology, Steven P. Bradbury, Joseph D. Fernandez, Philip M. Cook, Brian C. Butterworth

Steven P. Bradbury

The specific activity (S) and radiopurity (R) of tritium labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin, [3H]TCDD, were measured by gas chromatography/mass spectrometry (GC/ MS) while attempting to accurately characterize TCDD doses received by invertebrates, fish, and fish embryos during several toxicology studies conducted over a 3 year period. The [3H]TCDD sample was found to consist of six TCDD analogues involving hydrogen, deuterium, and tritium substitution at the 1,6-dibenzo-p-dioxin carbon positions and a complex mixture of impurities (with and without tritium labels). Planar aromatic impurities were identified as tolyl- TCDD adducts and appeared to result from the decay of 3H radiolabels to produce TCDD carbocations …

Derivation Of Wildlife Values For Mercury, Steven P. Bradbury, John Nichols, Jeff Swartout

Steven P. Bradbury

A procedure has been developed to estimate surface water concentrations of toxicants (“wildlife values”) that will protect the viability of wildlife populations associated with aquatic resources. This procedure was designed primarily to protect piscivorous birds and mammals from compounds that bioaccumulate in fish and was used in the Great Lakes Water Quality Initiative (GLI) to calculate wildlife values (WV) for mercury, DDT/DDE, total polychlorinated biphenyls (PCBs), and 2,3,7,8-tetrachlorodibenzodioxin (TCDD). Published in 1995, and expressed as total mercury in unfiltered water, the final wildlife value (WVf) for mercury derived in the GLI was 1300 pg Hg/L. This value was selected as …

New Testing Apparatus For Assessing Interactive Effects Of Suspended Solids And Chemical Stressors On Plankton Invertebrates, Steven P. Bradbury, Carl Herbrandson, Deborah L. Swackhamer

Steven P. Bradbury

To better predict and interpret the responses of aquatic organisms to environmentally relevant chemical exposures, it is necessary to investigate the combined effects of physical (e.g., suspended solids) and chemical stressors. One of the limitations in investigating suspended solids–chemical interactions has been the lack of an appropriate testing system. The specific objective of the current study was to develop and assess a suspended solids testing apparatus (SSTA) for studies on the combined effects of suspended solids and chemicals on aquatic invertebrates. The SSTA was designed to permit the assessment of varying suspended solids concentrations on Daphnia magna at a constant …

The Historical Development Of Agriculture In Illinois, Pamela Riney-Kehrberg

Pamela Riney-Kehrberg

Illinois' agricultural history is long and complex. Illinois' first settlers, the Native Americans, practiced hunting, gathering, and fishing and made use of the resources of the woods and prairies. By the tenth century, Native Americans combined men's hunting with women's agricultural activities to meet the needs of their communities. The earliest crop Native American women cultivated was corn, imported to Illinois from the Southwest.

Regulation Of Growth Anisotropy In Well Watered And Water-Stressed Maize Roots. Ii. Role Of Cortical Microtubules And Cellulose Microfibrils, Tobias Baskin, H.T.H.M Meekes, B.M Liang, R.E. Sharp

Tobias Baskin

We tested the hypothesis that the degree of anisotropic expansion of plant tissues is controlled by the degree of alignment of cortical microtubules or cellulose microfibrils. Previously, for the primary root of maize (Zea mays L.), we quantified spatial profiles of expansion rate in length, radius, and circumference and the degree of growth anisotropy separately for the stele and cortex, as roots became thinner with time from germination or in response to low water potential (B.M. Liang, A.M. Dennings, R.E. Sharp, T.I. Baskin [1997] Plant Physiol 115:101–111). Here, for the same material, we quantified microtubule alignment with indirect immunofluorescence microscopy …

Sensory And Motor Interdependence In Postural Adjustments, Gin Mccollum

Gin McCollum

The sensory reafference from a movement depends upon the movement, and the movement chosen depends upon the available senses, as demonstrated by vestibular patients who abandon certain movements. Often, one variable is assumed to be dependent whereas the other is independent; however, sensory and motor dynamics in posture are interdependent as conditions upon each other. This paper applies conditional dynamics to characterize the global structure of interdependence between sensory states and motor strategies in fast postural adjustments. The mathematical formalism incorporates rich but disparate experimental, clinical, and theoretical results about sensory and motor control of posture.

The control structures presented …

Diversity And Molecular Evolution Of The Rps2 Resistance Gene In Arabidopsis Thaliana, Ana Lucia Caicedo

Ana Lucia Caicedo

The RPS2 gene in Arabidopsis thaliana governs resistance to strains of the bacterial pathogen, Pseudomonas syringae pv. tomato, that express the avrRpt2 gene. The two loci are involved in a gene-for-gene interaction. Seventeen accessions of A. thaliana were sequenced to explore the diversity present in the coding region of the RPS2 locus. An unusually high level of nucleotide polymorphisms was found (1.26%), with nearly half of the observed polymorphisms resulting in amino acid changes in the RPS2 protein. Seven haplotypes (alleles) were identified and their evolutionary relationships deduced. Several of the alleles conferring resistance were found to be closely related, …