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Articles 421 - 450 of 530

Full-Text Articles in Biology

Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee Jan 2005

Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee

Biological Sciences Faculty Publications

Toxicity and its detection in the dinoflagellate fish predators Pfiesteria piscicida and Pfiesteria shumwayae depend on the strain and the use of reliable assays. Two assays, standardized fish bioassays (SFBs) with juvenile fish and fish microassays (FMAs) with larval fish, were compared for their utility to detect toxic Pfiesteria. The comparison included strains with confirmed toxicity, negative controls (noninducible Pfiesteria strains and a related nontoxic cryptoperidiniopsoid dinoflagellate), and P. shumwayae strain CCMP2089, which previously had been reported as nontoxic. SFBs, standardized by using toxic Pfiesteria (coupled with tests confirming Pfiesteria toxin) and conditions conducive to toxicity expression, reliably detected …

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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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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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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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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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Correction [To Maurakis And Grimes Article, V. 54, #3&4] Oct 2004

Correction [To Maurakis And Grimes Article, V. 54, #3&4]

Virginia Journal of Science

This page is a correction to an article by Eugene G. Maurakis and David V. Grimes: Predicting Fish Species Diversity in Lotic Freshwaters of Greece, published in Virginia Journal of Science Volume 54, numbers 3 and 4. Amended table 2a owed to a printing corruption.

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Subterranean Loss And Gain Of Water In Mountain Lake, Virginia: A Hydrologic Model, Martin Jansons, Bruce C. Parker, Jacob E. Waller Oct 2004

Subterranean Loss And Gain Of Water In Mountain Lake, Virginia: A Hydrologic Model, Martin Jansons, Bruce C. Parker, Jacob E. Waller

Virginia Journal of Science

Mountain Lake, Virginia is a small, unique, oligotrophic, subalpine ecosystem in the southern Appalachians. Previous studies have disclosed that this lake has manifested periodic prolonged low water levels during the several thousand years of its existence. The most recent low water level occurred during the drought years of 1999-2002. Measurements of lake level, precipitation, and other meteorological data including calculated evapotranspiration in the lake basin from 2/19/02 to 8/31/03 have enabled estimation of net subterranean water losses presumably through cracks between Clinch sandstone boulders and/or the recently discovered deep hole at the northwest end of Mountain Lake. These net losses …

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Nest-Building And Spawning Behaviors In Nocomis Effusus (Actinopterygii: Cyprindae), Eugene G. Maurakis, George E. Maurakis Oct 2004

Nest-Building And Spawning Behaviors In Nocomis Effusus (Actinopterygii: Cyprindae), Eugene G. Maurakis, George E. Maurakis

Virginia Journal of Science

Spawning behavior in Nocomis effusus is described from direct observations and review of videotapes made in Yellow Creek (Cumberland River drainage), Tennessee in 2003. Nest construction (i.e., excavating a concavity, forming a platform, and building a mound), and spawning behavior in N. effusus where a single breeding male excavates a pit and spawns with females on the upstream slope of his nest is like that described for Nocomis asper and Nocomis biguttatus. In digging a spawning pit, a male N. effusus reshapes and reorganizes substrate materials that results in spawning areas on the upstream slope of the nest composed …

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Recently Elected Fellows Apr 2004

Recently Elected Fellows

Virginia Journal of Science

The Virginia Academy of Science elected three scientists at the 2004 Banquet: Harold G Marshall, Rosemary Barra, and Arthur F. Conway.

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Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose Jan 2004

Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose

Virginia Journal of Science

As part of a larger study examining the role of prescribed fire in regenerating upland oaks (Quercus spp.), seasonal prescribed burns (winter, spring, summer, and unburned control) were applied to first-stage shelterwood-harvested stands on Horsepen Wildlife Management Area in the Virginia Piedmont in 1995. Because fire impacts are poorly documented for herpetofaunal communities, we surveyed these stands in 1996 capturing 133 individuals of ten species during over 12,720 pitfall trapnights. We found no significant differences in relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus) (P = 0.26), American Toads (Bufo americanus) (P = 0.93), …

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On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall Jan 2004

On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall

Biological Sciences Faculty Publications

Plant and animal populations are frequently found in habitats where the environmental conditions are considered extreme or challenging for life form to exist. These conditions may be classified as either: (1) Supreme: a situation characteristic of degradation conditions where only a few species live under stress, and (2) Extra-ordinary: habitats that provide high biodiversity that are under stress conditions. Due to the differences in what we consider extreme conditions, it is necessary to distinguish between these two categories, because they are not comparable. Our presentation will include examples of these two extreme environmental categories.

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Creating A Geographical Information System For Freshwater Crabs And Fishes In Greece, Eugene G. Maurakis, Walter R.T. Witschey, Panos S. Economidis, Dimitra Bobori Oct 2003

Creating A Geographical Information System For Freshwater Crabs And Fishes In Greece, Eugene G. Maurakis, Walter R.T. Witschey, Panos S. Economidis, Dimitra Bobori

Virginia Journal of Science

A geographical information system (GIS) for freshwater crabs and fishes in Greece was created in response to the European Environmental Agency's (EEA) biodiversity initiative for European Union countries. A total of 1931 collections, made with seines, dipnets, and backpack electroshockers in 32 drainages of Greece, yielded 126 species of fishes and crabs in 2,359 data records including species, latitude, longitude, drainage, prefecture, and locality, 731 also include stream order, elevation, gradient, stream width and depth, pH, temperature, and distance to river mouth. Our GIS indicates current distributions of species, species rich and poor areas, anomalous species distributions, areas warranting further …

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An Unusually Colored Red-Backed Salamander (Plethodon Cinerus) From Northern Virginia, Joseph C. Mitchell, Thomas K. Pauley, C. Todd Georgel Apr 2003

An Unusually Colored Red-Backed Salamander (Plethodon Cinerus) From Northern Virginia, Joseph C. Mitchell, Thomas K. Pauley, C. Todd Georgel

Virginia Journal of Science

We describe an orange-pink, patternless, translucent morph of the Red-backed Salamander (Plethodon cinereus) found in northern Virginia on 27 September 2001. This is the first description of this unusual phenotype in this terrestrial salamander.

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Keys To The Mammals And Mammal Skulls Of The Northern Coastal Plain Of Virginia, John F. Pagels, A. Scott Bellows, Joseph C. Mitchell Apr 2003

Keys To The Mammals And Mammal Skulls Of The Northern Coastal Plain Of Virginia, John F. Pagels, A. Scott Bellows, Joseph C. Mitchell

Virginia Journal of Science

This publication is designed to function as a tool for the identification of mammal species that occur on the Coastal Plain of northern Virginia. We provide whole-body and skull keys to the 40 species that occur in this region. Baseline data for this work were collected during several studies conducted on Fort A.P. Hill, Caroline County. The intended audience includes interested naturalists, teachers, students, field biologists, and natural resource managers.

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Increase In Biomass And Soldier Production For Coptotermes Formosanus (Shiraki) Workers Maintained In The Laboratory For Up To Nine Months, Deborah Waller Jan 2003

Increase In Biomass And Soldier Production For Coptotermes Formosanus (Shiraki) Workers Maintained In The Laboratory For Up To Nine Months, Deborah Waller

Biological Sciences Faculty Publications

The factors that influence rates of soldier production in subterranean termites are poorly understood. In the present study, foraging groups of Coptotermes formosanus Shiraki were collected from baldcypress trees in Lake Charles, Lousiana, in November 1985, and February, April/May and August 1986. Termites were maintained in the laboratory for nine months, seven months, four/five months and zero months, respectively, and then examined for survivorship, termite biomass and soldier production after incubation for an additional five weeks at 30° C. Within collection periods, there was no association between survivorship and soldier production or between mean dry biomass and soldier production. However, …

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Algal Composition And Abundance In The Neuston Surface Micro Layer From A Lake And Pond In Virginia (U.S.A.), Lubomira Burchardt, Harold G. Marshall Jan 2003

Algal Composition And Abundance In The Neuston Surface Micro Layer From A Lake And Pond In Virginia (U.S.A.), Lubomira Burchardt, Harold G. Marshall

Biological Sciences Faculty Publications

A comparative study was conducted that characterized the algae within the neuston, ca 2 mm below the surface, and the algae in the water column from two freshwater habitats. There were significant differences in total algal abundance and the abundance of diatoms, cyanoprokaryotes, and chlorophytes between the neuston and water column algae of these two regions during each season and at both sites. The pond neuston was dominated by chlorophytes, with total algal abundance ranging seasonally from 0.6 to 59.6 x 10-3 cells ml-1 compared to water column algal concentrations of 4.1 to 40.4 x 10-3 cells ml-1. …

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Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber Oct 2002

Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber

Virginia Journal of Science

Antibiotic Resistance Patterns (ARPs) of Enterococcus spp. were used as a phenotypic fingerprint to compare and categorize unknown-source isolates in an impaired segment of the Roanoke River, Roanoke County, Virginia. Antibiotic resistance analysis (ARA) of enterococci has been effectively used to differentiate among sources of fecal contamination in many geographic regions in the United States. Enterococcus spp. were used as a fecal indicator in a library consisting of 1,562 known-source isolates. Two-way analysis indicated that approximately 95% of the unknown-source isolates collected were of animal origin. A 3-way analysis indicated that 61% of the unknowns were of livestock origin while …

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Histological Evaluation Of Cryopreserved Ovaries In Autologous Abdominal Transplant To NaïVe, Outbred, Cd1, Mice, Wentia Elissa Ford Oct 2002

Histological Evaluation Of Cryopreserved Ovaries In Autologous Abdominal Transplant To NaïVe, Outbred, Cd1, Mice, Wentia Elissa Ford

Biological Sciences Theses & Dissertations

This study showed that fresh and frozen-thawed mouse ovaries would maintain viable primordial or primary follicles post-autologous transplantation. Furthermore, with appropriate hormonal stimulation, these early-stage follicles were shown to develop into Graafian follicles containing a metaphase II antral ovum. Partially sliced ovaries were transplanted into the abdominal cavity of naive, outbred, CD1, white mice. Hormonal stimulation with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) one week after the autologous transplantation stimulated variable degrees of follicle and ovum maturation within the ovarian tissue. There were no major morphological differences observed between the four groups, three treatment and one …

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Determination Of Nuclear Factor-Kappa B Activation In Cultured Renal Epithelial Cells And Cardiac Myocytes Exposed To Cocaine And Morphine, David Angeles Tiangco Apr 2002

Determination Of Nuclear Factor-Kappa B Activation In Cultured Renal Epithelial Cells And Cardiac Myocytes Exposed To Cocaine And Morphine, David Angeles Tiangco

Biological Sciences Theses & Dissertations

Nuclear factor-kappa B (NF-kB) is an important transcription factor that participates in the genetic regulation of inflammation in many tissues. Cocaine and heroin are drugs of abuse associated with renal and cardiac pathology. The purpose of this study was to test the hypothesis that exposure to cocaine or morphine (a metabolite of heroin) would activate NF-kB in renal epithelial cells (COS-7) and cardiac myocytes (H9c2) grown in culture. COS-7 and H9c2 cells were co-transfected with an experimental reporter specific for NF-kB activation and a control reporter with constitutive activity. A dual-luciferase assay was used to determine levels of NF-kB activation …

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A Baseline Assessment Of Furbearers On The Upper Coastal Plain Of Virginia, A. Scott Bellows, Joseph C. Mitchell Jan 2002

A Baseline Assessment Of Furbearers On The Upper Coastal Plain Of Virginia, A. Scott Bellows, Joseph C. Mitchell

Virginia Journal of Science

We assessed the status of furbearing mammals on Fort A.P. Hill, Caroline County, Virginia during the 1998-1999 trapping season with the cooperation of local licensed trappers. Our analyses were based on 345 captures representing of 10 mammal species, ranging from one bobcat (Lynx rufus) to 157 beavers (Castor canadensis). Mean number of captures per 100 trap nights was 17.0. Captures varied from 11.9 to 17.9 per 100 trap nights for conibear traps and 9.7 to 18.3 per 100 trap nights for leg-hold traps. External measurements of six species were similar to those reported for other populations …

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Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva Jan 2002

Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva

Biological Sciences Faculty Publications

We evaluated an artificial capillary feeding method to infect nymphal Ixodes scapularis (Say) ticks with Borrelia burgdorferi, the causative agent of Lyme disease. Thirty to 70% of the nymphs were infected after feeding for 2.5 h from glass capillary tubes filled with a solution of spirochetes. Capillary infection was stable and persisted in the nymphs for at least 10 d after feeding. Capillary feeding also maintained natural vector competence patterns because I. scapularis ticks acquired infection unlike Dermacentor variablis (Say), which did not become infected. Capillary infected I. scapularis nymphs were capable of transmitting the infection to naive mice …

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In Vivo Effect Of Leukemia Inhibitory Factor (Lif) And An Anti-Lif Polyclonal Antibody On Murine Embryo And Fetal Development Following Exposure At The Time Of Transcervical Blastocyst Transfer, Michael H. Mitchell, R. James Swanson, Sergio Oehninger Jan 2002

In Vivo Effect Of Leukemia Inhibitory Factor (Lif) And An Anti-Lif Polyclonal Antibody On Murine Embryo And Fetal Development Following Exposure At The Time Of Transcervical Blastocyst Transfer, Michael H. Mitchell, R. James Swanson, Sergio Oehninger

Biological Sciences Faculty Publications

Leukemia inhibitory factor (LIF) enhances in vitro murine preimplantation development in a time- and dose-dependent fashion. Knockout experiments have demonstrated that endometrial LIF is essential for in vivo murine implantation. We assessed the impact of LIF and an anti-LIF polyclonal antibody (pab) on in vivo development and developed a novel and successful nonsurgical method of embryo transfer for this species, a transcervical blastocyst transfer technique. The objectives of this study were to evaluate the effects of LIF and the anti-LIF pab on 1) implantation, resorption, pregnancy, and viability rates and 2) the overall structural and skeletal development. Two-cell embryos were …

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Length-At-Age In Juvenile Patagonian Toothfish (Dissostichus Eleginoides), J. Ashford, C. Jones, S. Bobko, I. Everson Jan 2002

Length-At-Age In Juvenile Patagonian Toothfish (Dissostichus Eleginoides), J. Ashford, C. Jones, S. Bobko, I. Everson

OES Faculty Publications

We used the otoliths from a sample of Dissostichus eleginoides pre-recruits, whose length density was distinctly polymodal, to see whether ages estimated by reading otoliths were congruent with the length modes observed. Length densities by age were compared graphically with the overall length density observed. Additionally, ages were predicted for each fish based on length, and compared with ages estimated from reading otoliths in a goodness-of-fit test. The majority of the otoliths (83.6%) were estimated to be from fish 1+ or 2+ years old, with mean total lengths of 32.5 cm and 41.3 cm respectively. No difference was found between …

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Mammals Of Fort A. P. Hill, Caroline County, Virginia And Vicinity, A. Scott Bellows, Joseph C. Mitchell, John F. Pagels, Heather N. Mansfield Oct 2001

Mammals Of Fort A. P. Hill, Caroline County, Virginia And Vicinity, A. Scott Bellows, Joseph C. Mitchell, John F. Pagels, Heather N. Mansfield

Virginia Journal of Science

Fort A.P. Hill (APH) is a 30,329 ha military training installation (U.S. Army) located in the upper Coastal Plain of Caroline County, Virginia. It was formed in 1941 and named in honor of Civil War Confederate Lt. General Ambrose Powell Hill. The current landscape includes a mosaic of habitats that range from old fields to hardwood forests. Forty species of mammals are known to exist on or near the installation. These include one marsupial, five insectivores, 9 chiropterans, one lagomorph, 12 rodents, 10 carnivores, and one cervid. We have studied many of the species on APH since 1997. In this …

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Environmental Effects On Yield And Agronomic Traits Of Common Bean (Phaseolus Vulgaris L.), Tadesse Mebrahtu, Teklu Andebrhan, Ali Mohamed Apr 2001

Environmental Effects On Yield And Agronomic Traits Of Common Bean (Phaseolus Vulgaris L.), Tadesse Mebrahtu, Teklu Andebrhan, Ali Mohamed

Virginia Journal of Science

Common bean (Phaseolus vulgaris L.) demand is increasing with an alarming rate around the world, especially in Latin America, Africa, and Asia. Therefore, increase bean yield per hectare is the best way to meet the world demand rather than expansion of area under cultivation. The objectives of this experiment were to determine the genotypic variations for green bean and dry seed yield and magnitude of genotype x environment interaction effects on yield and yield components of common bean. Thirteen genotypes were planted during the 1992, 1994, and 1995 growing seasons. Genotypes were evaluated for green pod and seed …

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Isolation And Fusion Of Cotton Protoplasts, Michael H. Renfroe, Ronald C. Hartwig, Roberta H. Smith Apr 2001

Isolation And Fusion Of Cotton Protoplasts, Michael H. Renfroe, Ronald C. Hartwig, Roberta H. Smith

Virginia Journal of Science

Protoplasts were isolated from five species of Gossypium. Protoplast yield and viability were affected by incubation conditions, osmolarity, purification procedures, and cell source. Using an optimized procedure, highly viable protoplasts were isolated from cell suspensions, callus cultures, and leaf tissue of G. hirsutum, G. arboreum, G. klotzschianum, G. harknessii, and G. herbaceum. Protoplasts of G. harknessii were enucleated and successfully fused with protoplasts of G. hirsutum.

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Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware Apr 2001

Ice Storm Damage To Virginia Coastal Plain Forests During The Christmas 1998 Ice Storm, Peter Elstner, Stewart Ware

Virginia Journal of Science

On December 23-25, 1998, a major ice storm struck southeastern Virginia. The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between February and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Mary. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras albidum stems. As a group, small (2.5 to 15 …

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Comparison Of Spawning And Non-Spawning Substrates In Nests Of Species Of Exoglossum And Nocomis (Actinopterygii: Cyprinidae), Eugene G. Maurakis, Terre D. Green Apr 2001

Comparison Of Spawning And Non-Spawning Substrates In Nests Of Species Of Exoglossum And Nocomis (Actinopterygii: Cyprinidae), Eugene G. Maurakis, Terre D. Green

Virginia Journal of Science

Percent composition of pebble size classes from spawning and non-spawning substrates of nests were used to test the hypothesis that distribution of pebble sizes is random in nests of Exoglossum laurae, Exoglossum maxillingua, Nocomis leptocephalus, Nocomis micropogon, Nocomis platyrhynchus, and Nocomis raneyi in Virginia. In nests of the two species of Exoglossum, spawning areas (i.e., upstream bases of nests) contain significantly greater amounts of the 6.0 mm size class, and significantly smaller amounts of the 2.5 mm size class of stones than do non-spawning areas. Spawning areas (i.e., pits) in nests of N. leptocephalus contain …

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An Examination Of The First Sediment Cores From Mountain Lake, Giles County, Virginia, For Diatoms And Pollen, Jon C. Cawley, Bruce C. Parker, Terry L. Hufford Jan 2001

An Examination Of The First Sediment Cores From Mountain Lake, Giles County, Virginia, For Diatoms And Pollen, Jon C. Cawley, Bruce C. Parker, Terry L. Hufford

Virginia Journal of Science

Mountain Lake, Virginia is a small, unique, oligotrophic, subalpine ecosystem in the southern Appalachians. Its geology, origin, climate, and history have influenced its morphometry, and therefore its sedimentology and algal flora. Radiocarbon dates establish specific Mountain Lake sediment ages at 1800, 4100, and 6100 years BP. Sediment core analysis suggests at least 6 prolonged periods when Mountain Lake probably was nearly dry or very small in size. These individual low-water periods (at approximately 100, 400, 900, 1200, 1800 and 4100 years BP) are evidenced by changes in diatom and pollen content, sedimentary erosion features, and the presence of wood fragments, …

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