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2005

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Articles 121 - 150 of 505

Full-Text Articles in Biology

A New Species Of Streptanthus (Brassicaceae) From Three Peaks In Lake County, California, Rebecca W. Dolan, Richard O'Donnell Jul 2005

A New Species Of Streptanthus (Brassicaceae) From Three Peaks In Lake County, California, Rebecca W. Dolan, Richard O'Donnell

Scholarship and Professional Work - LAS

Streptanlhus vernalis is a newly described species inhabiting serpentine rock outcrops in the Three Peaks area in Lake County, California. Morphological and allozyme data indicate that this taxon is related to the S. morrisonii complex.


Protection Against Experimental Autoimmune Myocarditis Is Mediated By Interleukin-10-Producing T Cells That Are Controlled By Dendritic Cells, Ya Li, Janet S. Heuser, Stanley D. Kosanke, Mark E. Hemric, Madeleine W. Cunningham Jul 2005

Protection Against Experimental Autoimmune Myocarditis Is Mediated By Interleukin-10-Producing T Cells That Are Controlled By Dendritic Cells, Ya Li, Janet S. Heuser, Stanley D. Kosanke, Mark E. Hemric, Madeleine W. Cunningham

Faculty Publications and Presentations

Experimental autoimmune myocarditis (EAM) can be induced in the Lewis rat by cardiac myosin or its cryptic S2-16 peptide epitope (amino acids1052 to 1076). To investigate cellular mechanisms and the role of antigen-presenting cells in regulation of myocarditis, we induced protection against EAM in Lewis rats by administration of S2-16 peptide in incomplete Freund’s adjuvant (IFA). Protection to EAM was associated with activation of S2-16-reactive splenocytes secreting high levels of interleukin (IL)-10 and reduced levels of interferon- and IL-2. Adoptive transfer of S2-16:IFA-induced splenocytes producing IL-10 suppressed myocarditis induction in syngeneic recipients, suggesting their regulatory cell nature. However, exposure of …


Unpalatable Plants Protect Neighbors From Grazing And Increase Plant Community Diversity, Ragan M. Callaway, David Kikodze, Marina Chiboshvili, Liana Khetsuriani Jul 2005

Unpalatable Plants Protect Neighbors From Grazing And Increase Plant Community Diversity, Ragan M. Callaway, David Kikodze, Marina Chiboshvili, Liana Khetsuriani

Biological Sciences Faculty Publications

Tasty plants can be protected from herbivores by unpalatable neighbors. We used experimental exclosures, removal of unpalatable species, and transplants of palatable and unpalatable species in subalpine meadows of the Caucasus Mountains of Georgia to study the effects of two unpalatable species on plant communities. We found that Cirsium obalatum and Veratrum lobelianum, two large native perennial herbs that invade after heavy grazing, had strong facilitative effects on communities through their indirect effects on livestock herbivores. These unpalatable invaders had different effects on community composition when livestock were present than when livestock were excluded. Furthermore, removing Cirsium and Veratrum …


Asymmetrical Competition And Patterns Of Abundance Of Aedes Albopictus And Culex Pipiens (Diptera : Culicidae), Katie S. Costanzo, Kimberly Mormann, Steven A. Juliano Jul 2005

Asymmetrical Competition And Patterns Of Abundance Of Aedes Albopictus And Culex Pipiens (Diptera : Culicidae), Katie S. Costanzo, Kimberly Mormann, Steven A. Juliano

Faculty Publications – Biological Sciences

We tested for competitive advantage among larvae of Aedes albopictus (Skuse) and Culex pipiens L. in a laboratory experiment and determined the frequency and spatial and temporal patterns of co-occurrence in the field in East St. Louis, IL. In a laboratory competition experiment at multiple combined densities of Ae. albopictus and Cx. pipiens larvae, Ae. albopictus survivorship, and developmental times were significantly affected by conspecific densities but not by Cx. pipiens densities. In contrast, Cx. pipiens survivorship, and developmental times were significantly affected by both conspecific and Ae. albopictus densities. Per capita rate of increase (r') for Ae. albopictus cohorts …


Review Of "The Microbial Models Of Molecular Biology: From Genes To Genomes" By R. H. Davis, Amy Cheng Vollmer, S. J. Vollmer Jul 2005

Review Of "The Microbial Models Of Molecular Biology: From Genes To Genomes" By R. H. Davis, Amy Cheng Vollmer, S. J. Vollmer

Biology Faculty Works

No abstract provided.


Evaluation Of Glycine Max Mrna Clusters, Ronald L. Frank, Fikret Erçal Jul 2005

Evaluation Of Glycine Max Mrna Clusters, Ronald L. Frank, Fikret Erçal

Biological Sciences Faculty Research & Creative Works

Background: Clustering the ESTs from a large dataset representing a single species is a convenient starting point for a number of investigations into gene discovery, genome evolution, expression patterns, and alternatively spliced transcripts. Several methods have been developed to accomplish this, the most widely available being UniGene, a public domain collection of gene-oriented clusters for over 45 different species created and maintained by NCBI. The goal is for each cluster to represent a unique gene, but currently it is not known how closely the overall results represent that reality. UniGene's build procedure begins with initial mRNA clusters before joining ESTs. …


Membrane Potential Oscillations In Reticulospinal And Spinobulbar Neurons During Locomotor Activity, James F. Einum, James T. Buchanan Jul 2005

Membrane Potential Oscillations In Reticulospinal And Spinobulbar Neurons During Locomotor Activity, James F. Einum, James T. Buchanan

Biological Sciences Faculty Research and Publications

Feedback from the spinal locomotor networks provides rhythmic modulation of the membrane potential of reticulospinal (RS) neurons during locomotor activity. To further understand the origins of this rhythmic activity, the timings of the oscillations in spinobulbar (SB) neurons of the spinal cord and in RS neurons of the posterior and middle rhombencephalic reticular nuclei were measured using intracellular microelectrode recordings in the isolated brain stem-spinal cord preparation of the lamprey. A diffusion barrier constructed just caudal to the obex allowed induction of locomotor activity in the spinal cord by bath application of an excitatory amino acid to the spinal bath. …


Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis Jun 2005

Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis

Theses and Dissertations

Ice crawlers (Insecta: Grylloblattodea) are rarely encountered insects that consist of five genera representing 26 species from North America and Asia. Asian grylloblattids are the most diverse, but North American ice crawlers (genus Grylloblatta) are known for their adaptation to cold conditions. Phylogenetic relationships among grylloblattid species and genera are not known. Late Pleistocene glaciations had a major effect on the current Grylloblatta distribution, because their specific habitat requirements restrict them to small geographical areas. Six genes were sampled in 37 individuals for 18S rRNA, 28S rRNA, histone 3, 12S rRNA, 16S rRNA, and cytochrome oxidase II (COII) from 27 …


Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir Jun 2005

Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir

Biology

ABSTRACT: Prochlorococcus and Synechococcus are major prokaryotic primary producers in the oligotrophic oceans that may be affected by the climate-related increases in nitrogen fixation and subsequent phosphorus (P) limitation in some parts of the oceans. Evidence that Prochlorococcus populations in the North Pacific subtropical gyre (NPSG) have increased over the past decades, possibly due to having a competitive advantage under conditions of P limitation, suggests aspects of their Pphysiology that are important for dictating their in situ success. Here, we compared the physiology of P acquisition and response to P stress (indicated by alkaline phosphatase activity, APA) among isolates of …


Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir Jun 2005

Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir

Faculty Publications

Prochlorococcus and Synechococcus are major prokaryotic primary producers in the oligotrophic oceans that may be affected by the climate-related increases in nitrogen fixation and subsequent phosphorus (P) limitation in some parts of the oceans. Evidence that Prochlorococcus populations in the North Pacific subtropical gyre (NPSG) have increased over the past decades, possibly due to having a competitive advantage under conditions of P limitation, suggests aspects of their Pphysiology that are important for dictating their in situ success. Here, we compared the physiology of P acquisition and response to P stress (indicated by alkaline phosphatase activity, APA) among isolates of Prochlorococcus …


Evaluating Forensic Dna Evidence, Dan E. Krane, William C. Thompson Jun 2005

Evaluating Forensic Dna Evidence, Dan E. Krane, William C. Thompson

Biological Sciences Faculty Publications

No abstract provided.


Carbon Cycling In Lake Superior, N. R. Urban, M. T. Auer, Sarah A. Green, X. Lu, D. S. Apul, K. D. Powell, L. Bub Jun 2005

Carbon Cycling In Lake Superior, N. R. Urban, M. T. Auer, Sarah A. Green, X. Lu, D. S. Apul, K. D. Powell, L. Bub

Department of Chemistry Publications

Carbon (C) cycling in Lake Superior was studied within the Keweenaw Interdisciplinary Transport Experiment in Superior (KITES) project to assess (1) whether the lake is net heterotrophic, (2) sources, sinks and residence time for dissolved organic carbon (DOC), (3) importance of terrigenous organic C subsidies, and (4) factors limiting C flow through bacteria. During 3 years of fieldwork, measurements were made of spatial and temporal distributions of C pools and rates of photosynthesis, community respiration, and bacterial production. Measurements were made of the composition of dissolved organic matter (DOM), rates of DOM photolysis, lability of DOM toward microbial consumption, and …


The Unionid Mussel Fauna Of Northeastern Ohio’S Grand River, Martin K. Huehner, Robert A. Krebs, Gregory Zimmerman, Melissa Mejia Jun 2005

The Unionid Mussel Fauna Of Northeastern Ohio’S Grand River, Martin K. Huehner, Robert A. Krebs, Gregory Zimmerman, Melissa Mejia

Biological, Geological, and Environmental Faculty Publications

Unionid mussel distribution, numbers, and species were examined in the Grand River to provide a recent and comprehensive study of mussels from northeast Ohio’s longest river. The entire length of the Grand was canoed and examined for unionid mussel beds, with the exception of upstream areas where the river was small; SCUBA was used to survey just upstream of Fairport Harbor. The lower river, designated Grand River’s Wild and Scenic section, was studied in 1995, the middle reaches, called the Scenic section, were surveyed in 1996, and completion of the headwater region followed in 1998. Finally, a survey near the …


Xiphiorhynchus Cf. X. Eocaenicus (Woodward, 1901), (Scombroidei: Xiphiidae: Xiphiorhynchinae) From The Middle Eocene Of Mississippi, The First Transatlantic Distribution Of A Species Of Xiphiorhynchus, Harry L. Fierstine, James E. Starnes Jun 2005

Xiphiorhynchus Cf. X. Eocaenicus (Woodward, 1901), (Scombroidei: Xiphiidae: Xiphiorhynchinae) From The Middle Eocene Of Mississippi, The First Transatlantic Distribution Of A Species Of Xiphiorhynchus, Harry L. Fierstine, James E. Starnes

Biological Sciences

An anterior (distal) rostrum (MMNS 2957) from the Moodys Branch Formation (late middle Eocene). Tesheva Creek, Yazoo County, Mississippi, U.S.A., is described and identified as Xiphiorhynchus cf. X. eocaenicus. The specimen is compared to various species of Xiphiorhynchus, especially the holotype of X. eocaenicl.ls (BMNH 25744), Braeklesham Group, early middle Eocene, England. This represents the first record of a species of Xiphiorhynchl.ls in deposits on both sides of the North Atlantic Ocean. Xiphiorhynchus eocaenicus is thought to have had similar environmental prtoferences and habits as the extant swordfish, Xiphias gladius. Since the swordfish prefers oceanic water and makes transatlantic movements, …


A New Aglyptorhynchus (Perciformes: Scombroidei) From The Lincoln Creek Formation (Late Oligocene, Washington, U.S.A.), Harry L. Fierstine Jun 2005

A New Aglyptorhynchus (Perciformes: Scombroidei) From The Lincoln Creek Formation (Late Oligocene, Washington, U.S.A.), Harry L. Fierstine

Biological Sciences

A partial rostrum with an attachcd lower jaw, a posterior neurocranium, and a proximal hyomandibular from the Lincoln Creek Formation (late Oligocene, Washington) arc described and identified as Aglyptorhynchlls coillmhianlls sp, nov. In addition. ten articulated anterior caudal vertebrae presumably from the Lincoln Creek Formation arc described and identified as Aglyptorhyllchlls sp. This is a second record of an Aglyptorhynchus from a deposit bordering the Pacific Ocean, The specimens are compared with other billfishes (Perciformes: Scombroidei), both extant and extinct. Unusual features include a tripartite celous occipital condyle composed equally of the basioccipital and cxoccipitals, a lower jaw that is …


Sexual Size Dimorphism And Growth Plasticity In Snakes: An Experiment On The Western Diamond‐Backed Rattlesnake (Crotalus Atrox), Emily N, Taylor, Dale F. Denardo Jun 2005

Sexual Size Dimorphism And Growth Plasticity In Snakes: An Experiment On The Western Diamond‐Backed Rattlesnake (Crotalus Atrox), Emily N, Taylor, Dale F. Denardo

Biological Sciences

We conducted an experiment to examine the effects of sex and food intake on growth, mass gain, and attainment of sexual maturity in Western Diamond‐backed Rattlesnakes (Crotalus atrox). We also measured testosterone levels to determine whether testosterone might be involved in the male‐biased sexual size dimorphism observed in this species. We collected neonate rattlesnakes and raised them in the laboratory for 2 years on either a high‐intake diet (fed one mouse per week) or a low‐intake diet (fed one mouse every 3 weeks). High‐intake snakes grew and gained mass more rapidly than low‐intake snakes, but males did not …


Effects Of Food Supplementation On The Physiological Ecology Of Female Western Diamond‐Backed Rattlesnakes (Crotalus Atrox), Emily N. Taylor, Michael A. Malawy, Dawn M. Browning, Shea V. Lemar, Dale F. Denardo Jun 2005

Effects Of Food Supplementation On The Physiological Ecology Of Female Western Diamond‐Backed Rattlesnakes (Crotalus Atrox), Emily N. Taylor, Michael A. Malawy, Dawn M. Browning, Shea V. Lemar, Dale F. Denardo

Biological Sciences

Food availability is an important factor in the life histories of organisms because it is often limiting and thus can affect growth, mass change, reproduction, and behaviors such as thermoregulation, locomotion, and mating. Experimental studies in natural settings allow researchers to examine the effects of food on these parameters while animals are free to behave naturally. The wide variation among organisms in energy demands and among environmental food resources suggest that responses to changes in food availability may vary among organisms. Since most supplemental feeding field experiments have been conducted on species with high energy demands, we conducted a supplemental …


Linking Patterns And Processes In Alpine Plant Communities: A Global Study, Zaal Kikvidze, Francisco I. Pugnaire, Robin W. Brooker, Philippe Choler, Christopher J. Lortie, Richard Michalet, Ragan M. Callaway Jun 2005

Linking Patterns And Processes In Alpine Plant Communities: A Global Study, Zaal Kikvidze, Francisco I. Pugnaire, Robin W. Brooker, Philippe Choler, Christopher J. Lortie, Richard Michalet, Ragan M. Callaway

Biological Sciences Faculty Publications

Predictable relationships among patterns, processes, and properties of plant communities are crucial for developing meaningful conceptual models in community ecology. We studied such relationships in 18 plant communities spread throughout nine Northern Hemisphere high-mountain subalpine and alpine meadow systems and found linear and curvilinear correlative links among temperature, precipitation, productivity, plant interactions, spatial pattern, and richness. We found that sites with comparatively mild climates have greater plant biomass, and at these sites strong competition corresponds with overdispersed distribution of plants, reducing intraspecific patchiness and in turn increasing local richness. Sites with cold climates have little biomass, and at these sites …


A Phylogenomic Study Of The Genus Alphavirus Employing Whole Genome Comparison, Aimée J. Luers, Sandra Adams, John V. Smalley, James Campanella Jun 2005

A Phylogenomic Study Of The Genus Alphavirus Employing Whole Genome Comparison, Aimée J. Luers, Sandra Adams, John V. Smalley, James Campanella

Department of Biology Faculty Scholarship and Creative Works

The phylogenetics of the genus Alphavirus have historically been characterized using partial gene, single gene or partial proteomic data. We have mined cDNA and amino acid sequences from GenBank for all fully sequenced and some partially sequenced alphaviruses and generated phylogenomic analyses of the genus Alphavirus genus, employing capsid encoding structural regions, non-structural coding regions and complete viral genomes. Our studies support the presence of the previously reported recombination event that produced the Western Equine Encephalitis clade, and confirm many of the patterns of geographic radiation and divergence of the multiple species. Our data suggest that the Salmon Pancreatic Disease …


Environmental, Genetic, And Maternal Effects On Life-History Traits Of The Striped Ground Cricket, Allonemobius Socius, Diana Lea Huestis Jun 2005

Environmental, Genetic, And Maternal Effects On Life-History Traits Of The Striped Ground Cricket, Allonemobius Socius, Diana Lea Huestis

Biology Theses - Archive

Organismal fitness is affected by environmental and genetic factors. More importantly, an interaction between an individual's genotype and current environmental conditions influences the success of that individual in its environment. Significant geographic and environmental correlates of allele frequencies at the Idh-1 locus, combined with a significant genotype-by-environment (GxE) interaction between Idh-1 genotype and temperature that affected fitness of Allonemobius socius, support the hypothesis that allele distributions in this species are the result of natural selection on performance of different genotypes at different temperatures. Additionally, I found that an interaction between parental diapause history and egg-incubation temperature affected the proportion of …


The Effects Of Socioeconomic Development On Worldwide Hepatitis A Virus Seroprevalence Patterns, Kathryn H. Jacobsen, James S. Koopman Jun 2005

The Effects Of Socioeconomic Development On Worldwide Hepatitis A Virus Seroprevalence Patterns, Kathryn H. Jacobsen, James S. Koopman

University Faculty Publications and Creative Works

Hepatitis A virus (HAV) infection confers long-term immunity, so mathematical analysis of age-specific seroprevalence in populations can reveal changes in the infection rate over time. HAV transmission is related to access to clean drinking water, personal hygiene and public sanitation. Methods: We used an SIR (susceptible-infectious-recovered) compartmental model with age structure to fit a time-dependent logistic function for HAV force of infection for 157 published age-seroprevalence data sets. We then fit linear regression models for socioeconomic variables and infection rate. Results: The proportion of the population with access to clean drinking water, the value of the human development index (HDI), …


Fisheries Occasional Publication No.21 - Allocation Of The Western Rock Lobster Resource Between User Groups, Department Of Fisheries Western Australia Jun 2005

Fisheries Occasional Publication No.21 - Allocation Of The Western Rock Lobster Resource Between User Groups, Department Of Fisheries Western Australia

Fisheries Occasional Publications

In this submission to IFAAC, the Department will outline what it believes are the most practical and cost effective ways of managing a system of allocation amongst the commercial, customary and recreational sectors. This recommendation recognises that cost efficiencies and outcomes will be greatly affected by the type of allocation model that is chosen. Consequently the Department recommends that the allocation system should be based on a single allocation to each sector that is available over the entire fishery.

The Department does not recommend having any finer scale zoning of the allocations, or the creation of exclusive recreational fishing areas. …


Stress Tolerance And Competitive-Response Ability Determine The Outcome Of Biotic Interactions, Pierre Liancourt, Ragan M. Callaway, Richard Michalet Jun 2005

Stress Tolerance And Competitive-Response Ability Determine The Outcome Of Biotic Interactions, Pierre Liancourt, Ragan M. Callaway, Richard Michalet

Biological Sciences Faculty Publications

Theoretical models predict that the net outcome of biotic interactions among plants is the sum of co-occurring negative and positive interactions, with facilitation generally increasing in importance with increasing abiotic stress. However, species differ in fundamental niche optima; thus the intensity of stress is relative among species and important only in the context of these relative differences. We tested the hypothesis that the facilitative response of a species is relative to how much abiotic conditions deviate from the optimum conditions for that particular species (stress), and the competitive “response” ability of the species (i.e., its ability to tolerate the inhibitory …


Plasticity In Selective Phonotaxis And Neuronal Responses Of Acheta Domesticus, Benjamin Alejandro Navia Jun 2005

Plasticity In Selective Phonotaxis And Neuronal Responses Of Acheta Domesticus, Benjamin Alejandro Navia

Loma Linda University Electronic Theses, Dissertations & Projects

Plasticity of phonotaxis in Acheta domesticus was evaluated in 207 young (5-7 days) and 328 old (28 days) female crickets. Of those that responded (508), their phonotaxis was grouped into selective (80% of young and 34% of old) and unselective (66% of old and 20% of young) on the basis of their responses to syllable period (SP). Two additional subcategories were also found. Some females were selective to the longer syllable periods (18% young, 20% old) while others were selective to the shorter syllable periods (7% young and 12% old). The L3 prothoracic auditory interneuron exhibits a decrementing response to …


Taxonomic Revision And Stratigraphic Provenance Of Histiophorus Rotundus Woodward 1901 (Teleostei, Perciformes), Kenneth A. Monsch, Harry L. Fierstine, Robert E. Weems Jun 2005

Taxonomic Revision And Stratigraphic Provenance Of Histiophorus Rotundus Woodward 1901 (Teleostei, Perciformes), Kenneth A. Monsch, Harry L. Fierstine, Robert E. Weems

Biological Sciences

Until recently, Histiophorus rotundus Woodward 1901, was known from a single, poorly preserved rostrum from the Tertiary phosphate beds near Charleston, South Carolina, an area from which many fossils have been described. The specimen is relatively featureless externally; its internal anatomy is unknown and the documentation of its geological provenance was poor. In an earlier revision the species was transferred to the fossil billfish genus Xiphiorhynchus Van Beneden, 1871. Here we confirm this designation, supported by new morphological studies of the holotype, recently found specimens of tXiphiorhynchus rotundus (Woodward, 1901), and the stratigraphic record of tXiphiorhynchus. The systematic paleontology we …


Reductionism And Holism, Chance And Selection, Mechanism And Mind, Ursula Goodenough Jun 2005

Reductionism And Holism, Chance And Selection, Mechanism And Mind, Ursula Goodenough

Biology Faculty Research

Despite its rich and deepening panoply of empirical support, evolutionary theory continues to generate widespread concern. Some of this concern can be attributed to misunderstandings of the original concept, some to unfamiliarity with its current trajectories, and some to strongly held fears that it strips the human of cherished attributes. In this essay I seek to deconstruct such misunderstandings, lift up current concepts of what evolution entails, and address some of the existential issues it generates.


Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang May 2005

Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang

Dissertations

Messenger RNA polyadenylation is one of the key post-transcriptional events in mammalian cells, which have influences on many aspects of mRNA metabolism. Several human diseases have been shown to associate with abnormal polyadenylation, highlighting the importance of this process. The availability of the complete sequence of human and mouse genomes, together with their gene expression data provides valuable resources to study mRNA polyadenylation on a system level. This dissertation addresses the following issues of mammalian mRNA polyadenylation through bioinformatics approaches: (1) the extensive documentation of several key aspects of polyadenylation sites in humans and mice on a genomic level; (2) …


Interspecific Divergence In Foliar Nutrient Dynamics And Stem Growth In A Temperate Forest In Response To Chronic Nitrogen Inputs, Jeffrey D. May, Sarah Beth Burdette, Frank S. Gilliam, Mary Beth Adams May 2005

Interspecific Divergence In Foliar Nutrient Dynamics And Stem Growth In A Temperate Forest In Response To Chronic Nitrogen Inputs, Jeffrey D. May, Sarah Beth Burdette, Frank S. Gilliam, Mary Beth Adams

Biological Sciences Faculty Research

We studied the effects of excessive nitrogen (N) fertilization on foliar nutrient dynamics and stem growth in three important tree species in a mixed-deciduous forest. Stem diameter growth, foliar N concentrations, nitrogen–phosphorus (N/P) ratios, and nutrient resorption were determined for Acer rubrum L. (ACRU), Liriodendron tulipifera L. (LITU), and Prunus serotina Ehrh. (PRSE) on two 30-year-old watersheds at the Fernow Experimental Forest, West Virginia, USA: WS3, fertilized annually with 35 kg ammonium sulfate·ha-1 since 1989, and WS7, an untreated control watershed. In an earlier (1992) study, foliar N concentrations of all three species averaged 11% higher in WS3 than …


Cellulose Utilization By Clostridium Thermocellum: Bioenergetics And Hydrolysis Product Assimilation, Yi-Heng P. Zhang, Lee R. Lynd May 2005

Cellulose Utilization By Clostridium Thermocellum: Bioenergetics And Hydrolysis Product Assimilation, Yi-Heng P. Zhang, Lee R. Lynd

Dartmouth Scholarship

The bioenergetics of cellulose utilization by Clostridium thermocellum was investigated. Cell yield and maintenance parameters, Y(X/ATP)True = 16.44 g cell/mol ATP and m = 3.27 mmol ATP/g cell per hour, were obtained from cellobiose-grown chemostats, and it was shown that one ATP is required per glucan transported. Experimentally determined values for G(ATP)P-T (ATP from phosphorolytic beta-glucan cleavage minus ATP for substrate transport, mol ATP/mol hexose) from chemostats fed beta-glucans with degree of polymerization (DP) 2-6 agreed well with the predicted value of (n-2)/n [corrected] (n = mean cellodextrin DP assimilated). A mean G(ATP)(P-T) value of 0.52 +/- 0.06 was calculated …


An Overview Of The 2nd National Invasive Rodent Summit, Gary Witmer, John D. Eisemann May 2005

An Overview Of The 2nd National Invasive Rodent Summit, Gary Witmer, John D. Eisemann

Wildlife Damage Management Conference

On October 19-21, 2004, the USDA, APHIS, Wildlife Services, National Wildlife Research Center (NWRC) in Fort Collins, CO, hosted the 2nd National Invasive Rodent Summit. The conference was jointly sponsored by the NWRC, the U.S. Fish and Wildlife Service (FWS) and The Wildlife Society's Wildlife Damage Management Working Group. The conference was a follow-up to the 2001 "Rat Summit" held in San Francisco, CA. Like the "Rat Summit," this conference emphasized the management of rodents to conserve plants, other wildlife and habitats. The scope of the problem, concerns, species involved, and lands affected were all considered. The conference began with …