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Full-Text Articles in Life Sciences

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 …


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 …


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 …


Estimating Survival Probabilities Of Unmarked Dependent Young When Detection Is Imperfect, Paul M. Lukacs, Victoria J. Dreitz, Kenneth P. Burnham, Fritz L. Knopf Nov 2004

Estimating Survival Probabilities Of Unmarked Dependent Young When Detection Is Imperfect, Paul M. Lukacs, Victoria J. Dreitz, Kenneth P. Burnham, Fritz L. Knopf

Wildlife Biology Faculty Publications

We present a capture-recapture modeling approach to the estimation of survival probability of dependent chicks when only the attending adult bird is marked. The model requires that the bird's nest is found prior to hatching and that the number of eggs that hatch are counted. Subsequent data are sightings of the marked adult and a count of chicks with the adult. The model allows for imperfect detection of chicks, but the number of chicks can never exceed the number of eggs in the nest (i.e., adults cannot adopt chicks). We use data from radio-tagged adult Mountain Plovers (Charadrius montanus …


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.


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 …


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 …


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 …


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 …


Effects Of Natal Departure And Water Level On Survival Of Juvenile Snail Kites (Rostrhamus Sociabilis) In Florida, Victoria J. Dreitz, Wiley M. Kitchens, Donald L. Deangelis Jul 2004

Effects Of Natal Departure And Water Level On Survival Of Juvenile Snail Kites (Rostrhamus Sociabilis) In Florida, Victoria J. Dreitz, Wiley M. Kitchens, Donald L. Deangelis

Wildlife Biology Faculty Publications

Survival rate from fledging to breeding, or juvenile survival, is an important source of variation in lifetime reproductive success in birds. Therefore, determining the relation-ship between juvenile survival and environmental factors is essential to understanding fitness consequences of reproduction in many populations. With increases in density of individuals and depletion of food resources, quality of most habitats deteriorates during the breeding season. Individuals respond by dispersing in search of food resources. Therefore, to understand the influence of environmental factors on juvenile survival, it is also necessary to know how natal dispersal influences survival of juveniles. We examined effects of various …


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 …


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. …


Emissions From Miombo Woodland And Dambo Grassland Savanna Fires, Parikhit Sinha, Peter V. Hobbs, Robert J. Yokelson, Donald R. Blake, Song Gao, Thomas W. Kirschsetter Jun 2004

Emissions From Miombo Woodland And Dambo Grassland Savanna Fires, Parikhit Sinha, Peter V. Hobbs, Robert J. Yokelson, Donald R. Blake, Song Gao, Thomas W. Kirschsetter

Chemistry and Biochemistry Faculty Publications

[1] Airborne measurements of trace gases and particles over and downwind of two prescribed savanna fires in Zambia are described. The measurements include profiles through the smoke plumes of condensation nucleus concentrations and normalized excess mixing ratios of particles and gases, emission factors for 42 trace gases and seven particulate species, and vertical profiles of ambient conditions. The fires were ignited in plots of miombo woodland savanna, the most prevalent savanna type in southern Africa, and dambo grassland savanna, an important enclave of miombo woodland ecosystems. Emission factors for the two fires are combined with measurements of fuel loading, combustion …


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.


Thickness Dependence Of Magneto-Transport In Cu-Co Granular Thin Films, Jian Qing Wang, Ngocnga Dao, Ham H. Kim, Scott L. Whittenburg Jun 2004

Thickness Dependence Of Magneto-Transport In Cu-Co Granular Thin Films, Jian Qing Wang, Ngocnga Dao, Ham H. Kim, Scott L. Whittenburg

Chemistry and Biochemistry Faculty Publications

This work explores the thickness dependence of magneto-transport properties in granular thin films with different thickness. These results are compared with silver-based film series studied earlier. It was observed that the thickness dependence of the GMReffect was sensitive to the surface chemistry of the films. The extraordinary Hall effect (EHE) in these films was measured and found to be different from the Ag-based system. In the Cu-based system, the EHE is a weak function of film thickness over the range studied. When the variation of the spontaneous magnetization is taken into account the effective EHE has a universal thickness dependence


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 …


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 …


Role Of Hydrophobic Residues In The Central Ectodomain Of Gp41 In Maintaining The Association Between Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Subunits Gp120 And Gp41, Joanne York, Jack H. Nunberg May 2004

Role Of Hydrophobic Residues In The Central Ectodomain Of Gp41 In Maintaining The Association Between Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Subunits Gp120 And Gp41, Joanne York, Jack H. Nunberg

Biological Sciences Faculty Publications

The interaction between the gp120 and gp41 subunits of the human immunodeficiency virus envelope glycoprotein serves to stabilize the virion form of the complex and to transmit receptor-induced conformational changes in gp120 to trigger the membrane fusion activity of gp41. In this study, we used site-directed mutagenesis to identify amino acid residues in the central ectodomain of gp41 that contribute to the stability of the gp120-gp41 association. We identified alanine mutations at six positions, including four tryptophan residues, which result in mutant envelope glycoprotein complexes that fail to retain gp120 on the cell surface. These envelope glycoproteins readily shed their …


Rapid Evolution Of An Invasive Plant, John L. Maron, Montserrat Vilà, Riccardo Bommarco, Sarah Elmendorf, Paul Beardsley May 2004

Rapid Evolution Of An Invasive Plant, John L. Maron, Montserrat Vilà, Riccardo Bommarco, Sarah Elmendorf, Paul Beardsley

Biological Sciences Faculty Publications

Exotic plants often face different conditions from those experienced where they are native. The general issue of how exotics respond to unfamiliar environments within their new range is not well understood. Phenotypic plasticity has historically been seen as the primary mechanism enabling exotics to colonize large, environmentally diverse areas. However, new work indicates that exotics can evolve quickly, suggesting that contemporary evolution may be more important in invasion ecology than previously appreciated. To determine the influence of contemporary evolution, phenotypic plasticity, and founder effects in affecting phenotypic variation among introduced plants, we compared the size, fecundity, and leaf area of …


Avian Life-History Evolution Has An Eminent Past: Does It Have A Bright Future?, Thomas E. Martin Apr 2004

Avian Life-History Evolution Has An Eminent Past: Does It Have A Bright Future?, Thomas E. Martin

Wildlife Biology Faculty Publications

No abstract provided.


Legislative Intent, Science And Special Provisions In Wilderness: A Process For Navigating Statutory Compromises, Alan E. Watson, Michael Patterson, Neal Christensen, Annette Puttkammer, Shannon Meyer Apr 2004

Legislative Intent, Science And Special Provisions In Wilderness: A Process For Navigating Statutory Compromises, Alan E. Watson, Michael Patterson, Neal Christensen, Annette Puttkammer, Shannon Meyer

Forest Management Faculty Publications

In order to manage special provisions in U.S. wilderness, several research products are needed. Minimally, a complete understanding of the legislative intent of the provision, in-depth understanding of the deep meanings held by the particular stakeholder community of interest, and some knowledge about the larger population of interest are needed. In this study of jet boat use on the Salmon River in the Frank Church– River of No Return Wilderness, a combination of qualitative and quantitative methods were used to understand the attachment jet boat users have to the activity and the place.


Soil Fungi Alter Interactions Between The Invader Centaurea Maculosa And North American Natives, Ragan M. Callaway, Giles C. Thelen, Sara Barth, Philip W. Ramsey, James E. Gannon Apr 2004

Soil Fungi Alter Interactions Between The Invader Centaurea Maculosa And North American Natives, Ragan M. Callaway, Giles C. Thelen, Sara Barth, Philip W. Ramsey, James E. Gannon

Biological Sciences Faculty Publications

Soil microbes may affect the way exotic invasive plants interact with native neighbors. We investigated the effects of soil fungi on interactions between the invasive weed Centaurea maculosa (spotted knapweed) and six species native to the intermountain prairies of the northwestern United States. We also compared the effect of C. maculosa on the composition of the soil microbial community to that of the native species. In the field, fungicide (Benomyl) reduced AM mycorrhizal colonization of C. maculosa roots by >80%. Fungicide did not significantly reduce non-AM fungi. When grown alone, the biomass of C. maculosa was not affected by the …


Gc Fractionation Enhances Microbial Community Diversity Assessment And Detection Of Minority Populations Of Bacteria By Denaturing Gradient Gel Electrophoresis, William Holben, Keving P. Feris, Anu Kettunen, Juha H. A. Apajalahti Apr 2004

Gc Fractionation Enhances Microbial Community Diversity Assessment And Detection Of Minority Populations Of Bacteria By Denaturing Gradient Gel Electrophoresis, William Holben, Keving P. Feris, Anu Kettunen, Juha H. A. Apajalahti

Biological Sciences Faculty Publications

Effectively and accurately assessing total microbial community diversity is one of the primary challenges in modern microbial ecology. This is particularly true with regard to the detection and characterization of unculturable populations and those present only in low abundance. We report a novel strategy, GC fractionation combined with denaturing gradient gel electrophoresis (GC-DGGE), which combines mechanistically different community analysis approaches to enhance assessment of microbial community diversity and detection of minority populations of microbes. This approach employs GC fractionation as an initial step to reduce the complexity of the community in each fraction. This reduced complexity facilitates subsequent detection of …


Seasonal Dynamics Of Shallow-Hyporheic-Zone Microbial Community Structure Along A Heavy-Metal Contamination Gradient, Kevin P. Feris, Philip W. Ramsey, Chris Frazar, Matthias Rillig, Johnnie N. Moore, William E. Holben Apr 2004

Seasonal Dynamics Of Shallow-Hyporheic-Zone Microbial Community Structure Along A Heavy-Metal Contamination Gradient, Kevin P. Feris, Philip W. Ramsey, Chris Frazar, Matthias Rillig, Johnnie N. Moore, William E. Holben

Biological Sciences Faculty Publications

Heavy metals contaminate numerous freshwater streams and rivers worldwide. Previous work by this group demonstrated a relationship between the structure of hyporheic microbial communities and the fluvial deposition of heavy metals along a contamination gradient during the fall season. Seasonal variation has been documented in microbial communities in numerous terrestrial and aquatic environments, including the hyporheic zone. The current study was designed to assess whether relationships between hyporheic microbial community structure and heavy-metal contamination vary seasonally by monitoring community structure along a heavy-metal contamination gradient for more than a year. No relationship between total bacterial abundance and heavy metals was …


Heterogeneous Chemistry Involving Methanol In Tropospheric Clouds, A. Tabazadeh, Robert J. Yokelson, H. B. Singh, Peter V. Hobbs, J. H. Crawford, L. T. Iraci Mar 2004

Heterogeneous Chemistry Involving Methanol In Tropospheric Clouds, A. Tabazadeh, Robert J. Yokelson, H. B. Singh, Peter V. Hobbs, J. H. Crawford, L. T. Iraci

Chemistry and Biochemistry Faculty Publications

In this report we analyze airborne measurements to suggest that methanol in biomass burning smoke is lost heterogeneously in clouds. When a smoke plume intersected a cumulus cloud during the SAFARI 2000 field project, the observed methanol gas phase concentration rapidly declined. Current understanding of gas and aqueous phase chemistry cannot explain the loss of methanol documented by these measurements. Two plausible heterogeneous reactions are proposed to explain the observed simultaneous loss and production of methanol and formaldehyde, respectively. If the rapid heterogeneous processing of methanol, seen in a cloud impacted by smoke, occurs in more pristine clouds, it could …


Variation In Sulfide Tolerance Of Photosystem Ii In Phylogenetically Diverse Cyanobacteria From Sulfidic Habitats, Scott R. Miller, Brad M. Bebout Feb 2004

Variation In Sulfide Tolerance Of Photosystem Ii In Phylogenetically Diverse Cyanobacteria From Sulfidic Habitats, Scott R. Miller, Brad M. Bebout

Biological Sciences Faculty Publications

Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains …


Comprehensive Laboratory Measurements Of Biomass-Burning Emissions: 2. First Intercomparison Of Open-Path Ftir, Ptr-Ms, And Gc-Ms/Fid/Ecd, Ted J. Christian, B. Kleiss, Robert J. Yokelson, R. Holzinger, P. J. Crutzen, Wein Min Hao, T. Shirai, Donald R. Blake Jan 2004

Comprehensive Laboratory Measurements Of Biomass-Burning Emissions: 2. First Intercomparison Of Open-Path Ftir, Ptr-Ms, And Gc-Ms/Fid/Ecd, Ted J. Christian, B. Kleiss, Robert J. Yokelson, R. Holzinger, P. J. Crutzen, Wein Min Hao, T. Shirai, Donald R. Blake

Chemistry and Biochemistry Faculty Publications

No abstract provided.


El Niño-Southern Oscillation-Induced Variability In Terrestrial Carbon Cycling, Hirofumi Hashimoto, Ramakrishna R. Nemani, Michael A. White, William M. Jolly, Steve C. Piper, Charles D. Keeling, Ranga B. Myneni, Steven W. Running Jan 2004

El Niño-Southern Oscillation-Induced Variability In Terrestrial Carbon Cycling, Hirofumi Hashimoto, Ramakrishna R. Nemani, Michael A. White, William M. Jolly, Steve C. Piper, Charles D. Keeling, Ranga B. Myneni, Steven W. Running

Ecosystem and Conservation Sciences Faculty Publications

We examined the response of terrestrial carbon fluxes to climate variability induced by the El Niño–Southern Oscillation (ENSO). We estimated global net primary production (NPP) from 1982 to 1999 using a light use efficiency model driven by satellite-derived canopy parameters from the Advanced Very High Resolution Radiometer and climate data from the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis project. We estimated a summed heterotrophic respiration and fire carbon flux as the residual between NPP and the terrestrial net carbon flux inferred from an atmospheric inversion model, excluding the impacts of land use change. We propose that …


Discovery Of The Centipede Scolopocryptops Gracilis Wood In Montana (Scolopendromorpha: Scolopocryptopidae), Rowland M. Shelley, Diana Six Jan 2004

Discovery Of The Centipede Scolopocryptops Gracilis Wood In Montana (Scolopendromorpha: Scolopocryptopidae), Rowland M. Shelley, Diana Six

Ecosystem and Conservation Sciences Faculty Publications

No abstract provided.


Splicing Affects Presentation Of Rna Dimerization Signals In Hiv-2 In Vitro, Jean-Marc Lanchy, Quenna N. Szafran, J. Stephen Lodmell Jan 2004

Splicing Affects Presentation Of Rna Dimerization Signals In Hiv-2 In Vitro, Jean-Marc Lanchy, Quenna N. Szafran, J. Stephen Lodmell

Biological Sciences Faculty Publications

During retroviral replication, full-length viral RNAs are encapsidated into new virus particles, while spliced RNAs are excluded. The Retroviridae are unique among viruses in that infectious viral particles contain a dimer of two identical genomic RNA strands. A variety of experimental data has suggested that dimerization and encapsidation of full-length viral RNAs are linked processes, although whether dimerization is a prerequisite for encapsidation, or conversely, dimerization follows encapsidation, has not been firmly established. If dimerization was the sole determinant for encapsidation, then spliced viral RNAs might be expected to display a reduced capacity for dimerization, resulting in their exclusion from …