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The Strength Of B Cell Interaction With Antigen Determines The Degree Of Igm Polymerization, JM Ye, ES Bromage, SL Kaattari 2010 Virginia Institute of Marine Science

The Strength Of B Cell Interaction With Antigen Determines The Degree Of Igm Polymerization, Jm Ye, Es Bromage, Sl Kaattari

VIMS Articles

The induction of variable disulfide polymerization of IgM in the trout (Oncorhynchus mykiss) and its effect on its half-life were examined. An association between greater Ab affinity and increased disulfide polymerization was first indicated by the observation of this increased IgM disulfide polymerization during the process of affinity maturation. A direct association between Ab affinity and disulfide polymerization was then established by the fractionation of individual sera into high- and low-affinity subpopulations, which also resulted in the partitioning of high and low degrees of disulfide polymerization. The ability of high-affinity B cells to produce more highly polymerized Abs upon Ag ...


Temperature Effects On Growth, Colony Development And Carbon Partitioning In Three Phaeocystis Species, XD Wang, KW Tang, Y Wang, WO Smith 2010 Virginia Institute of Marine Science

Temperature Effects On Growth, Colony Development And Carbon Partitioning In Three Phaeocystis Species, Xd Wang, Kw Tang, Y Wang, Wo Smith

VIMS Articles

Phaeocystis is an ecologically important marine phytoplankton genus that is globally distributed. We examined the effects of temperature on the 3 most common species: P. globosa, P. antarctica, and P. pouchetii, which grew at 16-32, 0-6, and 4-8 degrees C, respectively. P. pouchetii did not form colonies; P. globosa formed colonies at 16, 20, and 24 degrees C, and P. antarctica colonies were observed at all temperatures. More cells were partitioned into the colonial form at lower temperatures than at higher temperatures for P. globosa and P. antarctica. P. globosa colony size decreased with temperature, whereas P. antarctica colony size ...


Nitrogen Uptake By Phytoplankton And Bacteria During An Induced Phaeocystis Pouchetii Bloom, Measured Using Size Fractionation And Flow Cytometric Sorting, PB Bradley, MP Sanderson, JC Nejstgaard, AF Sazhin, ME Frischer, LM Killberg-Thoreson, PG Verity, L Campbell, DA Bronk 2010 Virginia Institute of Marine Science

Nitrogen Uptake By Phytoplankton And Bacteria During An Induced Phaeocystis Pouchetii Bloom, Measured Using Size Fractionation And Flow Cytometric Sorting, Pb Bradley, Mp Sanderson, Jc Nejstgaard, Af Sazhin, Me Frischer, Lm Killberg-Thoreson, Pg Verity, L Campbell, Da Bronk

VIMS Articles

Uptake of inorganic and organic nitrogen (N) by phytoplankton and bacteria was investigated during a mesocosm study conducted in Raunefjord, Norway in April 2005. One mesocosm was fertilized with nitrate and phosphate at a ratio of 16:1 and maintained in the light, while one unamended light mesocosm served as a control. Dissolved nutrients, phytoplankton and bacterial biomass, and phytoplankton community composition were monitored throughout the 26 d experiment. Uptake of (15)N-labeled ammonium and nitrate, and dual-labeled ((15)N and (13)C) urea and dissolved free amino acids (DFAA) was measured for phytoplankton and bacteria using 2 methods: size ...


Linkage Between Crustacean Zooplankton And Aquatic Bacteria, KW Tang, V Turk, HP Grossart 2010 Virginia Institute of Marine Science

Linkage Between Crustacean Zooplankton And Aquatic Bacteria, Kw Tang, V Turk, Hp Grossart

VIMS Articles

Bacteria and metazoan zooplankton (mainly crustaceans) are often viewed as 2 separate functional groups in the pelagic food webs indirectly linked via nutrient cycling and trophic cascades. Yet a zooplankter's body carries a high abundance of diverse bacteria, often at an equivalent concentration orders of magnitude higher than the ambient bacterial concentration. Zooplankton bodies are organic-rich micro-environments that support fast bacterial growth. Their physical-chemical conditions differ from those in the surrounding water and therefore select for different bacterial communities, including anaerobic bacteria that otherwise may not thrive in a well-oxygenated water column. The zooplankton body provides protection to the ...


Oceanic Heterotrophic Bacterial Nutrition By Semilabile Dom As Revealed By Data Assimilative Modeling, YW Luo, MAM Friedrichs, SC Doney, MJ Church, HW Ducklow 2010 Virginia Institute of Marine Science

Oceanic Heterotrophic Bacterial Nutrition By Semilabile Dom As Revealed By Data Assimilative Modeling, Yw Luo, Mam Friedrichs, Sc Doney, Mj Church, Hw Ducklow

VIMS Articles

Previous studies have focused on the role of labile dissolved organic matter (DOM) (defined as turnover time of similar to 1 d) in supporting heterotrophic bacterial production, but have mostly neglected semilabile DOM (defined as turnover time of similar to 100 to 1000 d) as a potential substrate for heterotrophic bacterial growth. To test the hypothesis that semilabile DOM supports substantial amounts of heterotrophic bacterial production in the open ocean, we constructed a 1-dimensional epipelagic ecosystem model and applied it to 3 open ocean sites: the Arabian Sea, Equatorial Pacific and Station ALOHA in the North Pacific Subtropical Gyre. The ...


Asymmetric Conservation Benefits Of Circle Hooks In Multispecies Billfish Recreational Fisheries: A Synthesis Of Hook Performance And Analysis Of Blue Marlin (Makaira Nigricans) Postrelease Survival, John E. Graves, Andrij Z. Horodysky 2010 Virginia Institute of Marine Science

Asymmetric Conservation Benefits Of Circle Hooks In Multispecies Billfish Recreational Fisheries: A Synthesis Of Hook Performance And Analysis Of Blue Marlin (Makaira Nigricans) Postrelease Survival, John E. Graves, Andrij Z. Horodysky

VIMS Articles

We evaluated the conservation benefits of the use of circle hooks compared with standard J hooks in the recreational fishery for Atlantic istiophorid billfishes, noting hooking location and the presence of trauma (bleeding) for 123 blue marlin (Makaira nigricans), 272 white marlin (Kajikia albida), and 132 sailfish (Istiophorus platypterus) caught on natural baits rigged with one of the two hook types. In addition, we used pop-up satellite archival tags (PSATs) to follow the fate of 61 blue marlin caught on natural baits rigged with circle hooks or on a combination of artificial lure and natural bait rigged with J hooks ...


Regional Management Units For Marine Turtles: A Novel Framework For Prioritizing Conservation And Research Across Multiple Scales, Bryan P. Wallace, John A. Musick 2010 et al

Regional Management Units For Marine Turtles: A Novel Framework For Prioritizing Conservation And Research Across Multiple Scales, Bryan P. Wallace, John A. Musick

VIMS Articles

Background: Resolving threats to widely distributed marine megafauna requires definition of the geographic distributions of both the threats as well as the population unit(s) of interest. In turn, because individual threats can operate on varying spatial scales, their impacts can affect different segments of a population of the same species. Therefore, integration of multiple tools and techniques - including site-based monitoring, genetic analyses, mark-recapture studies and telemetry - can facilitate robust definitions of population segments at multiple biological and spatial scales to address different management and research challenges. Methodology/Principal Findings: To address these issues for marine turtles, we collated all ...


Evolutionary Characters, Phenotypes And Ontologies: Curating Data From The Systematic Biology Literature, Wasila M. Dahdul, Eric J. Hilton 2010 et al

Evolutionary Characters, Phenotypes And Ontologies: Curating Data From The Systematic Biology Literature, Wasila M. Dahdul, Eric J. Hilton

VIMS Articles

Background: The wealth of phenotypic descriptions documented in the published articles, monographs, and dissertations of phylogenetic systematics is traditionally reported in a free-text format, and it is therefore largely inaccessible for linkage to biological databases for genetics, development, and phenotypes, and difficult to manage for large-scale integrative work. The Phenoscape project aims to represent these complex and detailed descriptions with rich and formal semantics that are amenable to computation and integration with phenotype data from other fields of biology. This entails reconceptualizing the traditional free-text characters into the computable Entity-Quality (EQ) formalism using ontologies. Methodology/Principal Findings: We used ontologies ...


Dynamics And Distribution Of Natural And Human-Caused Hypoxia, N. N. Rabalais, Robert J. Diaz, L.A. Levin, R.E. Turner, D. Gilbert, J. Zhang 2010 Virginia Institute of Marine Science

Dynamics And Distribution Of Natural And Human-Caused Hypoxia, N. N. Rabalais, Robert J. Diaz, L.A. Levin, R.E. Turner, D. Gilbert, J. Zhang

VIMS Articles

Water masses can become undersaturated with oxygen when natural processes alone or in combination with anthropogenic processes produce enough organic carbon that is aerobically decomposed faster than the rate of oxygen re-aeration. The dominant natural processes usually involved are photosynthetic carbon production and microbial respiration. The re-supply rate is indirectly related to its isolation from the surface layer. Hypoxic water masses (< 2 mg L-1, or approximately 30% saturation) can form, therefore, under 'natural' conditions, and are more likely to occur in marine systems when the water residence time is extended, water exchange and ventilation are minimal, stratification occurs, and where carbon production and export to the bottom layer are relatively high. Hypoxia has occurred through geological time and naturally occurs in oxygen minimum zones, deep basins, eastern boundary upwelling systems, and fjords. Hypoxia development and continuation in many areas of the world's coastal ocean is accelerated by human activities, especially where nutrient loading increased in the Anthropocene. This higher loading set in motion a cascading set of events related to eutrophication. The formation of hypoxic areas has been exacerbated by any combination of interactions that increase primary production and accumulation of organic carbon leading to increased respiratory demand for oxygen below a seasonal or permanent pycnocline. Nutrient loading is likely to increase further as population growth and resource intensification rises, especially with increased dependency on crops using fertilizers, burning of fossil fuels, urbanization, and waste water generation. It is likely that the occurrence and persistence of hypoxia will be even more widespread and have more impacts than presently observed. Global climate change will further complicate the causative factors in both natural and human-caused hypoxia. The likelihood of strengthened stratification alone, from increased surface water temperature as the global climate warms, is sufficient to worsen hypoxia where it currently exists and facilitate its formation in additional waters. Increased precipitation that increases freshwater discharge and flux of nutrients will result in increased primary production in the receiving waters up to a point. The interplay of increased nutrients and stratification where they occur will aggravate and accelerate hypoxia. Changes in wind fields may expand oxygen minimum zones onto more continental shelf areas. On the other hand, not all regions will experience increased precipitation, some oceanic water temperatures may decrease as currents shift, and frequency and severity of tropical storms may increase and temporarily disrupt hypoxia more often. The consequences of global warming and climate change are effectively uncontrollable at least in the near term. On the other hand, the consequences of eutrophication-induced hypoxia can be reversed if long-term, broad-scale, and persistent efforts to reduce substantial nutrient loads are developed and implemented. In the face of globally expanding hypoxia, there is a need for water and resource managers to act now to reduce nutrient loads to maintain, at least, the current status.


Molecular Identification, Phylogeny And Geographic Distribution Of Brazilian Mangrove Oysters (Crassostrea), Aline Grasielle Costa de Melo, Kimberly S. Reece 2010 et al

Molecular Identification, Phylogeny And Geographic Distribution Of Brazilian Mangrove Oysters (Crassostrea), Aline Grasielle Costa De Melo, Kimberly S. Reece

VIMS Articles

Oysters (Ostreidae) manifest a high degree of phenotypic plasticity, whereby morphology is of limited value for species identification and taxonomy. By using molecular data, the aim was to genetically characterize the species of Crassostrea occurring along the Brazilian coast, and phylogenetically relate these to other Crassostrea from different parts of the world. Sequencing of the partial cytochrome oxidase c subunit I gene (COI), revealed a total of three species of Crassostrea at 16 locations along the Brazilian coast. C. gasar was found from Curuca (Para state) to Santos (Sao Paulo state), and C. rhizophorae from Fortim (Ceara state) to Florianopolis ...


Fate Of Macroalgae In Benthic Systems: Carbon And Nitrogen Cycling Within The Microbial Community, Amber K. Hardison, Elizabeth A. Canuel, Iris C. Anderson, Bart Veuger 2010 Virginia Institute of Marine Science

Fate Of Macroalgae In Benthic Systems: Carbon And Nitrogen Cycling Within The Microbial Community, Amber K. Hardison, Elizabeth A. Canuel, Iris C. Anderson, Bart Veuger

VIMS Articles

High nutrient loading to coastal bays is often accompanied by the presence of bloom-forming macroalgae, which take up and sequester large amounts of C and N while growing. This pool is temporary, however, as nuisance macroalgae exhibit a bloom and die-off cycle, influencing the biogeochemical functioning of these systems in unknown ways. The objective of this study was to trace the C and N from senescing macroalgae into relevant sediment pools. A macroalgal die-off event was simulated by the addition of freeze-dried macroalgae (Gracilaria spp.), pre-labeled with stable isotopes (C-13 and N-15), to sediment mesocosms. The isotopes were traced into ...


Net Removal Of Nitrogen Through Ingestion Of Phytoplankton By Atlantic Menhaden Brevoortia Tyrannus In Chesapeake Bay, Patrick D. Lynch, Mark J. Brush, Elizabeth D. Condon, Robert J. Latour 2010 Virginia Institute of Marine Science

Net Removal Of Nitrogen Through Ingestion Of Phytoplankton By Atlantic Menhaden Brevoortia Tyrannus In Chesapeake Bay, Patrick D. Lynch, Mark J. Brush, Elizabeth D. Condon, Robert J. Latour

VIMS Articles

As filter-feeding planktivores, Atlantic menhaden Brevoortia tyrannus have the potential to influence water quality through ingestion of phytoplankton and assimilation of resultant nutrients. To evaluate the influence of young-of-the-year (YOY) and age-1+ menhaden in Chesapeake Bay, rates of phytoplankton (chl a) ingestion and total dissolved nitrogen (TDN) excretion were measured experimentally across varying phytoplankton concentrations. Ingestion rates of YOY menhaden increased (0.03 to 185 mu g chl a fish(-1) min(-1)) in response to increasing phytoplankton concentration (4.98 to 198.22 mu g chl a l(-1)), while age-1+ menhaden exhibited virtually no ingestion of the phytoplankton ...


Growth, Reproductive Condition, And Digestive Tubule Atrophy Of Pacific Oyster Crassostrea Gigas In Gamakman Bay Off The Southern Coast Of Korea, DH Kang, Fu-Lin E. Chu, HS Yang, CH Lee, CH Lee, HB Koh, KS Choi 2010 Virginia Institute of Marine Science

Growth, Reproductive Condition, And Digestive Tubule Atrophy Of Pacific Oyster Crassostrea Gigas In Gamakman Bay Off The Southern Coast Of Korea, Dh Kang, Fu-Lin E. Chu, Hs Yang, Ch Lee, Ch Lee, Hb Koh, Ks Choi

VIMS Articles

Spat of Pacific oysters (Crassostrea gigas) were collected from Gamakman Bay, Korea, and raised in a spat hardening facility located in the low intertidal zone of the bay for a "hardening/stunting" period of 10 mo. Seasonal changes in growth, reproductive condition, and digestive tubule atrophy (DTA) of these "hardened/stunted" oysters were monitored for more than a year after transplanting to a suspended longline system in a grow-out area in the bay. After transplantation, the hardened/stunted oysters showed a logarithmic increase in shell size for the first 4 mo, from June to October, and growth remained stable from ...


Observations Of Blue Crabs (Callinectes Sapidus, Rathbun 1896) On Shell Bar Oyster Reef, Great Wicomico River, Virginia, Juliana Harding, Melissa Southworth, Roger L. Mann 2010 Virginia Institute of Marine Science

Observations Of Blue Crabs (Callinectes Sapidus, Rathbun 1896) On Shell Bar Oyster Reef, Great Wicomico River, Virginia, Juliana Harding, Melissa Southworth, Roger L. Mann

VIMS Articles

Blue crabs (Callinectes sapidus, Rathbun 1896) were sampled with commercial crab pots on Shell Bar oyster reef in the Great Wicomico River, VA, from May through October during 2006 and 2007. Weekly catch per unit effort (CPUE), sex ratio, and size (carapace width, measured in millimeters) were evaluated in the context of water temperature (measured in degrees Celsius), salinity, and daylength (measured in hours) conditions on the reef. The total number of crabs collected in 2006 and 2007 was 5,221 and 3,303, respectively. Blue crab CPU E was highest from mid-June through mid-September at water temperatures at or ...


Management Of The Piankatank River, Virginia, In Support Of Oyster (Crassostrea Virginica, Gmelin 1791) Fishery Repletion, Juliana M. Harding, Roger L. Mann, Melissa Southworth, James A. Wesson 2010 Virginia Institute of Marine Science

Management Of The Piankatank River, Virginia, In Support Of Oyster (Crassostrea Virginica, Gmelin 1791) Fishery Repletion, Juliana M. Harding, Roger L. Mann, Melissa Southworth, James A. Wesson

VIMS Articles

The Piankatank River is a trap-type estuary on the western shore of Chesapeake Bay that has been managed for seed oyster production since 1963. Market oyster production in the river is minimal. Repletion efforts include shell planting and seed removal. We describe sequential changes in population demographics and habitat in relation to repletion activities on eight Piankatank River public oyster reefs from 1998 through 2009. Two reef groups (northern and southern) may be distinguished by density (oysters/m(2)), biomass (e dry tissue weight), and shell volume (L/m(2)) data. Age-at-length relationships were estimated from demographic data using a ...


A Comparison Of Crassostrea Virginica And C. Ariakensis In Chesapeake Bay: Does Oyster Species Affect Habitat Function?, HD Harwell, PR Kingsley-Smith, M. Lisa Kellogg, Standish K. Allen Jr., DW Meritt, Kennedy Paynter, Mark Luckenbach 2010 Virginia Institute of Marine Science

A Comparison Of Crassostrea Virginica And C. Ariakensis In Chesapeake Bay: Does Oyster Species Affect Habitat Function?, Hd Harwell, Pr Kingsley-Smith, M. Lisa Kellogg, Standish K. Allen Jr., Dw Meritt, Kennedy Paynter, Mark Luckenbach

VIMS Articles

We examined the possibility that a nonnative oyster species would provide an ecologically functional equivalent of the native oyster species if introduced into the Chesapeake Bay. Habitat complexity and associated benthic communities of experimental triploid Crassostrea virginica and Crassostrea ariakensis reefs were investigated at 4 sites of varying salinity, tidal regime, water depth, predation intensity, and disease pressure in the Chesapeake Bay region (Maryland and Virginia). Four experimental treatments were established at each site: C. virginica, C. ariakensis, 50:50 of C. virginica and C. ariakensis, and shell only. Abundance, biomass, species richness, evenness, dominance, and diversity of reef-associated fauna ...


Oyster (Crassostrea Virginica, Gmelin 1791) Population Dynamics On Public Reefs In The Great Wicomico River, Virginia, Usa, Melissa Southworth, Juliana M. Harding, James A. Wesson, Roger L. Mann 2010 Virginia Institute of Marine Science

Oyster (Crassostrea Virginica, Gmelin 1791) Population Dynamics On Public Reefs In The Great Wicomico River, Virginia, Usa, Melissa Southworth, Juliana M. Harding, James A. Wesson, Roger L. Mann

VIMS Articles

We describe oyster population trends in the Great Wicomico River, VA, from 2000 through 2009 using quantitative fishery independent survey data collected using a stratified random design. The seven public reefs examined cover a total of 2.8 X 10(5) m(2) and vary in individual size from 1.36 X 10(4) to 7.16 X 10(4) m(2). The river is functionally divided by a sand spit into upriver and downriver regions. Oyster densities on the upriver reefs were typically an order of magnitude higher than densities on the downriver reefs within the same time period ...


Oceanic Heterotrophic Bacterial Nutrition By Semilabile Dom As Revealed By Data Assimilative Modeling, YW Luo, MAM Friedrichs, SC Doney, MJ Church, HW Ducklow 2010 Virginia Institute of Marine Science

Oceanic Heterotrophic Bacterial Nutrition By Semilabile Dom As Revealed By Data Assimilative Modeling, Yw Luo, Mam Friedrichs, Sc Doney, Mj Church, Hw Ducklow

VIMS Articles

Previous studies have focused on the role of labile dissolved organic matter (DOM) (defined as turnover time of similar to 1 d) in supporting heterotrophic bacterial production, but have mostly neglected semilabile DOM (defined as turnover time of similar to 100 to 1000 d) as a potential substrate for heterotrophic bacterial growth. To test the hypothesis that semilabile DOM supports substantial amounts of heterotrophic bacterial production in the open ocean, we constructed a 1-dimensional epipelagic ecosystem model and applied it to 3 open ocean sites: the Arabian Sea, Equatorial Pacific and Station ALOHA in the North Pacific Subtropical Gyre. The ...


Net Removal Of Nitrogen Through Ingestion Of Phytoplankton By Atlantic Menhaden Brevoortia Tyrannus In Chesapeake Bay, PD Lynch, MJ Brush, ED Condon, RJ Latour 2010 Virginia Institute of Marine Science

Net Removal Of Nitrogen Through Ingestion Of Phytoplankton By Atlantic Menhaden Brevoortia Tyrannus In Chesapeake Bay, Pd Lynch, Mj Brush, Ed Condon, Rj Latour

VIMS Articles

As filter-feeding planktivores, Atlantic menhaden Brevoortia tyrannus have the potential to influence water quality through ingestion of phytoplankton and assimilation of resultant nutrients. To evaluate the influence of young-of-the-year (YOY) and age-1+ menhaden in Chesapeake Bay, rates of phytoplankton (chl a) ingestion and total dissolved nitrogen (TDN) excretion were measured experimentally across varying phytoplankton concentrations. Ingestion rates of YOY menhaden increased (0.03 to 3.85 µg chl a fish–1 min–1) in response to increasing phytoplankton concentration (4.98 to 198.22 µg chl a l–1), while age-1+ menhaden exhibited virtually no ingestion of the phytoplankton offered ...


Primary Gamma-Herpesviral Infection In Zambian Children, Veenu Minhas, Brad P, Brayfield, Kay L. Crabtree, Chipepo Kankasa, Charles D. Mitchell, Charles Wood 2010 University of Nebraska-Lincoln

Primary Gamma-Herpesviral Infection In Zambian Children, Veenu Minhas, Brad P, Brayfield, Kay L. Crabtree, Chipepo Kankasa, Charles D. Mitchell, Charles Wood

Virology Papers

Background: HHV-8 is closely related to Epstein-Barr virus (EBV), but the clinical presentations of these two infections in early childhood are not well understood. Also, it is not known whether infection by one virus correlates with another. Here, we compare the natural history of infection by these two viruses along with the clinical manifestations and risk factors that are associated with early childhood infection in Zambia, which is an endemic area for HHV-8.

Methods: This study was conducted in a cohort of 12 month old Zambian children (N = 677). Data on socio-economic status and a wide range of clinical manifestations ...


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