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Potent Immunosuppressive Activities Of Cytomegalovirus-Encoded Interleukin-10, Juliet V. Spencer, Kristen M. Lockridge, Peter A. Barry, Gaofeng Lin, Monica Tsang, Mark E.T. Penfold, Thomas J. Schall Jan 2002

Potent Immunosuppressive Activities Of Cytomegalovirus-Encoded Interleukin-10, Juliet V. Spencer, Kristen M. Lockridge, Peter A. Barry, Gaofeng Lin, Monica Tsang, Mark E.T. Penfold, Thomas J. Schall

Biology Faculty Publications

Cytomegalovirus (CMV) has highly evolved mechanisms for avoiding detection by the host immune system. Recently, in the genomes of human and primate CMV, a novel gene comprising segments of noncontiguous open reading frames was identified and found to have limited predicted homology to endogenous cellular interleukin-10 (IL-10). Here we investigate the biological activities of the CMV IL-10-like gene product and show it to possess potent immunosuppressive properties. Both purified bacterium-derived recombinant CMV IL-10 and CMV IL-10 expressed in supernatants of human cells were found to inhibit proliferation of mitogen-stimulated peripheral blood mononuclear cells (PBMCs), with specific activity comparable to that …


Mineralization Of Clapper Rail Eggshell From A Contaminated Salt Marsh System, Alejandro Rodriguez-Navarro, Karen F. Gaines, Christopher S. Romanek, G. R. Masson Jan 2002

Mineralization Of Clapper Rail Eggshell From A Contaminated Salt Marsh System, Alejandro Rodriguez-Navarro, Karen F. Gaines, Christopher S. Romanek, G. R. Masson

Faculty Research & Creative Activity

The effect of contamination on eggshell mineralization has been studied for clapper rails (Rallus longirostris) inhabiting a contaminated salt marsh in coastal Georgia. To assess the impact of contaminants, the thickness, microstructure (crystal orientation), mineral composition, and chemistry of shell material were analyzed from a contaminated site and a nearby reference site using optical microscopy, X-ray diffraction, inductively coupled plasma mass spectrometry, and gas chromatography with electron capture detector. Eggshells from the contaminated site were generally thinner than those from the reference site. Also, eggshells from the contaminated site were abnormally brittle and contained anomalous microstructural attributes. The combination of …


Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott J. Meiners, Steward T.A. Pickett, Steven N. Handel Jan 2002

Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott J. Meiners, Steward T.A. Pickett, Steven N. Handel

Faculty Research & Creative Activity

Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest–old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m2 plots in a 90 3 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus …


Variation In Nuclear Dna Content Across Environmental Gradients: A Quantile Regression Analysis, Charles A. Knight, David D. Ackerly Jan 2002

Variation In Nuclear Dna Content Across Environmental Gradients: A Quantile Regression Analysis, Charles A. Knight, David D. Ackerly

Biological Sciences

The nuclear DNA content of angiosperms varies by several orders of magnitude. Previous studies suggest that variation in 2C DNA content (i.e. the amount of DNA in G1 phase nuclei, also referred to as the 2C-value) is correlated with environmental factors, but there are conflicting reports in the literature concerning the nature of these relationships. We examined variation in 2C DNA content for 401 species in the ecologically diverse California flora in relation to the mean July maximum temperature, January minimum temperature, and annual precipitation within the geographical ranges of these species. Species with small 2C-values predominate in all environments. …


Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet Jan 2002

Heart Rate And Energy Expenditure Of Incubating Wandering Albatrosses: Basal Levels, Natural Variation, And The Effects Of Human Disturbance, H Weimerskirch, Scott A. Shaffer, G Mabille, J Martin, O Boutard, J-L Rouanet

Faculty Publications, Biological Sciences

We studied the changes in heart rate (HR) associated with metabolic rate of incubating and resting adult wandering albatrosses (Diomedea exulans) on the Crozet Islands. Metabolic rates of resting albatrosses fitted with external HR recorders were measured in a metabolic chamber to calibrate the relationship between HR and oxygen consumption (V̇O2) (V̇O2=0.074×HR+0.019, r2=0.567, P<0.001, where V̇O2 is in ml kg–1 min–1 and HR is in beats min–1). Incubating albatrosses were then fitted with HR recorders to estimate energy expenditure of albatrosses within natural field conditions. We also examined the natural variation in HR and the effects of human disturbance on nesting birds by monitoring the changes in HR. Basal HR was positively related to the mass of the individual. The HR of incubating birds corresponded to a metabolic rate that was 1.5-fold (males) and 1.8-fold (females) lower than basal metabolic rate (BMR) measured in this and a previous study. The difference was probably attributable to birds being stressed while they were held in the metabolic chamber or wearing a mask. Thus, previous measurements of metabolic rate under basal conditions or for incubating wandering albatrosses are likely to be overestimates. Combining the relationship between HR and metabolic rate for both sexes, we estimate that wandering albatrosses expend 147 kJ kg–1 day–1 to incubate their eggs. In addition, the cost of incubation was assumed to vary because (i) HR was higher during the day than at night, and (ii) there was an effect of wind chill (<0°C) on basal HR. The presence of humans in the vicinity of the nest or after a band control was shown to increase HR for extended periods (2–3 h), suggesting that energy expenditure was increased as a result of the disturbance. Lastly, males and females reacted differently to handling in terms of HR response: males reacted more strongly than females before handling, whereas females took longer to recover after being handled.


Are Pileated Woodpeckers Attracted To Red-Cockaded Woodpecker Cavity Trees?, Richard N. Conner, Daniel Saenz, James R. Mccormick Jan 2002

Are Pileated Woodpeckers Attracted To Red-Cockaded Woodpecker Cavity Trees?, Richard N. Conner, Daniel Saenz, James R. Mccormick

Faculty Publications

Pileated Woodpeckers (Dryocopus pileatus) cause damage to Red-cockaded Woodpecker (Picoides borealis) cavity trees in the form of cavity enlargement or other excavations on the surface of the pine tree. However, it is not known whether Pileated Woodpeckers excavate more frequently on Red-cockaded Woodpecker cavity trees than on noncavity trees or how stand structure is related to the frequency of Pileated Woodpecker excavation. Also, it is unclear whether the cavity itself provides the stimulus to Pileated Woodpeckers to excavate or whether the presence of Red-cockaded Woodpeckers and their activities are attracting them. We surveyed all of the …


Prey Handling And Diet Of Louisiana Pine Snakes (Pituophis Ruthveni) And Black Pine Snakes (P. Melanoleucus Lodingi), With Comparisons To Other Selected Colubrid Snakes, D. Craig Rudolph, Shirley J. Burgdorf, Richard N. Conner, Christopher S. Collins, Daniel Saenz, Richard R. Schaefer, Toni Trees, C. Michael Duran, Marc Ealy, John G. Himes Jan 2002

Prey Handling And Diet Of Louisiana Pine Snakes (Pituophis Ruthveni) And Black Pine Snakes (P. Melanoleucus Lodingi), With Comparisons To Other Selected Colubrid Snakes, D. Craig Rudolph, Shirley J. Burgdorf, Richard N. Conner, Christopher S. Collins, Daniel Saenz, Richard R. Schaefer, Toni Trees, C. Michael Duran, Marc Ealy, John G. Himes

Faculty Publications

Diet and prey handling behavior were determined for Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi). Louisiana pine snakes prey heavily on Baird's pocket gophers (Geomys breviceps), with which they are sympatric, and exhibit specialized behaviors that facilitate handling this prey species within the confines of burrow systems. Black pine snakes, which are not sympatric with pocket gophers, did not exhibit these specialized behaviors. For comparative purposes, prey handling of P. sayi sayi and Elaphe obsoleta lindheimeri was also examined.


An Automated Technique For Monitoring Nocturnal Avian Vocalizations., Brent Burt, James B. Johnson, Daniel Saenz, Richard N. Conner Jan 2002

An Automated Technique For Monitoring Nocturnal Avian Vocalizations., Brent Burt, James B. Johnson, Daniel Saenz, Richard N. Conner

Faculty Publications

Using audio recording dataloggers, we collected nocturnal bird vocalizations at different sites within the Davy Crockett National Forest and the Stephen F. Austin Experimental Forest. We detected vocalizations of a variety of nocturnal and diurnal species. This technology is useful for its application to avifauna.


Selective Isolation And Numerical Classification Of Novel Thermophilic Streptomycetes, Nevzat Şahi̇n, Erman Öztürk, Kami̇l Işik, Ergi̇n Kari̇ptaş, Reşi̇t Özkanca Jan 2002

Selective Isolation And Numerical Classification Of Novel Thermophilic Streptomycetes, Nevzat Şahi̇n, Erman Öztürk, Kami̇l Işik, Ergi̇n Kari̇ptaş, Reşi̇t Özkanca

Turkish Journal of Biology

Forty-five thermophilic streptomycetes were isolated from different habitats and examined for 163 unit characters with 8 representative thermophilic type strains, 29 reference strains and 16 randomly selected duplicated organisms for many phenotypic properties. The data were evaluated using the simple matching coefficients (S_{SM}), and clustering achieved using the complete algorithm. It was clearly seen that the high cophenetic correlation, low test error values and high similarity level agreed with the defined numerical taxonomic criteria. The test strains were assigned to four aggregate groups consisting seven major (5-8 strains), nine minor (2-4 strains) and ten single membered clusters. It can be …


Effects Of Ph And Aluminium Ion Concentration On Spore Germination And Growth Of Some Soil Fungi, Şükrü Dursun, Lynne Boddy, Juliet C. Frankland Jan 2002

Effects Of Ph And Aluminium Ion Concentration On Spore Germination And Growth Of Some Soil Fungi, Şükrü Dursun, Lynne Boddy, Juliet C. Frankland

Turkish Journal of Biology

Concentrations of three aluminium compounds significantly affected the mycelial extension of Trichoderma viride with low pH values growing on agar media, and the largest effect was recorded with aluminium chloride. Experiments in this work showed that there were significant relationships between Al concentration and pH in the Al inhibition of fungal activity on agar media. Different effects of aluminium concentration on the mycelial extension rate of eight fungal species inoculated on pH gradient plates were recorded. The spore germination of Phoma exigua and Cladosporium herbarum was reduced by increasing aluminium and acidity, and low pH increased the inhibitory effect of …


Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger Jan 2002

Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger

Faculty Research & Creative Activity

: The fact that raccoons (Procyon lotor) are an opportunistic omnivore has severely complicated interpreta- tions of contaminant uptake patterns due to the inability to determine the trophic position an individual occupies. Moreover, few studies have examined the relationships between heavy metal bioaccumulation and trophic struc- ture, especially in the terrestrial environment. In this study, the stable isotopes of nitrogen were used to charac- terize the feeding habits of the raccoon at the population level and to determine whether metal burden was relat- ed to trophic feeding structure within a welldefined ecosystem. Raccoon populations were isotopically distinct, and significant positive …


Cloning Of Plants, Henry R. Owen Jan 2002

Cloning Of Plants, Henry R. Owen

Faculty Research & Creative Activity

No abstract provided.


Scirpus Ancistrochaetus (Cyperaceae): First Record In Canada, Stuart G. Hay, Gordon C. Tucker Jan 2002

Scirpus Ancistrochaetus (Cyperaceae): First Record In Canada, Stuart G. Hay, Gordon C. Tucker

Faculty Research & Creative Activity

No abstract provided.


Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott Meiners, Steward Pickett, Steven Handel Jan 2002

Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott Meiners, Steward Pickett, Steven Handel

Faculty Research & Creative Activity

Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest–old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m2 plots in a 90 3 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus …


Scirpus Ancistrochaetus (Cyperaceae): First Record In Canada, Stuart Hay, Gordon Tucker Jan 2002

Scirpus Ancistrochaetus (Cyperaceae): First Record In Canada, Stuart Hay, Gordon Tucker

Faculty Research & Creative Activity

No abstract provided.


Two New Species Of Pectis (Asteraceae: Tageteae) From South America, David J. Keil Jan 2002

Two New Species Of Pectis (Asteraceae: Tageteae) From South America, David J. Keil

Biological Sciences

Pectis hassleri and P. pumila are new species, the former from the Gran Chaco area of Paraguay and the latter from southwester Encuador and northwestern Peru. Pectis hassleri differs from P. odorata by leaves that are glandular-punctaoten the adaxial as well as the abaxial surfaces, by longer and wider ligules of the ray florets, and by ray pappi of awns and shorter bristles. Pectis pumila differs from the closely related P. arida by its wider leaves and by its sessile or subsessile capitula with campanulatein volucresa nd obovatep hyllaries.A hexaploid chromosome count of 2n = 361 is newly reported for …


Antimicrobial Activity Of Plants Collected From Serpentine Outcrops In Sri Lanka, Nishanta Rajakaruna, Cory S. Harris, G. H. N. Towers Jan 2002

Antimicrobial Activity Of Plants Collected From Serpentine Outcrops In Sri Lanka, Nishanta Rajakaruna, Cory S. Harris, G. H. N. Towers

Biological Sciences

Thirty-two plant species collected from serpentine (ultramafic) soils in Sri Lanka were screened for antimicrobial properties against three Gram-positive and two Gramnegative bacteria, a non-acid fast bacterium, and the yeast, Candida albicans. Methanol extracts of 29 species belonging to 12 families were active against at least one microorganism. Activity against the Gram-positive and non-acid fast bacteria was common, however, only two taxa, Lantana camara L. (Verbenaceae) and a species of Phyllanthus L. (Euphorbiaceae), were active against the Gram-negative bacterium Pseudomonas aeruginosa. None of the species was active against the other Gram-negative bacterium, Escherichia coli, or C. albicans. Photoactivity was observed …


Modeling An Electrosensory Landscape: Behavioral And Morphological Optimization In Elasmobranch Prey Capture, Brandon R. Brown Jan 2002

Modeling An Electrosensory Landscape: Behavioral And Morphological Optimization In Elasmobranch Prey Capture, Brandon R. Brown

Physics and Astronomy

Most biological sensory systems benefit from multiple sensors. Elasmobranchs (sharks, skates and rays) possess an array of electroreceptive organs that facilitate prey location, mate location and navigation. Here, the perceived electrosensory landscape for an elasmobranch approaching prey is mathematically modeled. The voltages that develop simultaneously in dozens of separate sensing organs are calculated using electrodynamics. These voltages lead directly to firing rate modifications in the primary afferent nerves. The canals connecting the sense organs to an elasmobranch's surface exhibit great variation of location and orientation. Here, the voltages arising in the sense organs are found to depend strongly on the …


Template Boundary Definition In Tetrahymena Telomerase, Cary Lai, Michael C. Miller, Kathleen Collins Jan 2002

Template Boundary Definition In Tetrahymena Telomerase, Cary Lai, Michael C. Miller, Kathleen Collins

Biology Faculty Publications

Telomerase elongates chromosome ends by addition of telomeric DNA repeats. The telomerase ribonucleoprotein can copy only a short template sequence within the telomerase RNA subunit. Here, we identify a region of telomerase RNA that is necessary for both correct 5′ template boundary definition and high affinity telomerase reverse transcriptase (TERT) interaction. We also demonstrate that TERT mutants in the RNA binding domain compromise both 5′ boundary definition and RNA binding. Our results indicate that sequence-specific interaction of a telomerase RNA element with the TERT RNA binding domain, not the active site motifs, defines the template boundary.


Characterization Of The Autotrophic Component In Periphyton Upon Typha Angustifolia Detritus In A Freshwater Wetland, Eric J. Warda Jan 2002

Characterization Of The Autotrophic Component In Periphyton Upon Typha Angustifolia Detritus In A Freshwater Wetland, Eric J. Warda

Master's Theses and Doctoral Dissertations

The autotrophic component of periphyton on Typha angustifolia detritus was characterized in a freshwater wetland during a single growing season. 58 genera of algae and cyanobacteria, representing six divisions, were observed throughout the study period. Although the combined algae-cyanobacteria density from within and outside the Typha stands were significantly affected by both sample date and the combination of date and location, no significant differences occurred in biovolume. Similarly, no clear evidence of successional patterns was observed.

Although few significant interactions were observed, Typha detritus provided a substratum for vast numbers and biomass of periphyton. A combined density for the observed …


Crystallization Of Complex Between Soluble Domains Of Adenylyl Cyclase And Activated Gs Alpha, John J. Tesmer, Roger K. Sunahara, David A. Fancy, Alfred G. Gilman, Stephen R. Sprang Jan 2002

Crystallization Of Complex Between Soluble Domains Of Adenylyl Cyclase And Activated Gs Alpha, John J. Tesmer, Roger K. Sunahara, David A. Fancy, Alfred G. Gilman, Stephen R. Sprang

Biological Sciences Faculty Publications

No abstract provided.


Book Review - The Caddisfly Family Phryganeidae (Trichoptera), John C. Morse Jan 2002

Book Review - The Caddisfly Family Phryganeidae (Trichoptera), John C. Morse

Publications

No abstract provided.


Biomphalaria Glabrata Field Isolate (Bb02) Collected For Construction Of Bac Library, Coen Adema Jan 2002

Biomphalaria Glabrata Field Isolate (Bb02) Collected For Construction Of Bac Library, Coen Adema

Biomphalaria Genome Initiative

No abstract provided.


Reproductive Effort, Offspring Size And Benefit/Cost Ratios In The Classification Of Life Histories, Eric Charnov Jan 2002

Reproductive Effort, Offspring Size And Benefit/Cost Ratios In The Classification Of Life Histories, Eric Charnov

Biology Faculty & Staff Publications

There have been many attempts to document links between reproductive allocation and factors such as adult body size and demography. This paper suggests that among closely related taxa, two dimensionless numbers, each a benefit—cost ratio summarizing reproductive timing, allocation and demography, are invariants and thus are useful to classify life histories. The two numbers are E/α and C·E, where E is average adult life span,α is age-at-first-reproduction and C is average mass (per adult) devoted to reproduction per unit of time, divided by the average adult body mass (m); C is usually called reproductive effort'. Since E−1 is the average …


Specimen Catalog, Part 3, Brian D. Frank Jan 2002

Specimen Catalog, Part 3, Brian D. Frank

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Nest-Site Characteristics Of Burrowing Owls (Athene Cunicularia) In The Snake River Birds Of Prey National Conservation Area, Idaho, And Application To Artificial Burrow Installation, James R. Belthoff, R. Andrew King Jan 2002

Nest-Site Characteristics Of Burrowing Owls (Athene Cunicularia) In The Snake River Birds Of Prey National Conservation Area, Idaho, And Application To Artificial Burrow Installation, James R. Belthoff, R. Andrew King

Biology Faculty Publications and Presentations

Burrowing Owl (Athene cunicularia) populations are declining in many portions of their range, and research and management efforts into stemming declines are underway. One tool with promise is the artificial burrow, which can supplement nesting opportunities and play a role in research, mitigation, translocation, and reintroduction studies. However, few studies directly assess important burrow and surrounding topographic features upon which owls choose sites and then construct and install artificial burrows accordingly. In this study we (1) measure physical, vegetative, and topographic characteristics of Burrowing Owl nest sites in the Snake River Birds of Prey National Conservation Area (SRBPNCA); …


Anti-Predation Does Not Fully Explain Grouping In The Chinese Water Deer (Hydropotes Inermis), Lixing Sun Jan 2002

Anti-Predation Does Not Fully Explain Grouping In The Chinese Water Deer (Hydropotes Inermis), Lixing Sun

Biology Faculty Scholarship

The grouping behavior of the Chinese water deer (Hydropotes inermis) was studied at Poyang Lake National Nature Reserve, Jiangxi, China. I made three predictions to test the hypothesis that grouping is an anti-predatory strategy: (1) group size is negatively related to vegetation cover, (2) animals in groups have more time to feed than solitary animals, and (3) animals spend less time in vigilance when they are in groups than when they are alone. Results showed that group size was largest in the mating season and smallest in the parturition season. Deer tended to form larger groups when they …


Performance Limits Of Labriform Propulsion And Correlates With Fin Shape And Motion, Jeffrey A. Walker Phd, Mark W. Westneat Jan 2002

Performance Limits Of Labriform Propulsion And Correlates With Fin Shape And Motion, Jeffrey A. Walker Phd, Mark W. Westneat

Faculty Publications

Labriform locomotion, which is powered by oscillating the paired pectoral fins, varies along a continuum from rowing the fins back and forth to flapping the fins up and down. It has generally been assumed (i) that flapping is more mechanically efficient than rowing, a hypothesis confirmed by a recent simulation experiment, and (ii) that flapping should be associated with wing-shaped fins while rowing should be associated with paddle-shaped fins, To determine whether these hypotheses and the results of the simulation experiment are consistent with natural variation, we compared the steady swimming performance (critical swimming speed) of four species of labrid …


The Effect Of Cytosine Methylation On The Structure And Geometry Of The Holliday Junction: The Structure Of D(Ccggtacm5 Cgg) At 1.5 Å Resolution, Jeff Vargason, P. Shing Ho Jan 2002

The Effect Of Cytosine Methylation On The Structure And Geometry Of The Holliday Junction: The Structure Of D(Ccggtacm5 Cgg) At 1.5 Å Resolution, Jeff Vargason, P. Shing Ho

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.


Pka Phosphorylation Of Src Mediates Camp's Inhibition Of Cell Growth Via Rap1, John M. Schmitt, Philip J. S. Stork Jan 2002

Pka Phosphorylation Of Src Mediates Camp's Inhibition Of Cell Growth Via Rap1, John M. Schmitt, Philip J. S. Stork

Faculty Publications - Department of Biological & Molecular Science

In fibrolast cells, cAMP antagonizes growth factor activation of ERKs and cell growth via PKA and the small P protein Rap1. We demonstrate here that PKA's activation of Rap1 was mediated by the Rap1 guanine nucleotide exchange factor C3G, the adaptor Crk-L, the scaffold protein Cbl, and the tyrosine kinase Src. Src was required for cAMP activation of Rap1 and the inhibition of ERKs and cell growth. PKA activated Src both in vitro and in vivo by phosphorylation was required for cAMP's activation of Src and Rap1, as well as cAMP's inhibition of ERKs and cell proliferation. This study identifies …