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Marine Biology

2014

Articles 1 - 30 of 36

Full-Text Articles in Earth Sciences

Aptian To Santonian Foraminiferal Biostratigraphy And Paleoenvironmental Change In The Sverdrup Basin As Revealed At Glacier Fiord, Axel Heiberg Island, Canadian Arctic Archipelago, Claudia J. Schröder-Adams, Jens O. Herrle, Ashton F. Embry, James W. Haggart, Jennifer M. Galloway, Adam T. Pugh, David M. Harwood Nov 2014

Aptian To Santonian Foraminiferal Biostratigraphy And Paleoenvironmental Change In The Sverdrup Basin As Revealed At Glacier Fiord, Axel Heiberg Island, Canadian Arctic Archipelago, Claudia J. Schröder-Adams, Jens O. Herrle, Ashton F. Embry, James W. Haggart, Jennifer M. Galloway, Adam T. Pugh, David M. Harwood

ANDRILL Research and Publications

Exceptional exposures of a High Arctic Cretaceous sedimentary record were studied at Glacier Fiord, Axel Heiberg Island. The succession reveals a complex Aptian to Santonian paleoenvironmental history of the Sverdrup Basin that documents several global events. Foraminiferal faunas in combination with rare macrofossil occurrences permit the distinction of nine zones that facilitate biostratigraphic correlations to other High Arctic locales, the Beaufort Mackenzie Basin and the Western Interior Sea. The depositional environment as exposed in the Christopher, Hassel, Bastion Ridge and Kanguk formations changed frequently from a shelf to a shoreface setting. Most sequence boundaries appear to be conformable where shoaling …


Iron Sources And Dissolved-Particulate Interactions In The Seawater Of The Western Equatorial Pacific, Iron Isotope Perspectives, M. Labatut, F. Lacan, C. Pradoux, J. Chmeleff, A. Radic, J. W. Murray, F. Poitrasson, Anne M. Johansen, F. Thil Oct 2014

Iron Sources And Dissolved-Particulate Interactions In The Seawater Of The Western Equatorial Pacific, Iron Isotope Perspectives, M. Labatut, F. Lacan, C. Pradoux, J. Chmeleff, A. Radic, J. W. Murray, F. Poitrasson, Anne M. Johansen, F. Thil

All Faculty Scholarship for the College of the Sciences

This work presents iron isotope data in the western equatorial Pacific. Marine aerosols and top core margin sediments display a slightly heavy Fe isotopic composition (δ56Fe) of 0.33 ± 0.11‰ (2SD) and 0.14 ± 0.07‰, respectively. Samples reflecting the influence of Papua New Guinea runoff (Sepik River and Rabaul volcano water) are characterized by crustal values. In seawater, Fe is mainly supplied in the particulate form and is found with a δ56Fe between −0.49 and 0.34 ± 0.07‰. The particulate Fe seems to be brought mainly by runoff and transported across continental shelves and slopes. …


First Record Of The Tropical House Gecko Hemidactylus Mabouia (Moreau De Jonnès, 1818) In Texas, Alejandro Fierro-Cabo, August Rentfro Oct 2014

First Record Of The Tropical House Gecko Hemidactylus Mabouia (Moreau De Jonnès, 1818) In Texas, Alejandro Fierro-Cabo, August Rentfro

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Invasions of the tropical house gecko Hemidactylus mabouia (Moreau de Jonnes, 1818) in the tropical Americas are well documented. While this gecko has been reported as well established and expanding its range in Florida, here we document the first record in the United States outside of this state. We detected a small reproducing population in Cameron County, Brownsville, Texas. We expect a rapid colonization of buildings by this species in southern Texas. We consider that this potential invasion poses novel obstacles to the continued presence of the earlier invasive Mediterranean gecko Hemidactylus turcicus (Linnaeus, 1758) across Texas


Cruise: Yr080507, Stations: S4526- S4540, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080507, Stations: S4526- S4540, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080416, Stations: S4489- S4497, Gloucester Point, York River Virginia 5-Hour Mudbed Calibration Survey Bracketing An Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080416, Stations: S4489- S4497, Gloucester Point, York River Virginia 5-Hour Mudbed Calibration Survey Bracketing An Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 5-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080415, Stations: S4461- S4488, Clay Bank, York River Virginia 6-Hour Mudbed Calibration Survey Bracketing An Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080415, Stations: S4461- S4488, Clay Bank, York River Virginia 6-Hour Mudbed Calibration Survey Bracketing An Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 6-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080418, Stations: S4498- S4514, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080418, Stations: S4498- S4514, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Ebb Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080505, Stations: S4515- S4525, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080505, Stations: S4515- S4525, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080515, Stations: S4565- S4591, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080515, Stations: S4565- S4591, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080606, Stations: S4602- S4620, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080606, Stations: S4602- S4620, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080609, Stations: S4621- S4635, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080609, Stations: S4621- S4635, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080603, Stations: S4582- S4601, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080603, Stations: S4582- S4601, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst data and bottom burst data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Cruise: Yr080514, Stations: S4541- S4564, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs Aug 2014

Cruise: Yr080514, Stations: S4541- S4564, Clay Bank, York River Virginia 3-Hour Mudbed Calibration Survey From A Slack To Flood Tide, Grace M. Cartwright, Carl T. Friedrichs

Data

Dataset consists of profile and water column burst Data and bottom burst Data collected as part of a 3-hour anchor station survey in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Microstratigraphic Analysis Of Burrow-Reworked Dinosaur Track Bed At Joanna's Track Site, Cretaceous Glen Rose Formation, Glen Rose, Texas, Michael Blair, Benjamin Dattilo, Anthony Martin, James Farlow Jul 2014

Microstratigraphic Analysis Of Burrow-Reworked Dinosaur Track Bed At Joanna's Track Site, Cretaceous Glen Rose Formation, Glen Rose, Texas, Michael Blair, Benjamin Dattilo, Anthony Martin, James Farlow

Benjamin F. Dattilo

Although dinosaur trackways are common in the Cretaceous Glen Rose Formation of Texas, the recently discovered Joanna track site illustrates a unique ichnological relationship where dinosaur tracks were disrupted by invertebrate burrows made long after burial. In an effort to document the precise sequence of events, we described the interval from 0.3 m below the track layer through 2.7 m above it in a vertical outcrop adjacent to the track site, focusing on the 70-cm of strata immediately above the track horizon. An 8-meter N-S cross-section of this 70-cm interval was power-washed, examined for trace fossils, body fossils, and lithology …


Push Me – Pull You: Experimental Biomechanics Of Immobile Suspension Feeders On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Joshua Corrie, Daniel Piquard, Jennifer Bauer Jul 2014

Push Me – Pull You: Experimental Biomechanics Of Immobile Suspension Feeders On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Joshua Corrie, Daniel Piquard, Jennifer Bauer

Benjamin F. Dattilo

Immobile suspension feeders on soft substrates (ISOSS; Thayer 1979) although rare in modern marine habitats, were relatively common in the Paleozoic. Numerous Paleozoic taxa have been interpreted as dwelling on soft unconsolidated sediments and possessing morphologic features that either anchor them to the sea floor (e.g., crinoid holdfasts) or prevent them from sinking in (strophomenid brachiopods). Thayer (1975) reviewed the morphologic adaptations for forms living on soft-muddy bottoms and provided a quantitative expression of the static stresses involved. The same quantitative expression can also be used to describe the forces involved in anchoring. With the exception of Leighton and Savarese …


An Unusual Association Of Pseudolingula And Rafinesquina From The Upper Ordovician Of Ohio, Benjamin Dattilo, Rebecca Freeman, Bryan Utesch, Steve Felton, John Pojeta Jul 2014

An Unusual Association Of Pseudolingula And Rafinesquina From The Upper Ordovician Of Ohio, Benjamin Dattilo, Rebecca Freeman, Bryan Utesch, Steve Felton, John Pojeta

Benjamin F. Dattilo

Late Ordovician members of Order Lingulida, for the most part, resemble modern lingulids in their infaunal habits and marginal habitats. Pseudolingula, a common Cincinnatian form, is often found preserved in burrows in life position, and as such, it could probably escape moderate sediment accumulations. An unusual association of thousands of specimens of the lingulate Pseudolingula and hundreds of the strophomenid Rafinesquina in the Upper Ordovician of the Cincinnati, Ohio region presents an interesting case. This association occurs on 4-square-meter exposure of a 10 cm shell bed in the Fairview Formation at Harsha Lake, Ohio. The bed is covered with Rafinesquina …


What Can We Learn From Confusing Olivella Columellaris And O. Semistriata (Olivellidae, Gastropoda), Two Key Species In Panamic Sandy Beach Ecosystems?, Allison I. Troost, Samantha D. Rupert, Ariel Z. Cyrus, Frank V. Paladino, Benjamin F. Dattilo, Winfried S. Peters Jul 2014

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata (Olivellidae, Gastropoda), Two Key Species In Panamic Sandy Beach Ecosystems?, Allison I. Troost, Samantha D. Rupert, Ariel Z. Cyrus, Frank V. Paladino, Benjamin F. Dattilo, Winfried S. Peters

Benjamin F. Dattilo

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension-feeding, swash-surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and museum collections, …


The Curse Of Rafinesquina: Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian (Katian, Ordovician) Series Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta Jul 2014

The Curse Of Rafinesquina: Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian (Katian, Ordovician) Series Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta

Benjamin F. Dattilo

Thousands of lingulid brachiopods were found clustered beneath hundreds of individual valves of the strophomenid brachiopod Rafinesquina in the Upper Ordovician of Ohio. This association suggested a relationship between the two brachiopods, but the nature of this relationship was unclear. We utilized serial thin sectioning to examine these brachiopods and to determine the origin of the bed in which they were found. Sedimentary structures, mixed taphonomies, and stratigraphic and paleogeographic setting suggest that the lingulids occupied a hiatal concentration that had previously been reworked, but not significantly transported, by tropical storms. The final burial event was a storm that exhumed …


The “Passive Implanter” Strategy Of The Adult Ordovician Brachiopod, Platystrophia Ponderosa., Sadye Howald, Benjamin Dattilo Jul 2014

The “Passive Implanter” Strategy Of The Adult Ordovician Brachiopod, Platystrophia Ponderosa., Sadye Howald, Benjamin Dattilo

Benjamin F. Dattilo

Platystrophia ponderosa is found throughout the Maysvillian Strata of the Cincinnati Ordovician. This species thrived in a high energy environment with only muddy shell gravels, and no solid substrates for pedicle attachment. Our growth-series studies show juveniles of this species had large pedicle openings, thin shell, small size, nearly flat shape, and shallow sinus/sulcus. In contrast, the adults had relatively small pedicle openings obstructed by a large beak, secondary thickening of the pedicle valve making it considerably thicker than the brachial valve, large size (up to 4cm in diameter), spherical shape, and deep sinus/sulcus. The morphological characteristics of the adult …


How Many Track Horizons Are Exposed At Dinosaur Valley State Park? Stratigraphy Of The Cretaceous Glen Rose Formation Track Sites Of The Paluxy River, Glen Rose, Texas, Benjamin Dattilo, Sadye Howald, James Farlow, Anthony Martin Jul 2014

How Many Track Horizons Are Exposed At Dinosaur Valley State Park? Stratigraphy Of The Cretaceous Glen Rose Formation Track Sites Of The Paluxy River, Glen Rose, Texas, Benjamin Dattilo, Sadye Howald, James Farlow, Anthony Martin

Benjamin F. Dattilo

The dinosaur tracks of the Glen Rose Formation in the Paluxy River at Dinosaur Valley State Park are among the best preserved and most abundant in the world. While many track sites are easily correlated to the Main Tracksite, others, especially those at the extreme ends of the park, are differently preserved and not obviously correlated. To count track horizons, several stratigraphic sections were measured along the river from upstream at the McFall Ledge Site to 7.6 km downstream at the County Road 1001 crossing (3.1 km linear distance). These reveal 6 meters of strata separating two track-bearing horizons exposed …


Stop Clinging! –How The Ordovician Brachiopod (Fka Platystrophia) Vinlandostrophia Ponderosa Outgrew Its Mid-Life Attachment Crisis, Benjamin Dattilo, Sadye Howald Jul 2014

Stop Clinging! –How The Ordovician Brachiopod (Fka Platystrophia) Vinlandostrophia Ponderosa Outgrew Its Mid-Life Attachment Crisis, Benjamin Dattilo, Sadye Howald

Benjamin F. Dattilo

The high-energy nearshore environment and muddy shifting shell gravels recorded in Maysvillian strata of the Cincinnati Ordovician might seem particularly inhospitable to brachiopods, which generally require solid surfaces for attachment. Nevertheless, Vinlandostrophia ponderosa thrived and even characterizes these facies. A preliminary study of growth series suggests that, like the full-grown stages of related species, smaller V. ponderosa were attached by pedicle. Smaller specimens have a large pedicle opening, a nearly flat shape, thin shell, and a shallow sinus/sulcus, leaving the commissure nearly flat. These characteristics are consistent with strong, erect pedicle attachment, even stronger than found in related species, whose …


The Orientation Of Strophomenid Brachiopods On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Daniel Piquard, Jennifer Bauer, Joshua Corrie Jul 2014

The Orientation Of Strophomenid Brachiopods On Soft Substrates, Roy Plotnick, Benjamin Dattilo, Daniel Piquard, Jennifer Bauer, Joshua Corrie

Benjamin F. Dattilo

Strophomenid brachiopods have long been interpreted as ‘‘snowshoe’’ strategists, with their flattened concavoconvex valves providing resistance to foundering in very soft sediments. There has been a sharp difference of opinion in whether the shells were oriented with their convex or their concave surface in contact with the sediment. This study, along with independent evidence from sedimentology, ichnology, and morphology, indicates that the strophomenids lived with their shells concave down (convex up). Experiments indicate the force required to push shells into soft cohesive muds is much greater for the convex up than for the convex down orientation. Forces also increase with …


Gape, Feeding Currents And Valve Snapping In Thecidellina Meyeri From Curaçao, Netherlands Antilles: Biomechanical Analogue For Trace-Making Paleozoic Strophomenates?, Benjamin Dattilo, Tanya Del Valle, David Meyer, Aaron Morse Jul 2014

Gape, Feeding Currents And Valve Snapping In Thecidellina Meyeri From Curaçao, Netherlands Antilles: Biomechanical Analogue For Trace-Making Paleozoic Strophomenates?, Benjamin Dattilo, Tanya Del Valle, David Meyer, Aaron Morse

Benjamin F. Dattilo

The ability of Ordovician strophomenates Sowerbyella and Rafinesquina to move sediment and create moat-like depressions has led to questions about mechanisms. Anatomical studies suggest a gape of more than 45°, likely critical to trace-making abilities. Strophomenates are extinct, but thecidellinids are reasonably good analogues; they also gape widely and have a similar lophophore structure. They differ in their small size, 3 - 5 mm, lack of concavo-convex form, and by pedicle valve cementation. Nevertheless, their physiology could illuminate biomechanical constraints on strophomenate-sediment interactions. For this study, we analyzed 1 hour of video showing 30+ specimens collected with the fragment of …


The Brachiopod Trap: What Their Oldest (Upper Ordovician, Ohio) Failed Escape Burrows Tell Us About The Evolution Of Burrowing In Lingulids, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Bryan Utesch, Steve Felton, John Pojeta Jul 2014

The Brachiopod Trap: What Their Oldest (Upper Ordovician, Ohio) Failed Escape Burrows Tell Us About The Evolution Of Burrowing In Lingulids, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Bryan Utesch, Steve Felton, John Pojeta

Benjamin F. Dattilo

Infaunal organisms living in shallow marine settings are vulnerable to exhumation during storms or entombment by storm-deposited sediments. Cambrian­–Early Ordovician lingulids included epifaunal as well as possible infaunal forms. However, many epifaunal forms became extinct during the Middle Ordovician, and Late Ordovician lingulids were similar in their infaunal habits and marginal habitats. Modern infaunal lingulids are able to reorient themselves after burial in sediments, but it is unclear when this ability evolved. Initial burrowing of juvenile lingulids, as well as re-burrowing of exhumed modern lingulids involves digging downwards and then back up in a u-shape, but successful escape burrowing involves …


Turbidimetric Determination Of Anionic Polyacrylamide In Low Carbon Soil Extracts, Jihoon Kang, Tyler D. Sowers, Owen W. Duckworth, Aziz Amoozegar, Joshua L. Heitman, Richard A. Mclaughlin Jun 2014

Turbidimetric Determination Of Anionic Polyacrylamide In Low Carbon Soil Extracts, Jihoon Kang, Tyler D. Sowers, Owen W. Duckworth, Aziz Amoozegar, Joshua L. Heitman, Richard A. Mclaughlin

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Concerns over runoff water quality from agricultural lands and construction sites have led to the development of improved erosion control practices, including application of polyacrylamide (PAM). We developed a quick and reliable method for quantifying PAM in soil extracts at low carbon content by using a turbidimetric reagent, Hyamine 1622. Three high-molecular weight anionic PAMs differing in charge density (7, 20, and 50 mol%) and five water matrices, deionized (DI) water and extracts from four different soils, were used to construct PAM calibration curves by reacting PAM solutions with hyamine and measuring turbidity development from the PAM–hyamine complex. The PAM …


Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker May 2014

Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker

2014 Student Theses

Over three million people call Long Island their home. With access to beautiful landscapes, world-renowned beaches, and proximity to New York City, it is no wonder that so many proudly call this geographic stretch of glacial till their home. However, throughout the years our actions do not necessarily reflect this affection we have to our home. Years of sprawl and human infestation across the island have resulted in widespread environmental degradation. Specifically, the water we drink and the beaches we enjoy have become endangered. I plan on studying the urban ecology of how intensified population growth led to the eutrophication …


Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas May 2014

Restoration Of Tryptophan Hydroxylase Functions And Serotonin Content In The Atlantic Croaker Hypothalamus By Antioxidant Treatment During Hypoxic Stress, Md. Saydur Rahman, Peter Thomas

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH) and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT) and its precursor, 5-hydroxytryptophan (5-HTP) as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions …


Growth And Nitrogen Uptake Kinetics In Cultured Procentrum Donghaiense, Zhangxi Hu, Shunshan Duan, Margaret R. Mulholland Apr 2014

Growth And Nitrogen Uptake Kinetics In Cultured Procentrum Donghaiense, Zhangxi Hu, Shunshan Duan, Margaret R. Mulholland

OES Faculty Publications

We compared growth kinetics of Prorocentrum donghaiense cultures on different nitrogen (N) compounds including nitrate, ammonium urea, glutamic acid, dialanine, and cynate. P. donghaiense exhibited standard Monod-type growth kinetics over a range of nitrogen concentrations for all N. Compounds tested. Cultures grown on glu and urea had the highest maximum growth rates. However, cultures grown on cyanate had lower half saturation constants. Nitrogen uptake kinetics were measured in nitrate-deplete and replete batch cultures of P. donghaiense. In nitrate-deplete batch cultures, P. donghaiense exhibited Michaelis-Menten type uptake kinetics for nitrate, ammonium, urea and algal amino acids; uptake was saturated at …


Influence Of Constant And Periodic Experimental Hypoxic Stress On Atlantic Croaker Otolith Chemistry, John Mohan, Md. Saydur Rahman, Peter Thomas, Benjamin Walther Jan 2014

Influence Of Constant And Periodic Experimental Hypoxic Stress On Atlantic Croaker Otolith Chemistry, John Mohan, Md. Saydur Rahman, Peter Thomas, Benjamin Walther

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The chemical composition of fish otoliths may provide information on the environmental exposure histories of fishes if ‘vital effects’ on element incorporation are minimal. In order to use redox-sensitive geochemical proxies, such as manganese, in otoliths to quantify sublethal exposure to hypoxia, the relative influence of endogenous and exogenous controls on otolith composition must first be validated. Controlled laboratory experiments were conducted on Atlantic croaker Micropogonias undulatus to examine the response of otolith Sr:Ca, Ba:Ca, Mg:Ca, Mn:Ca, and Na:Ca ratios to either constant or periodic hypoxia treatments for 4 and 10 wk, respectively. Although fish somatic growth and condition were …


Rapid Fluctuations In Mid-Latitude Siliceous Plankton Production During The Middle Eocene Climatic Optimum (Odp Site 1051, Western North Atlantic), Jakub Witkowski, Steven M. Bohaty, Kirsty M. Edgar, David M. Harwood Jan 2014

Rapid Fluctuations In Mid-Latitude Siliceous Plankton Production During The Middle Eocene Climatic Optimum (Odp Site 1051, Western North Atlantic), Jakub Witkowski, Steven M. Bohaty, Kirsty M. Edgar, David M. Harwood

ANDRILL Research and Publications

The Middle Eocene Climatic Optimum (MECO; ~ 40 million years ago [Ma]) is one of the most prominent transient global warming events in the Paleogene. Although the event is well documented in geochemical and isotopic proxy records at many locations, the marine biotic response to the MECO remains poorly constrained. We present new high-resolution, quantitative records of siliceous microplankton assemblages from the MECO interval of Ocean Drilling Program (ODP) Site 1051 in the subtropical western North Atlantic Ocean, which are interpreted in the context of published foraminiferal and bulk carbonate stable isotope (δ18O and δ13C) records. …