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Biological Sciences Faculty Publications

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Articles 1171 - 1200 of 1571

Full-Text Articles in Life Sciences

Mechanical Properties Of The Integument Of The Common Gartersnake, Thamnophis Sirtalis (Serpentes: Colubridae), Gabriel Rivera, Alan H. Savitzky, Jeffrey A. Hinkley Jan 2005

Mechanical Properties Of The Integument Of The Common Gartersnake, Thamnophis Sirtalis (Serpentes: Colubridae), Gabriel Rivera, Alan H. Savitzky, Jeffrey A. Hinkley

Biological Sciences Faculty Publications

The evolution of the ophidian feeding mechanism has involved substantial morphological restructuring associated with the ability to ingest relatively large prey. Previous studies examining the morphological consequences of macrophagy have concentrated on modifications of the skull and cephalic musculature. Although it is evident that macrophagy requires highly compliant skin, the mechanical properties of the ophidian integument have received limited attention, particularly in the context of feeding. We examined mechanical properties of skin along the body axis in Thamnophis sirtalis (Colubridae). Data were collected from tensile tests and were analyzed using a multivariate analysis of variance (MANOVA) and post-hoc multiple comparison …

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3,4-Methylenedioxymethamphetamine Activates Nuclear Factor- Κb, Increases Intracellular Calcium, And Modulates Gene Transcription In Rat Heart Cells, David A. Tiangco, Frank A. Lattanzio Jr., Christopher J. Osgood, Stephen J. Beebe, Julie A. Kerry, Barbara Y. Hargrave Jan 2005

3,4-Methylenedioxymethamphetamine Activates Nuclear Factor- Κb, Increases Intracellular Calcium, And Modulates Gene Transcription In Rat Heart Cells, David A. Tiangco, Frank A. Lattanzio Jr., Christopher J. Osgood, Stephen J. Beebe, Julie A. Kerry, Barbara Y. Hargrave

Biological Sciences Faculty Publications

3,4-Methylenedioxymethamphetamine (MDMA) is an illicit psychoactive drug that has gained immense popularity among teenagers and young adults. The cardiovascular toxicological consequences of abusing this compound have not been fully characterized. The present study utilized a transient transfection/dual luciferase genetic reporter assay, fluorescence confocal microscopy, and gene expression macroarray technology to determine nuclear factor-κB (NF-κB) activity, intracellular calcium balance, mitochondrial depolarization, and gene transcription profiles, respectively, in cultured rat striated cardiac myocytes (H9c2) exposed to MDMA. At concentrations of 1×10−3 M and 1×10−2 M, MDMA significantly enhanced NF-κB reporter activity compared with 0 M (medium only) control. This …

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A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine Jan 2005

A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine

Biological Sciences Faculty Publications

The black-legged tick Ixodes scapularis linnaeus (Acari: Ixodidae) is an important vector of microbial pathogens. Knowledge of the tick's innate immune response, particularly defensin and other antimicrobial peptides, is important for understanding how microbes survive in this tick. A defensin gene (slnA) from I. scapularis was obtained by reverse transcription-polymerase chain reaction (RT-PCR) using mRNA extracted from tissues of female ticks. RT-PCR indicated the gene was expressed in the midgut, haemocytes, and fat-body, although no evidence of a peptide was found. Sequencing a cloned cDNA fragment revealed a 225 bp open reading frame encoding a 74 amino acid pre-prodefensin, including …

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Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Usa, Harold G. Marshall, Lubomira Burchardt Jan 2005

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Usa, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …

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In Vivo Role Of 20-Hydroxyecdysone In The Regulation Of The Vitellogenin Mrna And Egg Development In The American Dog Tick, Dermacentor Variabilis (Say), Deborah M. Thompson, Sayed M.S. Khalil, Laura A. Jeffers, Usha Ananthapadadmanaban, Daniel E. Sonenshine, Robert D. Mitchell, Christopher J. Osgood, Charles S. Apperson, R. Michael Roe Jan 2005

In Vivo Role Of 20-Hydroxyecdysone In The Regulation Of The Vitellogenin Mrna And Egg Development In The American Dog Tick, Dermacentor Variabilis (Say), Deborah M. Thompson, Sayed M.S. Khalil, Laura A. Jeffers, Usha Ananthapadadmanaban, Daniel E. Sonenshine, Robert D. Mitchell, Christopher J. Osgood, Charles S. Apperson, R. Michael Roe

Biological Sciences Faculty Publications

Injection of the hormone 20-hydroxyecdysone (20-E) into partially fed (virgin) female adults of the American dog tick, Dermacentor variabilis, while they are attached and feeding on the rabbit host, initiated the expression of the vitellogenin (Vg) gene, and Vg protein secretion and uptake by the ovary. The induction of egg production by 20-E in this bioassay was dose dependent in the range of 1-50 times the concentration normally found in a replete, vitellogenic female. Ticks examined 4d after the 50x treatment were still attached to the host, had numerous enlarged vitellin-filled (brown) oocytes in their ovaries, but had not …

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Benthic Fisheries Ecology In A Changing Environment: Unraveling Process To Achieve Prediction, Mark J. Butler Iv Jan 2005

Benthic Fisheries Ecology In A Changing Environment: Unraveling Process To Achieve Prediction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Marine fisheries and the ecosystems that sustain them are increasingly beset by environmental deterioration, and the problem is particularly acute in coastal zones where human Populations are increasing. In the best of circumstances, fishery managers are faced with the multiple, often conflicting, demands of resource users, politicians, and scientists when considering strategies for resource management. A further challenge is that management decisions must be made against a backdrop of a deteriorating environment and the shifting status of coastal ecosystem integrity. Traditional tools for single-species management may be inadequate in these settings. Furthermore. the necessary empirical data to appropriately parameterize models …

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The Architecture Of A Proteomic Network In The Yeast, Emad Ramadan, Christopher Osgood, Alex Pothern Jan 2005

The Architecture Of A Proteomic Network In The Yeast, Emad Ramadan, Christopher Osgood, Alex Pothern

Biological Sciences Faculty Publications

We describe an approach to clustering the yeast protein-protein inter-action network in order to identify functional modules, groups of proteins forming multi-protein complexes accomplishing various functions in the cell. We have developed a clustering method that accounts for the small-world nature of the network. The algorithm makes use of the concept of k-cores in a graph, and employs recursive spectral clustering to compute the functional modules. The computed clusters are annotated using their protein memberships into known multi-protein complexes in the yeast. We also dissect the protein interaction network into a global subnetwork of hub proteins (connected to several clusters), …

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Comparison Of Phytoplankton And Autotrophic Picoplankton Populations Over A 24-Hour Period From A Pond's Surface And Subsurface Waters, Harold G. Marshall, Lubomira Burchardt, Elżbieta Wilk-Woźniak Jan 2005

Comparison Of Phytoplankton And Autotrophic Picoplankton Populations Over A 24-Hour Period From A Pond's Surface And Subsurface Waters, Harold G. Marshall, Lubomira Burchardt, Elżbieta Wilk-Woźniak

Biological Sciences Faculty Publications

Phytoplankton abundance and composition relationships within the surface layer changed over short time periods (4-6 hours) in comparison with more constant associations at 2 cm below the surface. Both strata had a diverse algal flora (>50 taxa), but no distinct neuston assemblage characterized the surface layer algal composition over the 24-hour study. The similarity between the two strata indicated the floral composition of the surface layer came from the water column algae below the surface. Chlorophytes, diatoms, cyanobacteria, and cryptophytes represented the most abundant algal categories for both strata with a total mean phytoplankton abundance of 3,566 cells ml …

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Effects Of Human Disturbances On The Behavior Of Wintering Ducks, Melissa L. Pease, Robert K. Rose, Mark J. Butler Jan 2005

Effects Of Human Disturbances On The Behavior Of Wintering Ducks, Melissa L. Pease, Robert K. Rose, Mark J. Butler

Biological Sciences Faculty Publications

Human activity causes wintering waterfowl to expend energy to avoid humans at a time in their annual cycle when energy conservation is important to survival, migration, and breeding reserves. Understanding the effects of recreational activities on waterfowl is important to managing natural resource areas where migratory birds depend on wetland habitat for resting and feeding. We investigated responses of 7 species of dabbling ducks to 5 different experimental human activities, (a pedestrian, a bicyclist, a truck traveling at 2 different speeds, and an electric passenger tram). Responses of ducks depended on type of disturbance, species, and distance from disturbances. Most …

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A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture Jan 2005

A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture

Biological Sciences Faculty Publications

Based on a continuous 20-year data base ofmonthly sampling in Chesapeake Bay and tidal regions of its major tributaries, 1454 phytoplankton taxa have been identified in these waters. They represent a diverse assemblage of species with a dominant diatom flora throughout the year, in addition to large seasonal representation by chlorophytes, cyanobacteria, cryptophytes and dinoflagellates. Included among this flora were 34 potential harmful or toxin producing species. The phytoplankton compositions associated with the seasonal successional patterns are discussed, in addition to characterizing the dominant floral relationships, with comparison to early composition records within the Bay. Several of the present day …

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Feeding Ecology Of Juvenile Spiny Lobster, Panulirus Interruptus, On The Pacific Coast Of Baja California Sur, Mexico, Verónica Castañeda‐Fernández‐De‐Lara, Elisa Serviere‐Zaragoza, Sergio Hernández‐Vázquez, Mark J. Butler Iv Jan 2005

Feeding Ecology Of Juvenile Spiny Lobster, Panulirus Interruptus, On The Pacific Coast Of Baja California Sur, Mexico, Verónica Castañeda‐Fernández‐De‐Lara, Elisa Serviere‐Zaragoza, Sergio Hernández‐Vázquez, Mark J. Butler Iv

Biological Sciences Faculty Publications

Many aspects of the early life history of the red lobster Panulirus interruptus are little known, including the relationship between habitat structure, food resource availability, and nutrition of juveniles. We investigated the spatial and temporal differences in food intake, diet composition, and nutritional condition of juveniles at two sites along the Pacific coast of the Baja California Peninsula (Mexico) with contrasting oceanographic and biological conditions. One site (Arvin) is located inside a protected bay, Bahia Tortugas, where the waters are cooler and temperate seagrasses and macroalgae are the dominant benthic flora. The second site (Queen) in Bahia Sebastian Vizcaino was …

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New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe Jan 2005

New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe

Biological Sciences Faculty Publications

Three new species of Tegano are described, two from caves on Panglao Island, Bohol, Philippines, and one from a cave on Peleliu Island, Palau. Sriha vagabunda from Sri Lanka is reassigned to the genus Tegano based primarily on the high degree of similarity between Sriha vagabunda and species of Tegano and the fact that these species exhibit a great deal of variation in the reduction of the mandibular palp. A new species of Melita with characters intermediate between those defining the genera Abludomelita, Melita, and Paraniphargus is described from a spring on Guam. The characters of the new …

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Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd Jan 2005

Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd

Biological Sciences Faculty Publications

No abstract provided.

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Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose Jan 2005

Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose

Biological Sciences Faculty Publications

Oryzomys palustris (marsh rice rat) and Microtus pennsylvanicus (meadow vole) cohabit coastal marshes in the mid-Atlantic US. Both were live-trapped for 23 months at two tidal marsh sites in Virginia to assess their demography near the margins of their distributions. In the presence of dense vegetation, population dynamics of the two species were seasonal and positively correlated, with densities declining through the winter. At the more sparsely vegetated site, densities of both species were lower, and densities of M. pennsylvanicus were negatively correlated with those of O. palustris. Patterns of reproduction differed between the species. O. palustris was reproductively …

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Soil Biota Facilitate Exotic Acer Invasions In Europe And North America, Kurt O. Reinhart, Ragan M. Callaway Dec 2004

Soil Biota Facilitate Exotic Acer Invasions In Europe And North America, Kurt O. Reinhart, Ragan M. Callaway

Biological Sciences Faculty Publications

The primary hypothesis for successful exotic plant invasions is that the invaders have escaped the specialist consumers that control them (Enemy Release Hypothesis). However, few studies have rigorously tested this assertion with biogeographical experiments or considered the effects of soil organisms. We tested the Enemy Release Hypothesis and the enhanced role of mutualisms by comparing density patterns of the North American Acer negundo and European A. platanoides trees in their native and nonnative ranges. Invaders that have escaped their natural enemies are predicted to attain greater densities in nonnative than native ranges. To determine whether interactions with soil biota could …

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Loss Of Enemy Resistance Among Introduced Populations Of St. John's Wort (Hypericum Perforatum), John L. Maron, Montserrat Vilà, John Arnason Dec 2004

Loss Of Enemy Resistance Among Introduced Populations Of St. John's Wort (Hypericum Perforatum), John L. Maron, Montserrat Vilà, John Arnason

Biological Sciences Faculty Publications

The Evolution of Increased Competitive Ability (EICA) hypothesis predicts that introduced plants should lose enemy resistance and in turn evolve increased size or fecundity. We tested the first prediction of this hypothesis by growing introduced North American and native European genotypes of St. John's Wort (Hypericum perforatum) in common gardens in the state of Washington, USA, and in Girona, Spain. In both gardens we measured levels of hypericin and pseudohypericin (and in Washington, hypericide)— compounds known to be toxic to generalist pathogens and herbivores. In a third common garden, in Spain, we experimentally manipulated native pathogen pressure (by …

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Reconstitution Of Copii Vesicle Fusion To Generate A Pre-Golgi Intermediate Compartment, Dalu Xu, Jesse C. Hay Nov 2004

Reconstitution Of Copii Vesicle Fusion To Generate A Pre-Golgi Intermediate Compartment, Dalu Xu, Jesse C. Hay

Biological Sciences Faculty Publications

What is the first membrane fusion step in the secretory pathway? In mammals, transport vesicles coated with coat complex (COP) II deliver secretary cargo to vesicular tubular clusters (VTCs) that ferry cargo from endoplasmic reticulum exit sites to the Golgi stack. However, the precise origin of VTCs and the membrane fusion step(s) involved have remained experimentally intractable. Here, we document in vitro direct tethering and SNARE-dependent fusion of endoplasmic reticulum-derived COPII transport vesicles to form larger cargo containers. The assembly did not require detectable Golgi membranes, preexisting VTCs, or CON function. Therefore, COPII vesicles appear to contain all of the …

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Evaluating Forensic Dna Evidence: Essential Elements Of A Competent Defense Review, Dan E. Krane Nov 2004

Evaluating Forensic Dna Evidence: Essential Elements Of A Competent Defense Review, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

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The Effects Of Postfire Salvage Logging On Aquatic Ecosystems In The American West, J. R. Karr, Jj Rhodes, Gw Minshall, F. Richard Hauer, R. L. Beschta, C. A. Frissell, D. A. Perry Nov 2004

The Effects Of Postfire Salvage Logging On Aquatic Ecosystems In The American West, J. R. Karr, Jj Rhodes, Gw Minshall, F. Richard Hauer, R. L. Beschta, C. A. Frissell, D. A. Perry

Biological Sciences Faculty Publications

Recent changes in the forest policies, regulations, and laws affecting public lands encourage postfire salvage logging, an activity that all too often delays or prevents recovery. In contrast, the 10 recommendations proposed here can improve the condition of watersheds and aquatic ecosystems.

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Evaluating Forensic Dna Evidence, Dan E. Krane Oct 2004

Evaluating Forensic Dna Evidence, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

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Forensic Dna Evidence: Collection, Mixtures, And Degradation, Dan E. Krane Oct 2004

Forensic Dna Evidence: Collection, Mixtures, And Degradation, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.

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Facultative Altitudinal Movements By Mountain White-Crowned Sparrows (Zonotrichia Leucophrys Oriantha) In The Sierra Nevada, Thomas P. Hahn, Keith W. Sockman, Creagh W. Breuner, Martin L. Morton Oct 2004

Facultative Altitudinal Movements By Mountain White-Crowned Sparrows (Zonotrichia Leucophrys Oriantha) In The Sierra Nevada, Thomas P. Hahn, Keith W. Sockman, Creagh W. Breuner, Martin L. Morton

Biological Sciences Faculty Publications

Mountain White-crowned Sparrows (Zonotrichia leucophrys oriantha) winter in Mexico and often arrive in the vicinity of their breeding grounds in the Sierra Nevada well before nesting is possible. Arrival at Tioga Pass, Califomia (elevation 3,030 m), usually occurs in early May, but residual winter snow and adverse weather can delay nesting for weeks. We used radiotelemetry to determine whether prebreeding Mountain White-crowned Sparrows engaged in weather-related altitudinal movements during the waiting period between the end of spring migration and onset of breeding during 1995-2001, with a range of residual winter snowpacks. Interannual variation in arrival date and onset …

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The Signal Peptide Of The Junín Arenavirus Envelope Glycoprotein Is Myristoylated And Forms An Essential Subunit Of The Mature G1-G2 Complex, Joanne York, Victor Romanowski, Min Lu, Jack H. Nunberg Oct 2004

The Signal Peptide Of The Junín Arenavirus Envelope Glycoprotein Is Myristoylated And Forms An Essential Subunit Of The Mature G1-G2 Complex, Joanne York, Victor Romanowski, Min Lu, Jack H. Nunberg

Biological Sciences Faculty Publications

Arenaviruses comprise a diverse family of rodent-borne viruses that are responsible for recurring and emerging outbreaks of viral hemorrhagic fevers worldwide. The Junin virus, a member of the New World arenaviruses, is endemic to the pampas grasslands of Argentina and is the etiologic agent of Argentine hemorrhagic fever. In this study, we have analyzed the assembly and function of the Junin virus envelope glycoproteins. The mature envelope glycoprotein complex is proteolytically processed from the GP-C precursor polypeptide and consists of three noncovalently associated subunits, G1, G2, and a stable 58-amino-acid signal peptide. This tripartite organization is found both on virions …

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Novel Weapons: Invasive Success And The Evolution Of Increased Competitive Ability, Ragan M. Callaway, Wendy M. Ridenour Oct 2004

Novel Weapons: Invasive Success And The Evolution Of Increased Competitive Ability, Ragan M. Callaway, Wendy M. Ridenour

Biological Sciences Faculty Publications

When introduced to new habitats by humans, some plant species become much more dominant. This is primarily attributed to escape from specialist consumers. Release from these specialist enemies is also thought by some to lead to the evolution of increased competitive ability, driven by a decrease in the plant's resource allocation to consumer defense and an increase in allocation to size or fecundity. Here, we discuss a new theory for invasive success – the “novel weapons hypothesis”. We propose that some invaders transform because they possess novel biochemical weapons that function as unusually powerful allelopathic agents, or as mediators of …

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Determining Rates Of Change And Evaluating Group-Level Resiliency Differences In Hyporheic Microbial Communities In Response To Fluvial Heavy-Metal Deposition, Kevin P. Feris, Philip W. Ramsey, Matthias Rillig, Johnnie N. Moore, James E. Gannon, William E. Holben Aug 2004

Determining Rates Of Change And Evaluating Group-Level Resiliency Differences In Hyporheic Microbial Communities In Response To Fluvial Heavy-Metal Deposition, Kevin P. Feris, Philip W. Ramsey, Matthias Rillig, Johnnie N. Moore, James E. Gannon, William E. Holben

Biological Sciences Faculty Publications

Prior field studies by our group have demonstrated a relationship between fluvial deposition of heavy metals and hyporheic-zone microbial community structure. Here, we determined the rates of change in hyporheic microbial communities in response to heavy-metal contamination and assessed group-level differences in resiliency in response to heavy metals. A controlled laboratory study was performed using 20 flowthrough river mesocosms and a repeated-measurement factorial design. A single hyporheic microbial community was exposed to five different levels of an environmentally relevant metal treatment (0, 4, 8, 16, and 30% sterilized contaminated sediments). Community-level responses were monitored at 1, 2, 4, 8, and …

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High Polymorphism In The K-Casein (Csn3) Gene From Wild And Domestic Caprine Species Revealed By Dna Sequencing, Oliver C. Jann, Eva-Maria Prinzenberg, Gordon Luikart, Ana Caroli, Georg Erhardt Jun 2004

High Polymorphism In The K-Casein (Csn3) Gene From Wild And Domestic Caprine Species Revealed By Dna Sequencing, Oliver C. Jann, Eva-Maria Prinzenberg, Gordon Luikart, Ana Caroli, Georg Erhardt

Biological Sciences Faculty Publications

We assessed polymorphisms in exon IV of the k-casein gene (CSN3) in ten different breeds of domestic goat (Capra hircus) from three continents and in three related wild caprine taxa (Capra ibex, Capra sibirica and Capra aegagrus). Thirty-five DNA samples were sequenced within a 558 bp fragment of exon IV. Nine polymorphic sites were identified in domestic goat, including four new polymorphisms. In addition to four previously described polymorphic positions, a total of 13 polymorphisms allowed the identification of 13 DNA variants, corresponding to 10 protein variants. Because of conflicting nomenclature of these variants, we propose …

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Kinetic Isotope Effects In Ras-Catalyzed Gtp Hydrolysis: Evidence For A Loose Transition State, Xinlin Du, Gavin E. Black, Paolo Lecchi, Fred P. Abramson, Stephen R. Sprang Jun 2004

Kinetic Isotope Effects In Ras-Catalyzed Gtp Hydrolysis: Evidence For A Loose Transition State, Xinlin Du, Gavin E. Black, Paolo Lecchi, Fred P. Abramson, Stephen R. Sprang

Biological Sciences Faculty Publications

A remote labeling method has been developed to determine (18)O kinetic isotope effects (KIEs) in Ras-catalyzed GTP hydrolysis. Substrate mixtures consist of (13)C-depleted GTP and [(18)O,(13)C]GTP that contains (18)O at phosphoryl positions of mechanistic interest and (13)C at all carbon positions of the guanosine moiety. Isotope ratios of the nonvolatile substrates and products are measured by using a chemical reaction interface/isotope ratio mass spectrometer. The isotope effects are 1.0012 (0.0026) in the gamma nonbridge oxygens, 1.0194 (0.0025) in the leaving group oxygens (the beta-gamma oxygen and the two beta nonbridge oxygens), and 1.0105 (0.0016) in the two beta nonbridge oxygens. …

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Cancer. A Bull's Eye For Targeted Lung Cancer Therapy, John D. Minna, Adi F. Gazdar, Stephen R. Sprang, Joachim Herz Jun 2004

Cancer. A Bull's Eye For Targeted Lung Cancer Therapy, John D. Minna, Adi F. Gazdar, Stephen R. Sprang, Joachim Herz

Biological Sciences Faculty Publications

No abstract provided.

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Evolution Of Morphological Integration. I. Functional Units Channel Stress-Induced Variation In Shrew Mandibles, Alexander V. Badyaev, Kerry R. Foresman Jun 2004

Evolution Of Morphological Integration. I. Functional Units Channel Stress-Induced Variation In Shrew Mandibles, Alexander V. Badyaev, Kerry R. Foresman

Biological Sciences Faculty Publications

Stress-induced deviations from normal development are often assumed to be random, yet their accumulation and expression can be influenced by patterns of morphological integration within an organism. We studied within-individual developmental variation ( fluctuating asymmetry) in the mandible of four shrew species raised under normal and extreme environments. Patterns of among-individual variation and fluctuating asymmetry were strongly concordant in traits that were involved in the attachment of the same muscles (i.e., functionally integrated traits), and fluctuating asymmetry was closely integrated among these traits, implying direct developmental interactions among traits involved in the same function. Stress-induced variation was largely confined to …

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Uncoupling Conformational Change From Gtp Hydrolysis In A Heterotrimeric G Protein Alpha-Subunit, Celestine J. Thomas, Xinlin Du, Pilong Li, Ying Wang, Elliott M. Ross, Stephen R. Sprang May 2004

Uncoupling Conformational Change From Gtp Hydrolysis In A Heterotrimeric G Protein Alpha-Subunit, Celestine J. Thomas, Xinlin Du, Pilong Li, Ying Wang, Elliott M. Ross, Stephen R. Sprang

Biological Sciences Faculty Publications

Heterotrimeric G protein alpha (G alpha) subunits possess intrinsic GTPase activity that leads to functional deactivation with a rate constant of approximately 2 min(-1) at 30 degrees C. GTP hydrolysis causes conformational changes in three regions of G alpha, including Switch I and Switch II. Mutation of G202-->A in Switch II of G alpha(i1) accelerates the rates of both GTP hydrolysis and conformational change, which is measured by the loss of fluorescence from Trp-211 in Switch II. Mutation of K180-->P in Switch I increases the rate of conformational change but decreases the GTPase rate, which causes transient but …

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