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Full-Text Articles in Life Sciences
Topographic Effects On The Path And Evolution Of Loop Current Eddies, Kyung Hoon Hyun, Patrick J. Hogan
Topographic Effects On The Path And Evolution Of Loop Current Eddies, Kyung Hoon Hyun, Patrick J. Hogan
Faculty Publications
Eddy-topography (ET) interactions are important in determining the path and evolution of oceanic eddies, including Loop Current Eddies (LCE) in the Gulf of Mexico (GOM). We use the Hybrid Coordinate Ocean Model and satellite altimetry data to investigate the ET interactions and the impact on LCE pathway evolution in the GOM. Satellite altimetry reveals that LCEs translate dominantly westward in the central GOM and strongly collide and reflect against topography near the continental slope in the northern and western GOM. The result is the frequent generation of an anticyclone-cyclone (AC) pair in conjunction with the LCEs. In the absence of …
Leucon (Crymoleucon) Rossi, A New Species (Crustacea: Cumacea: Leuconidae) From The Shelf Waters Of The Ross Sea (Antarctica), With A Key To The Genus Leucon South Of 60°S, Peter Rehm, Richard W. Heard
Leucon (Crymoleucon) Rossi, A New Species (Crustacea: Cumacea: Leuconidae) From The Shelf Waters Of The Ross Sea (Antarctica), With A Key To The Genus Leucon South Of 60°S, Peter Rehm, Richard W. Heard
Faculty Publications
A new leuconid cumacean, Leucon (Crymoleucon) rossi n. sp., is described from depths of 84 to 458 m in the Ross Sea off the Victoria Land coast. Leucon rossi n. sp. is distinguished from other members of the genus by a combination of characters including 1) a blunt, horizontally directed pseudorostrum) Without a distinctly protruding siphon; 2) strongly developed antennal notch; 3) entire dorsomedian margin of carapace appearing serrate, armed with 14 to 19 anteriorly Curved spines in female (up to 21 in subadult males); 4) a small, but distinct, spine behind the frontal lobe; and 5) the uropodal peduncle …
A Competitive Hybridization Model Predicts Probe Signal Intensity On High Density Dna Microarrays, Shuzhao Li, Alex Pozhitkov, Marius Brouwer
A Competitive Hybridization Model Predicts Probe Signal Intensity On High Density Dna Microarrays, Shuzhao Li, Alex Pozhitkov, Marius Brouwer
Faculty Publications
A central, unresolved problem of DNA microarray technology is the interpretation of different signal intensities from multiple probes targeting the same transcript. We propose a competitive hybridization model for DNA microarray hybridization. Our model uses a probe-specific dissociation constant that is computed with current nearest neighbor model and existing parameters, and only four global parameters that are fitted to Affymetrix Latin Square data. This model can successfully predict signal intensities of individual probes, therefore makes it possible to quantify the absolute concentration of targets. Our results offer critical insights into the design and data interpretation of DNA microarrays.
Seasonal Variations In Nutrient Concentrations And Speciation In The Chena River, Alaska, Yihua Cai, Laodong Guo, Thomas A. Douglas, Terry E. Whitledge
Seasonal Variations In Nutrient Concentrations And Speciation In The Chena River, Alaska, Yihua Cai, Laodong Guo, Thomas A. Douglas, Terry E. Whitledge
Faculty Publications
To better understand the seasonal controls on nutrient abundances, speciation, and fluxes in a watershed underlain by discontinuous permafrost, we collected water samples biweekly from the Chena River during 2005-2006 to measure inorganic and organic N, P, and Si in dissolved and particulate phases. Nitrate concentrations were low (8-14 mu M) during the winter and summer dry seasons but were elevated during the spring freshet (15-24 mu M). Ammonium varied from 8 to 13 mu M during the winter but dropped dramatically during the ice-open season to 0.1-3 mM. Phosphate was very low throughout the year (ranging from 0.03 to …
Satellite Assessment Of Bio-Optical Properties Of Northern Gulf Of Mexico Coastal Waters Following Hurricanes Katrina And Rita, Steven E. Lohrenz, Wei-Jun Cai, Xiaogang Chen, Merritt Tuel
Satellite Assessment Of Bio-Optical Properties Of Northern Gulf Of Mexico Coastal Waters Following Hurricanes Katrina And Rita, Steven E. Lohrenz, Wei-Jun Cai, Xiaogang Chen, Merritt Tuel
Faculty Publications
The impacts of major tropical storms events on coastal waters include sediment resuspension, intense water column mixing, and increased delivery of terrestrial materials into coastal waters. We examined satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) ocean color sensor aboard the Aqua spacecraft following two major hurricane events: Hurricane Katrina, which made landfall on 29 August 2005, and Hurricane Rita, which made landfall on 24 September. MODIS Aqua true color imagery revealed high turbidity levels in shelf waters immediately following the storms indicative of intense resuspension. However, imagery following the landfall of Katrina showed relatively rapid return of …
Pan-Arctic Patterns In Black Carbon Sources And Fluvial Discharges Deduced From Radiocarbon And Pah Source Apportionment Markers In Estuarine Surface Sediments, Marie Elmquist, Igor Semiletov, Laodong Guo, Örjan Gustafsson
Pan-Arctic Patterns In Black Carbon Sources And Fluvial Discharges Deduced From Radiocarbon And Pah Source Apportionment Markers In Estuarine Surface Sediments, Marie Elmquist, Igor Semiletov, Laodong Guo, Örjan Gustafsson
Faculty Publications
A pan-arctic geospatial picture of black carbon (BC) characteristics was obtained from the seven largest arctic rivers by combining with molecular combustion markers (polycyclic aromatic hydrocarbons) and radiocarbon ((14)C) analysis. The results suggested that the contribution from modern biomass burning to BC ranged from low in the Yukon (8%) and Lena (5%) Rivers to high in the Yenisey River (88%). The Mackenzie River contributed almost half of the total arctic fluvial BC export of 202 kton a(-1) (kton = 10(9) g), with the five Russian-Arctic rivers contributing 10-36 kton a(-1) each. The (14)C-based source estimate of fluvially exported BC to …
Hurricane Katrina Winds Measured By A Buoy-Mounted Sonic Anemometer, Stephan D. Howden, David Gilhousen, Norman Guinasso, John Walpert, Michael Sturgeon, Les Bender
Hurricane Katrina Winds Measured By A Buoy-Mounted Sonic Anemometer, Stephan D. Howden, David Gilhousen, Norman Guinasso, John Walpert, Michael Sturgeon, Les Bender
Faculty Publications
The eye of Hurricane Katrina passed within 49 n mi of an oceanographic observing system buoy in the Mississippi Bight that is part of the Central Gulf of Mexico Ocean Observing System. Although a mechanical anemometer failed on the buoy during the hurricane, a two-axis sonic anemometer survived and provided a complete record of the hurricane's passage. This is the first reported case of a sonic anemometer surviving a hurricane and reporting validated data, and it demonstrates that this type of anemometer is a viable alternative to the mechanical anemometers traditionally used in marine applications. The buoy pitch and roll …
Seasonal Variability Of The Observed Barrier Layer In The Arabian Sea, Pankajakshan Thadathil, Prasad Thoppil, R.R. Pao, P.M. Muraleedharan, Y.K. Somayajulu, V.V. Gopalakrishna, Raghu Murtugudde, G.V. Reddy, C. Revichandran
Seasonal Variability Of The Observed Barrier Layer In The Arabian Sea, Pankajakshan Thadathil, Prasad Thoppil, R.R. Pao, P.M. Muraleedharan, Y.K. Somayajulu, V.V. Gopalakrishna, Raghu Murtugudde, G.V. Reddy, C. Revichandran
Faculty Publications
The formation mechanisms of the barrier layer ( BL) and its seasonal variability in the Arabian Sea ( AS) are studied using a comprehensive dataset of temperature and salinity profiles from Argo and other archives for the AS. Relatively thick BL of 20-60 m with large spatial extent is found in the central-southwestern AS ( CSWAS), the convergence zone of the monsoon wind, during the peak summer monsoon ( July-August) and in the southeastern AS ( SEAS) and northeastern AS ( NEAS) during the winter ( January-February). Although the BL in the SEAS has been reported before, the observed thick …
Comment On "How Accurate Are (234)Th Measurements In Seawater Based On The Mno(2)-Impregnated Cartridge Technique?'' By Pinghe Cai Et Al., Chin-Chang Hung, S. Bradley Moran, J. Kirk Cochran, Laodong Guo, Laodong Guo, Peter H. Santschi
Comment On "How Accurate Are (234)Th Measurements In Seawater Based On The Mno(2)-Impregnated Cartridge Technique?'' By Pinghe Cai Et Al., Chin-Chang Hung, S. Bradley Moran, J. Kirk Cochran, Laodong Guo, Laodong Guo, Peter H. Santschi
Faculty Publications
No abstract provided.
Effects Of Cyclic Hypoxia On Gene Expression And Reproduction In A Grass Shrimp, Palaemonetes Pugio, Nancy J. Brown-Peterson, C. Steve Manning, Vishal Patel, Nancy D. Denslow, Marius Brouwer
Effects Of Cyclic Hypoxia On Gene Expression And Reproduction In A Grass Shrimp, Palaemonetes Pugio, Nancy J. Brown-Peterson, C. Steve Manning, Vishal Patel, Nancy D. Denslow, Marius Brouwer
Faculty Publications
Cyclic changes in dissolved oxygen occur naturally in shallow estuarine systems, yet little is known about the adaptations and responses of estuarine organisms to cyclic hypoxia. Here we examine the responses of Palaemonetes pugio, a species of grass shrimp, to cyclic hypoxia (1.5-8 mg/l dissolved oxygen; 4.20-22.42 kPa) at both the molecular and organismal levels. We measured alterations in gene expression in hepatopancreas tissue of female grass shrimp using custom cDNA macroarrays. After short-term (3-d) exposure to cyclic hypoxia, mitochondrial manganese superoxide dismutase (MnSOD) was upregulated and 70-kd heat shock proteins (HSP70) were downregulated. After 7-d exposure, nuclear genes encoding …