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A Review Of Polylekithum Arnold, 1934 And Its Familial Affinities Using Morphological And Molecular Data, With Description Of Polylekithum Catahoulensis Sp Nov., Stephen S. Curran, Vasyl V. Tkach, Robin M. Overstreet

Faculty Publications

The type material of Polylekithum ictaluri, P. halli, and Maculifer chandleri was examined from the United States National Parasite Museum, and we determined that the material was conspecific, making P. halli and M. chandleri junior subjective synonyms of P. ictaluri. Polylekithum catahoulensis sp. nov. was described from material collected from catfishes at the Catahoula Wildlife Refuge, LaSalle Parish, Louisiana, USA, and compared with P. ictaluri collected from catfishes in Reelfoot Lake, Obion County, Tennessee, USA, and the Pearl River, Hancock County, Mississippi, USA. Polylekithum catahoulensis had smaller eggs (77–88 μm long by 51–63 μm wide vs. 94–108 μm by …

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Red Tides In The Gulf Of Mexico: Where, When, And Why?, J. J. Walsh, J. K. Jolliff, B. P. Darrow, J. M. Lenes, S.P. Milroy, A. Remsen, D.A. Dieterle, K.L. Carder, F.R. Chen, F.R. Chen, G.A. Vargo, R.H. Weisberg, K.A. Fanning, F.E. Muller-Karger, E. Shinn, K.A. Steidinger, C.A. Heil, C.R. Tomas, J.S. Prospero, T.N. Lee, G.J. Kirkpatrick, T.E. Whitledge, D.A. Stockwell, T.A. Villareal, A.E. Jochens, P.S. Bontempi

Faculty Publications

Independent data from the Gulf of Mexico are used to develop and test the hypothesis that the same sequence of physical and ecological events each year allows the toxic dinoflagellate Karenia brevis to become dominant. A phosphorus-rich nutrient supply initiates phytoplankton succession, once deposition events of Saharan iron-rich dust allow Trichodesmium blooms to utilize ubiquitous dissolved nitrogen gas within otherwise nitrogen-poor sea water. They and the co-occurring K. brevis are positioned within the bottom Ekman layers, as a consequence of their similar diel vertical migration patterns on the middle shelf. Upon onshore upwelling of these near-bottom seed populations to CDOM-rich …

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Effects Of Long-Term Hypoxia On Enzymes Of Carbohydrate Metabolism In The Gulf Killifish, Fundulus Grandis, Mery L. Mártinez, Christie Landry, Ryan Boehm, Steve Manning, Bernard B. Rees

Faculty Publications

The goal of the current study was to generate a comprehensive, multi-tissue perspective of the effects of chronic hypoxic exposure on carbohydrate metabolism in the Gulf killifish Fundulus grandis. Fish were held at approximately 1.3 mg l(-1) dissolved oxygen (similar to 3.6 kPa) for 4 weeks, after which maximal activities were measured for all glycolytic enzymes in four tissues (white skeletal muscle, liver, heart and brain), as well as for enzymes of glycogen metabolism (in muscle and liver) and gluconeogenesis (in liver). The specific activities of enzymes of glycolysis and glycogen metabolism were strongly suppressed by hypoxia in white skeletal …

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Dissolved Gallium In The Northwest Pacific And The South And Central Atlantic Oceans: Implications For Aeolian Fe Input And A Reconsideration Of Profiles, Alan M. Shiller, Gautam Raj Bairamadgi

Faculty Publications

[1] The distribution of dissolved gallium, a less-reactive analogue of aluminum, has the potential to reveal information about the averaged dust input to the surface ocean and to complement studies using aluminum as a tracer. New data are presented here on the distribution of dissolved Ga, including six profiles in the south and central Atlantic as well as seven shallow and two deep profiles from the northwest Pacific. The Atlantic data allow for an estimate of Ga in Antarctic Bottom Water ( similar to 25 - 30 pmol kg(-1)) and show reasonably conservative behavior in deep waters. In the northwest …

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Source And Transport Of Terrigenous Organic Matter In The Upper Yukon River: Evidence From Isotope (𝛿c-13, Δc-14, And 𝛿n-15) Composition Of Dissolved, Colloidal, And Particulate Phases, Laodong Guo, Robie W. Macdonald

Faculty Publications

Natural organic matter was collected from the upper Yukon River and size fractionated into the (LMW-DOC), colloidal (COC, 1 kDa to 0.45 mu m) and particulate organic carbon (POC, > 0.45 mu m) phases for characterization of elemental (C and N) and isotopic (C-13, C-14 and N-15) composition to examine their sources and transport. Concentrations of total organic carbon (TOC) decreased from 3010 mu M in mid-May to 608 mu M in September, accompanying an increase in river water delta O-18 from the snowmelt to summer and early fall. COC was the predominant OC species, comprising, on average, 63 +/- 8% …

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Summer Transport Estimates Of The Kamchatka Current Derived As A Variational Inverse Of Hydrophysical And Surface Drifter Data, G.G. Panteleev, P. Stabeno, V.A. Luchin, Dmitri A. Nechaev, M. Ikeda

Faculty Publications

The quasistationary summer Bering Sea circulation is reconstructed as a variational inverse of the hydrographic and atmospheric climatologies, transport estimates through the Bering Strait, and surface drifter data. Our results indicate the splitting of the Kamchatka Current in the vicinity of the Shirshov Ridge. This branching is in agreement with independent ARGO drifter observations. It was also found, that transport of the Kamchatka Current gradually increases downstream from 14 Sv in the Olyutorsky Gulf to 24 Sv in the Kamchatka Strait, which is twice higher than previous estimates.

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Vittatispora, A New Melanosporaceous Genus From Indian Soil, Preeti Chaudhary, Jinx Campbell, David L. Hawksworth, Kedarnath N. Sastry

Faculty Publications

Vittatispora coorgii gen. sp. nov., isolated from soil in India, is described and illustrated. The fungus has morphological characteristics of the genera Melanospora, Sphaerodes and Syspastospora. The most striking feature is the presence of a thick hyaline ridge along the vertical axis of the lemonshaped ascospores wall. Perithecia also have a long neck composed of adhering hyphae, similar to that of Syspatospora. Phylogenetic studies on the 28S rDNA indicate it is closely related to Melanospora and Sphaerodes and belongs in the Ceratostomataceae. The new genus is based on the distinctive morphology and phylogenetic analyses. The fungus grew in culture only …

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Antiestrogens Inhibit Xenoestrogen-Induced Brain Aromatase Activity But Do Not Prevent Xenoestrogen-Induced Feminization In Japanese Medaka (Oryzias Latipes), Adam J. Kuhl, Marius Brouwer

Faculty Publications

In fish, exposure to estrogen or estrogen-mimicking chemicals (xenoestrogeus)during a critical period of development can irreversibly invert sex differentiation. In medaka, a male-to-female reversal upon exposure to a xenoestrogen is accompanied by an increase in brain aromatase expression and activity. However, whether this increase is the direct cause of sex reversal is unknown. In this study we further examined the role brain aromatase plays in genesis of developmental abnormalities in response to endocrine-disrupting chemicals (EDCs). Further, the effects of a mixture of apparent antagonistic environmentally relevant EDCs on development were examined to determine if their combined actions could lessen each …

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Zonal Patterns Of Delta C-13, Delta N-15 And Po-210 In The Tropical And Subtropical North Pacific, Min Chen, Laodong Guo, Qiang Ma, Yusheng Qiu, Run Zhang, E Lv, Yipu Huang

Faculty Publications

Nitrogen fixation process may supply a significant fraction of bioavailable nitrogen to surface waters, increase the oceanic sequestration of atmospheric CO2, and alter the distribution of geochemical parameters. We report a zonal pattern of delta N-15 and delta C-13 in particulate organic matter (POM), and ratios of particulate Po-210 to dissolved Po-210 along a transect through the subtropical and tropical North Pacific. Both N-15 and Po-210 signals indicated an enhanced N-2 fixation in the northwestern subtropical North Pacific. The eastward decrease of N-2 fixation along this transect testified the role of aeolian Fe and P in controlling marine N-2 fixation. …

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Baseline Mapping Of Phragmites Australis (Common Reed) In Three Coastal Mississippi Estuarine Basins, Mark S. Peterson, Melissa L. Partyka

Faculty Publications

Over the last two decades, the northern Gulf of Mexico has undergone tremendous growth and development that has resulted in extensive and ongoing habitat modification. We had the opportunity to survey the main channels and bayous of three coastal estuarine basins for the presence and coverage of the invasive Phragmites australis (common reed). The occurrence and area of P. australis was highly variable among the lower Pascagoula River, Back Bay of Biloxi, and St. Louis Bay basins, with the largest amount of coverage (0.489 km(2)) found within the lower Pascagoula River basin and the smallest in Back Bay of Biloxi …

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A Review Of Polylekithum Arnold, 1934 And Its Familial Affinities Using Morphological And Molecular Data, With Description Of Polylekithum Catahoulensis Sp Nov., Stephen S. Curran, Vasyl V. Tkach, Robin M. Overstreet

Faculty Publications

Faculty Publications

Effects Of Long-Term Hypoxia On Enzymes Of Carbohydrate Metabolism In The Gulf Killifish, Fundulus Grandis, Mery L. Mártinez, Christie Landry, Ryan Boehm, Steve Manning, Bernard B. Rees

Faculty Publications

Dissolved Gallium In The Northwest Pacific And The South And Central Atlantic Oceans: Implications For Aeolian Fe Input And A Reconsideration Of Profiles, Alan M. Shiller, Gautam Raj Bairamadgi

Faculty Publications

Source And Transport Of Terrigenous Organic Matter In The Upper Yukon River: Evidence From Isotope (𝛿c-13, Δc-14, And 𝛿n-15) Composition Of Dissolved, Colloidal, And Particulate Phases, Laodong Guo, Robie W. Macdonald

Faculty Publications

Summer Transport Estimates Of The Kamchatka Current Derived As A Variational Inverse Of Hydrophysical And Surface Drifter Data, G.G. Panteleev, P. Stabeno, V.A. Luchin, Dmitri A. Nechaev, M. Ikeda

Faculty Publications

Vittatispora, A New Melanosporaceous Genus From Indian Soil, Preeti Chaudhary, Jinx Campbell, David L. Hawksworth, Kedarnath N. Sastry

Faculty Publications

Antiestrogens Inhibit Xenoestrogen-Induced Brain Aromatase Activity But Do Not Prevent Xenoestrogen-Induced Feminization In Japanese Medaka (Oryzias Latipes), Adam J. Kuhl, Marius Brouwer

Faculty Publications

Zonal Patterns Of Delta C-13, Delta N-15 And Po-210 In The Tropical And Subtropical North Pacific, Min Chen, Laodong Guo, Qiang Ma, Yusheng Qiu, Run Zhang, E Lv, Yipu Huang

Faculty Publications

Baseline Mapping Of Phragmites Australis (Common Reed) In Three Coastal Mississippi Estuarine Basins, Mark S. Peterson, Melissa L. Partyka

Faculty Publications