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Nutrient Cycling In The Water Column Of A Subtropical Seagrass Meadow, Susan Ziegler, Ronald Benner Nov 1999

Nutrient Cycling In The Water Column Of A Subtropical Seagrass Meadow, Susan Ziegler, Ronald Benner

Faculty Publications

The cycling of nutrients was studied over a 16 mo period to determine how processes occurring between the water column and benthos influenced nutrient dynamics in a Thalassia testudinum dominated seagrass meadow. Nutrient concentrations were low and ranged from below detection to 0.59 µM ammonium (NH4+), 0.04 to 0.29 µM nitrate plus nitrite (NO3- + NO2-), and below detection to 0.22 µM soluble reactive phosphate (SRP). Water column and benthic fluxes of NO3- + NO2- and SRP were usually below detection. The benthic fluxes of NH4+ …

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Tracking Of Physical Activity, Physical Inactivity, And Health-Related Physical Fitness In Rural Youth, Russell R. Pate, Stewart G. Trost, Marsha Dowda, Alise E. Ott, Dianne S. Ward, Ruth P. Saunders, Gwen A. Felton Nov 1999

Tracking Of Physical Activity, Physical Inactivity, And Health-Related Physical Fitness In Rural Youth, Russell R. Pate, Stewart G. Trost, Marsha Dowda, Alise E. Ott, Dianne S. Ward, Ruth P. Saunders, Gwen A. Felton

Faculty Publications

This study examined the tracking of selected measures of physical activity, inactivity, and fitness in a cohort of rural youth. Students (N=181, 54.7% female, 63.5% African American) completed test batteries during their fifth- (age=10.7±0.7 years), sixth-, and seventh-grade years. The Previous Day Physical Activity Recall (PDPAR) was used to assess 30-min blocks of vigorous physical activity (VPA), moderate-to-vigorous physical activity (MVPA), TV watching and other sedentary activities, and estimated energy expenditure (EE). Fitness measures included the PWC 170 cycle ergometer test, strength tests, triceps skinfold thickness, and BMI. Intraclass correlation coefficients (ICCs) for VPA, MVPA, and after-school EE …

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Biogeochemical Transformations And Potential Polyaromatic Hydrocarbon Degradation In Macrofaunal Burrow Sediments, W. K. Chung, Gary M. King Oct 1999

Biogeochemical Transformations And Potential Polyaromatic Hydrocarbon Degradation In Macrofaunal Burrow Sediments, W. K. Chung, Gary M. King

Faculty Publications

A variety of polyaromatic hydrocarbons (PAH) including naphthalene, phenanthrene, acenaphthene, and dibenzothiophene were degraded with little or no lag in oxic slurries of marine sediments from burrow walls constructed by benthic macrofauna. PAH degradation potentials of burrow sediments from the polychaetes Nereis virens and Clymenella torquata, the mollusc Mya arenaria and the enteropneust Saccoglossus bromophenolosus were generally greater than potentials for non-burrow sediments; relative rates of degradation varied among the burrow wall sediments depending on the PAH assayed. Comparisons of the effects of available electron acceptors (oxygen, nitrate, ferric iron, sulfate) indicated that significant degradation of benzene, hexadecane and PAH …

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Synthesis And Unusual Properties Of The First 2,3,7,8,12,13,17,18-Octabromo-5,10,15,20-Tetraalkylporphyrin, Nora Y. Nelson, Craig J. Medforth, Daniel J. Nurco, Song Ling Jia, John A. Shelnutt, Kevin M. Smith Oct 1999

Synthesis And Unusual Properties Of The First 2,3,7,8,12,13,17,18-Octabromo-5,10,15,20-Tetraalkylporphyrin, Nora Y. Nelson, Craig J. Medforth, Daniel J. Nurco, Song Ling Jia, John A. Shelnutt, Kevin M. Smith

Faculty Publications

The new perhalogenated porphyrin 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(trifluoromethyl)porphinato -nickel(II) exhibits several striking features, including an extremely ruffled macrocycle with a very short Ni-N distance, an unusually red-shifted optical spectrum, and, surprisingly, hindered rotation of the meso-trifluoromethyl substituents (ΔG2+78 = 47 kJ mol-1).

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Children's Interests In A Family Context - A Cautionary Note, James G. Dwyer Oct 1999

Children's Interests In A Family Context - A Cautionary Note, James G. Dwyer

Faculty Publications

No abstract provided.

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Collisional Dynamics Of Bi2 A(0U+). I. Quantum-Resolved Vibrational Energy Transfer For V′=0–4, Robert E. Franklin, Glen P. Perram Oct 1999

Collisional Dynamics Of Bi2 A(0U+). I. Quantum-Resolved Vibrational Energy Transfer For V′=0–4, Robert E. Franklin, Glen P. Perram

Faculty Publications

Vibrational-to-translational energy transfer between the lowest vibrational levels (v′=0–4) of the A(0+u) state of Bi2 has been investigated using spectrally resolved, laser-induced fluorescence techniques. The small vibrational spacing (ω′e≃132 cm−1) leads to highly nonadiabatic conditions, particularly for the Bi2(A)–He collision pair. However, the Δv=−1 transition probabilities for collisions with the rare gases range from 0.75% to 1.75% per collision, considerably lower than would be anticipated from standard vibrational energy transfer theory. Multiquantum (Δv′=±2) transfer rates are low, consistent with the low anharmonicity of the A(0+u) state. The rates for …

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Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls Sep 1999

Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls

Faculty Publications

No abstract provided.

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Mathematical Modelling Of Extracellular Matrix Dynamics Using Discrete Cells: Fiber Orientation And Tissue Regeneration, J. C. Dallon, J. A. Sherratt, P. K. Maini Aug 1999

Mathematical Modelling Of Extracellular Matrix Dynamics Using Discrete Cells: Fiber Orientation And Tissue Regeneration, J. C. Dallon, J. A. Sherratt, P. K. Maini

Faculty Publications

Matrix orientation plays a crucial role in determining the severity of scar tissue after dermal wounding. We present a model framework which allows us to examine the interaction of many of the factors involved in orientation and alignment. Within this framework, cells are considered as discrete objects, while the matrix is modeled as a continuum. Using numerical simulations, we investigate the effect on alignment of changing cell properties and of varying cell interactions with collagen and fibrin.

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Wetlands: A Potentially Significant Source Of Atmospheric Methyl Bromide And Methyl Chloride, Ruth K. Varner, Patrick M. Crill, Robert W. Talbot Aug 1999

Wetlands: A Potentially Significant Source Of Atmospheric Methyl Bromide And Methyl Chloride, Ruth K. Varner, Patrick M. Crill, Robert W. Talbot

Faculty Publications

Tropospheric methyl bromide (CH3Br) and methyl chloride (CH3Cl) are significant sources of ozone (O3) destroying halogens to the stratosphere. Their O3 depletion potential (ODP) can be determined from atmospheric lifetimes and therefore their atmospheric budgets, both of which are out of balance with known sink terms larger than identified sources. We have discovered a new source of CH3Br and CH3Cl emissions to the atmosphere at two wetland sites in the Northeastern United States. We have reason to believe that these compounds are biologically produced in situ. Our measurements indicate that the global annual flux of CH3Br and CH3Cl from wetlands …

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Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich Aug 1999

Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich

Faculty Publications

No abstract provided.

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A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

A relaxation network model that includes higher order weight connections is introduced. To demonstrate its utility, the model is applied to the speech recognition domain. Traditional speech recognition systems typically consider only that context preceding the word to be recognized. However, intuition suggests that considering both preceding context as well as following context should improve recognition accuracy. The work described here tests this hypothesis by applying the higher order relaxation network to consider both precedes and follows context in speech recognition. The results demonstrate both the general utility of the higher order relaxation network as well as its improvement over …

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Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng Jul 1999

Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

This work focuses on improving the Hopfield network for solving optimization problems. Although much work has been done in this area, the performance of the Hopfield network is still not satisfactory in terms of valid convergence and quality of solutions. We address this issue in this work by combing a new activation function (EBA) and a new relaxation procedure (CR) in order to improve the performance of the Hopfield network. Each of EBA and CR has been individually demonstrated capable of substantially improving the performance. The combined approach has been evaluated through 20,000 simulations based on 200 randomly generated city …

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The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

Constraint satisfaction networks contain nodes that receive weighted evidence from external sources and/or other nodes. A relaxation process allows the activation of nodes to affect neighboring nodes, which in turn can affect their neighbors, allowing information to travel through a network. When doing discrete updates (as in a software implementation of a relaxation network), a goal net or goal activation can be computed in response to the net input into a node, and a relaxation rate can then be used to determine how fast the node moves from its current value to its goal value. An open question was whether …

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Seeking Causal Explanations In Social Epidemiology, Jay S. Kaufman, Richard S. Cooper Jul 1999

Seeking Causal Explanations In Social Epidemiology, Jay S. Kaufman, Richard S. Cooper

Faculty Publications

Social factors are associated with a wide variety of health outcomes. Social epidemiology has successfully used the traditional methods of surveillance and description to establish consistent relations between social factors and health status. Epidemiology as an etiologic science, however, has been largely ineffective in moving toward causal explanations for these observed patterns. Using the counterfactual approach to causal inference, the authors describe several fundamental problems that often arise when researchers seek to infer explanatory mechanisms from data on social factors. Contrasts that form standard causal effect estimates require implicit unobserved (counterfactual) quantities, because observational data provide only one exposure state …

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The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth Jul 1999

The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth

Faculty Publications

Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will …

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Dietary Assimilation Of Cadmium Associated With Bacterial Exopolymer Sediment Coatings By The Estuarine Amphipod Leptocheirus Plumulosus: Effects Of Cd Concentration And Salinity, Christian E. Schlekat, Alan W. Decho, G. Thomas Chandler Jul 1999

Dietary Assimilation Of Cadmium Associated With Bacterial Exopolymer Sediment Coatings By The Estuarine Amphipod Leptocheirus Plumulosus: Effects Of Cd Concentration And Salinity, Christian E. Schlekat, Alan W. Decho, G. Thomas Chandler

Faculty Publications

Bacterial extracellular substances (also known as exopolysaccharides, or EPS) may serve as vectors for trophic transfer of metals in benthic systems because these ubiquitous sediment coatings can sorb high concentrations of toxic metals, and because many benthic invertebrates assimilate EPS sediment coatings upon ingestion. We conducted 3 sets of experiments to determine the assimilative bioavailability of EPS-associated Cd to the benthic amphipod Leptocheirus plumulosus as a function of Cd concentration and salinity. Bioavailability was measured as L. plumulosus Cd assimilation efficiency (AE) from EPS-coated silica (EPS●Si) and from uncoated silica (NC●Si) using modified pulse-chase methods with the gamma-emitting radioisotope 109 …

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Blue Crab Larval Dispersion And Retention In The Mississippi Bight, Donald R. Johnson, Harriet M. Perry Jul 1999

Blue Crab Larval Dispersion And Retention In The Mississippi Bight, Donald R. Johnson, Harriet M. Perry

Faculty Publications

A conceptual hypothesis relating physical forcing to dispersion and retention was developed for blue crab larvae within the Mississippi Eight. The spawning period for blue crabs in the northern Gulf of Mexico is protracted. Hatching of eggs occurs near the barrier islands and mouths of coastal bays from March through October. Larvae are released on ebbing tides and spend the next 30 to 50 d offshore where they develop through seven zoeal stages before undergoing metamorphosis to megalopae. Duration of the megalopal stage is variable but generally persists from 6 to 20 d. Blue crabs recruit to Gulf estuaries as …

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Age And Growth Of Cobia, Rachycentron Canadum, From The Northeastern Gulf Of Mexico, James S. Franks, James R. Warren, Michael V. Buchanan Jul 1999

Age And Growth Of Cobia, Rachycentron Canadum, From The Northeastern Gulf Of Mexico, James S. Franks, James R. Warren, Michael V. Buchanan

Faculty Publications

We examined 1005 cobia, Rachycentron canadum, from recreational catches in the northeastern Gulf of Mexico from 1987 to 1995. Specimens ranged from 325 to 1651 mm fork length (FL); females had a mean FL of 1050 mm (n=730) and were significantly larger than males that had a mean FL of 952 mm (n=275). The over all male to female ratio was 1:2.7. Ages of 565 cobia were estimated from thin-sectioned otoliths (sagittae). Marginal-increment analysis of sagittal otoliths showed a single annual minimum during June. Male cobia (n=170; 525-1330 mm FL) ranged from age 0 to 9, and females (n=395; 493-1651 …

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Film Formation By Marine Bacteria At A Model Fluid Interface, Vera Zutic, Nadica Ivosevic, Vesna Svetlicic, Richard A. Long, Farooq Azam Jun 1999

Film Formation By Marine Bacteria At A Model Fluid Interface, Vera Zutic, Nadica Ivosevic, Vesna Svetlicic, Richard A. Long, Farooq Azam

Faculty Publications

We have characterized the nonspecific interactions in the initial attachment and film formation by marine bacteria at a dynamic fluid interface: seawater/dropping mercury electrode. Experimental evidence is presented that bacteria readily establish molecular contact with the metal substrate without mediation of a conditioning film. Prevalence of hydrophobic over electrostatic interactions and the possible importance of Ca2+ bridging could be inferred. The attachment of individual bacterial cells is faster than their transport from the aqueous medium, as is the case in the transport-controlled adsorption of biopolymers. The cell aggregates yield distinct electrical attachment signals, allowing a comparison between cell-cell and …

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Black-White Differences In Disability And Morbidity In The Last Years Of Life, Youlian Liao, Daniel L. Mcgee, Guichan Cao, Richard S. Cooper Jun 1999

Black-White Differences In Disability And Morbidity In The Last Years Of Life, Youlian Liao, Daniel L. Mcgee, Guichan Cao, Richard S. Cooper

Faculty Publications

To assess black-white differences in disability and morbidity in the last years of life, the authors analyzed data from the National Health Interview Survey from 1986 to 1994, with mortality follow-up through December 1995. A baseline household interview was conducted for 10,187 decedents aged 50 years and over within 2 years before death. Data collected included long- term limitation of activity, number of chronic conditions, number of bed days, doctor visits, and days of short hospital stay during the year preceding the interview. For both blacks and whites, educational attainment was inversely associated with disability/morbidity indices. Black decedents had greater …

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Local Data Assimilation In The Estimation Of Barotropic And Baroclinic Open Boundary Conditions, Igor Shulman, James K. Lewis, John G. Mayer Jun 1999

Local Data Assimilation In The Estimation Of Barotropic And Baroclinic Open Boundary Conditions, Igor Shulman, James K. Lewis, John G. Mayer

Faculty Publications

The problem of data assimilation in the specification of open boundary conditions for limited area models is addressed in this paper. Optimization approaches are detailed, which are based on combining available data on an open boundary with the physics of the hydrodynamical model. In our case the physics is in terms of the flux of energy through the open boundary. These optimized boundary conditions, for both barotropic and baroclinic situations, interpreted physically as special Linearizations of the Bernoulli equation for each normal mode. Because of the complexity of decomposing variables into normal modes for open boundaries with varying bathymetry, we …

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Phytochelatin Synthase Genes From Arabidopsis And The Yeast Schizosaccharomyces Pombe, Suk Bong Ha, Aaron P. Smith, Ross Howden, Wendy M. Dietrich, Sarah Bugg, Matthew J. O'Connell, Peter B. Goldsbrough, Christopher S. Cobbett Jun 1999

Phytochelatin Synthase Genes From Arabidopsis And The Yeast Schizosaccharomyces Pombe, Suk Bong Ha, Aaron P. Smith, Ross Howden, Wendy M. Dietrich, Sarah Bugg, Matthew J. O'Connell, Peter B. Goldsbrough, Christopher S. Cobbett

Faculty Publications

Phytochelatins (PCs), a family of heavy metal-inducible peptides important in the detoxification of heavy metals, have been identified in plants and some microorganisms, including Schizosaccharomyces pombe, but not in animals. PCs are synthesized enzymatically from glutathione (GSH) by PC synthase in the presence of heavy metal ions. In Arabidopsis, the CAD1 gene, identified by using Cd-sensitive, PC-deficient cad1 mutants, has been proposed to encode PC synthase. Using a positional cloning strategy, we have isolated the CAD1 gene. Database searches identified a homologous gene in S. pombe, and a mutant with a targeted deletion of this gene was also Cd sensitive …

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The Long Isoform Uncoupling Protein-3 (Ucp3l) In Human Energy Homeostasis, W. K. Chung, A. Luke, R. S. Cooper, C. Rotini, A. Vidal-Puig, M. Rosenbaum, D. Gordon, S. M. Leal, S. Caprio, R. Goldsmith, A. L. Andreu, C. Bruno, S. Dimauro, M. Heo, W. L. Lowe, B. B. Lowell, D. B. Allison, R. L. Leibel Jun 1999

The Long Isoform Uncoupling Protein-3 (Ucp3l) In Human Energy Homeostasis, W. K. Chung, A. Luke, R. S. Cooper, C. Rotini, A. Vidal-Puig, M. Rosenbaum, D. Gordon, S. M. Leal, S. Caprio, R. Goldsmith, A. L. Andreu, C. Bruno, S. Dimauro, M. Heo, W. L. Lowe, B. B. Lowell, D. B. Allison, R. L. Leibel

Faculty Publications

The biological role(s) proposed for UCP3 in energy homeostasis have been based primarily upon amino acid sequence homology to UCP1. Spontaneous mutations of UCP3 have been described in humans, but not in rodents. The functional consequences—or lack thereof—of these mutations in humans will be of great importance in elucidating the biology of this protein. The results of two such studies are summarized here. © 1999 Stockton Press. All rights reserved.

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Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman Jun 1999

Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman

Faculty Publications

No abstract provided.

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The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston Jun 1999

The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston

Faculty Publications

No abstract provided.

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Dissolved Organic Carbon Cycling In A Subtropical Seagrass-Dominated Lagoon, Susan Ziegler, Ronald Benner May 1999

Dissolved Organic Carbon Cycling In A Subtropical Seagrass-Dominated Lagoon, Susan Ziegler, Ronald Benner

Faculty Publications

The cycling of dissolved organic matter (DOM) and its significance to ecosystem metabolism was studled over a 16 mo period in a Thalassia testudjnum dominated meadow. The benthos was usually net autotrophic (annual gross primary production to respiration ratio [P:R] = 1.3) while water column respiration (R) exceeded gross primary production (annual P:R = 0.3). Net fluxes of dissolved organic carbon (DOC) from the benthos primarily occurred in the light (0 to 18 mmol C m-2 d-1) and from seagrass-dominated areas, suggesting that release of DOC was mainly due to seagrass exudation. Net benthic DOC fluxes measured …

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The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan May 1999

The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan

Faculty Publications

The dipolar hard sphere fluid (DHSF) is a useful model of a polar fluid. However, the DHSF lacks a vapor–liquid transition due to the formation of chain-like structures. Such chains are not characteristic of real polar fluids. A more realistic model of a polar fluid is obtained by adding a Lennard–Jones potential to the intermolecular potential. Very similar results are obtained by adding a Yukawa potential, instead of the Lennard–Jones potential. We call this fluid the dipolar Yukawa fluid (DYF). We show that an analytical solution of the mean spherical approximation (MSA) can be obtained for the DYF. Thus, the …

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Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman May 1999

Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman

Faculty Publications

No abstract provided.

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The Mycobactericidal Efficacy Of Orthophthalaldehyde And The Comparative Resistances Of Mycobacterium Bovis, Mycobacterium Terrae, And Mycobacterium Chelonae, Richard A. Robison, Adam W. Gregory, G. Bruce Schaalje, Jonathan D. Smart May 1999

The Mycobactericidal Efficacy Of Orthophthalaldehyde And The Comparative Resistances Of Mycobacterium Bovis, Mycobacterium Terrae, And Mycobacterium Chelonae, Richard A. Robison, Adam W. Gregory, G. Bruce Schaalje, Jonathan D. Smart

Faculty Publications

Objectives: To assess the mycobactericidal efficacy of an agent relatively new to disinfection, ortho-phthalaldehyde (OPA) and to compare the resistances of three Mycobacterium species. Mycobacterium bovis (strain BCG) was compared with Mycobacterium chelonae and Mycobacterium terrae to investigate the feasibility of using either of the latter two species in tuberculocidal testing. M chelonae (a rapid grower) and M terrae (an intermediate grower) both grow faster and are less virulent than M bovis (a slow grower).

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Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström Apr 1999

Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström

Faculty Publications

To study the effect of substrate addition on short term bacterial population dynamics and species composition in seawater mesocosms were maintained with water collected off Scripps Pier (La Jolla, California USA) Protein enrichment (BSA) triggered a dynamic response from the microbial food web, whereas enrichment with starch had no effect. In the protein enriched mesocosm the number of both nucleoid-containing cells and metabolically active cells increased by 3.0 X 105 cells ml-1 from Day 1 to Day 4 In the same time period the density of a set of 31 phylogenetically different bacteria (α- and g-Proteobactena as well …

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