Life Sciences Commons^™

Limitation Of Algal Growth By Iron Deficiency In The Australian Subantarctic Region, Peter N. Sedwick, Giacomo R. Ditullio, David A. Hutchins, Philip W. Boyd, F. Brian Griffiths, A. Clive Crossley, Thomas W. Trull, Bernard Queguiner

OES Faculty Publications

In March 1998 we measured iron in the upper water column and conducted iron- and nutrient-enrichment bottle-incubation experiments in the open-ocean Subantarctic region southwest of Tasmania, Australia. In the Subtropical Convergence Zone (∼42°S, 142°E), silicic acid concentrations were low (< 1.5μM) in the upper water column, whereas pronounced vertical gradients in dissolved iron concentration (0.12-0.84 nM) were observed., presumably reflecting the interleaving of Subtropical and Subantarctic waters, and mineral aerosol input. Results of a bottle-incubation experiment performed at this location indicate that phytoplankton growth rates were limited by iron deficiency within the iron-poor layer of the euphotic zone. In the Subantarctic water mass (∼46.8°S, 142°E), low concentrations of dissolved iron (0.05-0.11nM) and silicic acid (< 1μM) were measured throughout the upper water column, and our experimental results indicate that algal growth was limited by iron deficiency. These observations suggest that availability of dissolved iron is a primary factor limiting phytoplankton growth over much of the Subantarctic Southern Ocean in the late summer and autumn.

Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church

Dissertations, Theses, and Masters Projects

No abstract provided.

Spatial And Temporal Distributions Of Organic Matter And Polycyclic Aromatic Hydrocarbons (Pahs) In Surface Waters Of The York River, Va Estuary, Rebecca E. Countway

Dissertations, Theses, and Masters Projects

No abstract provided.

Molecular Phylogeny Of Lake Baikal Amphipods, Kenneth S. Macdonald

Dissertations, Theses, and Masters Projects

No abstract provided.

The Crest, Winter 1999, Virginia Institute Of Marine Science

Reports

Table of Contents:

• Experimental Fishery on Georges Bank Holds Promise for the Scallop Industry
• New VIMS Center Boosts Aquafarming
• Invader Threatens Stressed Ecosystem (Rapa Whelk)
• Microscopic Phytoplankton Live Large
• Reality By the Numbers (Computer Modeling)
• Tautog Research
• Latest Returns From the Game Fish Tagging Program
• Educational Landscape Center (VIMS Teaching Marsh)
• Responding to the Chesapeake Executive Council Directive for Wetlands Protection and Restoration Goals
• Dangers to Blue Crabs Accelerating

Virginia Game Fish Tagging Program Annual Report 1998, John A. Lucy, C.M. Bain, M. D. Arendt

Reports

The Virginia Game Fish Tagging Program (VGFTP), a cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), set records for fish tagged and fish recaptured during 1998, its fourth year of operation.

Investigating The Allosteric Behavior Of Malate Dehydrogenase From Escherichia Coli, Eman M. Ghanem

Masters Theses

Regulatory mechanisms of malate dehydrogenase from E.coli (eMDH) involving NADH as an allosteric effector were investigated. The reaction was studied in both directions: malate oxidation and oxaloacetate reduction. When malate was the variable substrate, a plot of rate against substrate concentration was sigmoidal in the presence of 0.065 mM NADH, which indicates the presence of an allosteric site for NADH on the enzyme. Binding of NADH at the allosteric site causes conformational changes in the active site and, thereby, changes the catalytic activity of the enzyme. An increase in K_m value, from 1.3 to 3.9 mM malate was observed, …

Trans-Resveratrol Inhibits Calcium Influx In Thrombin-Stimulated Human Platelets, Yuliya Dobrydneva, Roy L. Williams, Peter F. Blackmore

Chemistry & Biochemistry Faculty Publications

1 The phytoestrogenic compound trans-resveratrol (trans-3,5,4'-trihydroxystilbene) is found in appreciable quantities in grape skins and wine. It has been shown that both products rich in trans-resveratrol and pure trans-resveratrol inhibit platelet aggregation both in vivo and in vitro. However the mechanism of this action still remains unknown.

2 An essential component of the aggregation process in platelets is an increase in intracellular free Ca²⁺ ([Ca²⁺]_i). Ca²⁺ must enter the cell from the external media through specific and tightly regulated Ca²⁺ channels in the plasma membrane. The objective …

Salinity And Hydrology Of The Fence Road Catchment : A Focus Catchment Of The Blackwood Basin, Ben Whitfield

Resource management technical reports

It is the clearing of native vegetation and replacement with lower water-use annual crops and pastures that is responsible for the developing salinity problem. Traditional farming practices have led to increased recharge to the groundwater systems resulting in increased storage and/or greater areas or rates of discharge. Groundwater monitoring has revealed variable rates of rise throughout the Fence Road catchment, from static to 0.6 metres per year, in a period of average to below average rainfall.

Graded Functional Activation In The Visuo-Spatial System With The Amount Of Task Demand, Patricia Carpenter, Marcel Just, Timothy Keller, William Eddy, Keith Thulborn

Marcel Adam Just

No abstract provided.

Time Course Of Fmri-Activation In Language And Spatial Networks During Sentence Comprehension, Patricia A. Carpenter, Marcel Adam Just, Timothy A. Keller, William F. Eddy, Keith R. Thulborn

Marcel Adam Just

No abstract provided.

Plasticity Of Language-Related Brain Function During Recovery From Strok, Keith R. Thulborn, Patricia A. Carpenter, Marcel Adam Just

Marcel Adam Just

No abstract provided.

Computational Modeling Of High-Level Cognition And Brain Function, Marcel Adam Just, Patricia A. Carpenter, Sashank Varma

Marcel Adam Just

No abstract provided.