Life Sciences Commons^™

Avian Hosts For West Nile Virus In St. Tammany Parish, Louisiana, 2002, Nicholas Komar, Nicholas A. Panella, Stanley A. Langevin, Aaron C. Brault, Manuel Amador, Eric Edwards, Jennifer C. Owen

Faculty Publications

West Nile virus (WNV) infections in free-ranging birds were studied in Slidell, St. Tammany Parish, Louisiana, after a human encephalitis outbreak peaked there in July 2002. Seroprevalence in resident, free-ranging wild birds in one suburban site was 25% and 24% in August and October, respectively, indicating that most transmission had ceased by early August. Mortality rates, seroprevalence rates, host competence, and crude population estimates were used in mathematical models to predict actual infection rates, population impacts, and importance as amplifying hosts for several common passerine birds. Northern cardinal (Cardinalis cardinalis) and house sparrow (Passer domesticus) were the principal amplifying hosts, …

Applications Of Phylogenetics To Issues In Freshwater Crayfish Biology, Keith A. Crandall

Faculty Publications

Freshwater crayfish have served as model organisms for over 125 years in scientific research, from areas such as neurobiology and vision research to conservation biology and evolution. Recently, evolutionary histories in the form of phylogenies have served as a critical foundation for testing hypotheses in such diverse research areas as well. In this article, I review the amazing diversity of freshwater crayfish, especially in a phylogenetic context and explore how these evolutionary histories have informed crayfish biology and can be used powerfully in the future to guide research in a diversity of areas. Throughout the article, I draw on examples …

Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell

Faculty Publications

Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. Methods: In this study, ovariectomized (OVX) female Long-Evans rats were fed either an isoflavone-rich diet (Phyto-600) or an isoflavone-free diet (Phyto-free). We examined the effects of soy isoflavones on metabolism by measuring body weights, food/water intake, adipose tissue weights as well as serum leptin levels. Also, circulating isoflavone levels were quantified. During chemically induced estrous, nociceptive thresholds were recorded. Then, the animals were subjected to a stressor and stress hormone levels were …

A Numerical Study Of The Western Cosmonaut Polynya In A Coupled Ocean-Sea Ice Model, T.G. Prasad, Julie L. Mcclean, Elizabeth C. Hunke, Albert J. Semtner, Detelina Ivanova

Faculty Publications

[1] Employing results from a 0.4 degrees, 40-level fully global, coupled ocean - sea ice model, we investigated the role of physical processes emanating from atmosphere, ocean, and ice in the initiation, maintenance, and termination of a sensible heat polynya with a focus on the western Cosmonaut polynya that occurred during May - July 1999. The Cosmonaut polynya first appeared in early May 1999 in the form of an ice-free embayment, transformed into an enclosed polynya on 5 - 9 July, and disappeared by late July, when the ice from the surrounding regions began to encircle the embayment. Except for …

Remotely Sensed Data To Map Forest Age Class By Cover Type In East Texas, Daniel Unger, I-Kuai Hung, Jeffrey M. Williams, James Kroll, Dean W. Coble, Jason Grogan

Faculty Publications

• Remote sensing in conjunction with ground truthing, can accurately quantify forest composition and age distributions in East Texas.
• Method uses standardized and readily available data available to the general public.
• Method was shown to be effective in terms of time and cost.

Structure Of Human Thymidylate Synthase Under Low-Salt Conditions, Leslie L. Lovelace, Wladek Minor, Lukasz Lebioda

Faculty Publications

Human thymidylate synthase, a target in cancer chemotherapy, was crystallized from PEG 3350 with 30 mM ammonium sulfate (AS) in the crystallization medium. The crystals are isomorphous with the high-salt crystals (~2.0 M AS) and the structure has been solved and refined (R = 22.6%, Rfree = 24.3%) at 1.8 Å resolution. The high- and low-AS-concentration structures are quite similar, with loop 181-197 is in the inactive conformation. Also, residues 95-106 and 129-135 (eukaryotic inserts region) show high mobility as assessed by poor electron density and high values of crystallographic temperature factors (residues 1-25 and 108-129 are disordered in both …

Distribution Of Hydrogen Peroxide In The Northwest Pacific Ocean, Jinchun Yuan, Alan M. Shiller

Faculty Publications

[1] Hydrogen peroxide (H2O2) is a reactive oxygen intermediate involved in the cycling of metals and dissolved organic matter. Because little is known of its distribution in the North Pacific Ocean, we determined H2O2 in surface waters continuously and obtained vertical profiles at nine stations during a cruise from Japan to Hawaii. Surface water H2O2 varied from less than 10 to more than 250 nmol dm(-3). A diel cycle in surface water H2O2 (similar to 25 nmol dm(-3)) was observed only on one day during the monthlong cruise. This is contrary to expectations based on the usual assumption of photo-production …

Soy Isoflavone Glycitein Protects Against Beta Amyloid-Induced Toxicity And Oxidative Stress In Transgenic Caenorhabditis Elegans, Astrid Gutierrez-Zepeda, Ross Santell, Zhixin Wu, Marishka Brown, Yanjue Wu, Ikhlas Khan, Christopher D. Link, Baolu Zhao, Yuan Luo

Faculty Publications

Background

Epidemiological studies have associated estrogen replacement therapy with a lower risk of developing Alzheimer's disease, but a higher risk of developing breast cancer and certain cardiovascular disorders. The neuroprotective effect of estrogen prompted us to determine potential therapeutic impact of soy-derived estrogenic compounds. Transgenic C. elegans, that express human beta amyloid (Aβ), were fed with soy derived isoflavones genistein, daidzein and glycitein (100 μg/ml) and then examined for Aβ-induced paralysis and the levels of reactive oxygen species.

Results

Among the three compounds tested, only glycitein alleviated Aβ expression-induced paralysis in the transgenic C. elegans. This activity of …

Toward Sequencing The Sorghum Genome: A U.S. National Science Foundation-Sponsored Workshop Report, Stephen Kresovich, Brad Barbazuk, Joseph A. Bedell, Andrew Borrell, C. Robin Buell, John Burke, Sandra Clifton, Marie-Michéle Cordonnier-Ptratt, Stan Cox, Jeff Dahlberg, John Erpelding, Theresa M. Fulton, Bob Fulton, Lucinda Fulton, Alan R. Gingle, C. Tom Hash, Yinghua Huang, David Jordan, Patricia E. Klein, Robert R. Klein, Jurandir Magalhaes, Richard Mccombie, Paul Moore, John E. Mullet, Peggy Ozias-Akins, Andrew H. Paterson, Kay Porter, Lee Pratt, Bruce Roe, William Rooney, Patrick S. Schnable, David M. Stelly, Mitchell Tuinstra, Doreen Ware, Ujwala Warek

Faculty Publications

Members of the worldwide sorghum (Sorghum spp.) community, including private sector and international scientists as well as community representatives from closely related crops such as sugarcane (Saccharum spp.) and maize (Zea mays), met in St. Louis, Missouri, on November 9, 2004, to lay the groundwork for future advances in sorghum genomics and, in particular, to coordinate plans for sequencing of the sorghum genome. Key developments that made this workshop timely included advances in knowledge of the sorghum genome that provide for the development of a genetically anchored physical map to guide sequence assembly and annotation, the …

Extraocular Muscle Activity, Rapid Eye Movements And The Development Of Active And Quiet Sleep, Adele M. H. Seelke, Andrew J. Gall, Karl Æ. Karlsson, Mark S. Blumberg

Faculty Publications

Rapid eye movements (REMs), traditionally measured using the electrooculogram (EOG), help to characterize active sleep in adults. In early infancy, however, they are not clearly expressed. Here we measured extraocular muscle activity in infant rats at 3 days of age (P3), P8 and P14-15 in order to assess the ontogeny of REMs and their relationship with other forms of sleep-related phasic activity. We found that the causal relationship between extraocular muscle twitches and REMs strengthened during the first two postnatal weeks, reflecting increased control of the extraocular muscles over eye movements. As early as P3, however, phasic bursts of extraocular …

Bioluminescence Intensity Modeling And Sampling Strategy Optimization, I. Shulman, D.J. Mcgillicuddy Jr., M.A. Moline, S.H.D. Haddock, J.C. Kindle, D. Nechaev

Faculty Publications

The focus of this paper is on the development of methodology for short-term (1-3 days) oceanic bioluminescence (BL) predictions and the optimization of spatial and temporal bioluminescence sampling strategies. The approach is based on predictions of bioluminescence with an advection-diffusion-reaction (tracer) model with velocities and diffusivities from a circulation model. In previous research, it was shown that short-term changes in some of the salient features in coastal bioluminescence can be explained and predicted by using this approach. At the same time, it was demonstrated that optimization of bioluminescence sampling prior to the forecast is critical for successful short-term BL predictions …

A Modified Poisson–Boltzmann Analysis Of The Capacitance Behavior Of The Electric Double Layer At Low Temperatures, Douglas Henderson, L. B. Bhuiyan, C. W. Outhwaite

Faculty Publications

The modified Poisson–Boltzmann theory is used to analyze the anomalous behavior of the electric double layer capacitance for small surface charge at low temperatures and densities. Good agreement is found with simulation and recent density-functional theory results. Negative adsorption is also found in line with theory and simulation. An unsatisfactory feature is the relatively poor structure in this region due to the inherent approximations in the theory. This feature is unimportant in relation to the capacitance results but has implications when calculating adsorption properties.

Effects Of Long-Term Storage On Quality Of Retail-Packaged Pinto Beans, C. M. Larson, A. R. Sloan, Lynn V. Ogden, Oscar A. Pike

Faculty Publications

There is interest in storing low-moisture foods for long periods of time for uses such as personal preparedness, disaster relief efforts and space travel. Pinto beans in restaurant-sized No. 10 cans are available in the retail market, but work is needed to determine the effects of long-term storage on quality. The objective of this research was to investigate the quality of retail-packaged pinto beans held at ambient temperatures up to 32 years. Fifteen samples of pinto beans packaged in No. 10 cans, which were treated to remove oxygen, were obtained from donors. Samples ranged from <1 to 32 years in age. Prior to cooking, pinto bean samples were soaked in water containing varying levels of baking soda to standardize textural attributes.

Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak

Faculty Publications

A theoretically based closed-form analytical equation for the radial distribution function, g(r), of a fluid of hard spheres is presented and used to obtain an accurate analytic representation. The method makes use of an analytic expression for the short- and long-range behaviors of g(r), both obtained from the Percus-Yevick equation, in combination with the thermodynamic consistency constraint. Physical arguments then leave only three parameters in the equation of g(r) that are to be solved numerically, whereas all remaining ones are taken from the analytical solution of the Percus-Yevick equation.

Photochemical Transformations Of Riverine Dissolved Organic Matter: Effects On Estuarine Bacterial Metabolism And Nutrient Demand, Erik M. Smith, Ronald Benner

Faculty Publications

By experimentally simulating the exposure of terrigenous dissolved organic matter (DOM) to sunlight during the mixing of river water and seawater in an estuary (St. Helena Sound, South Carolina), this study examined how photochemical alterations may affect both the magnitude and fate of DOM utilization by estuarine bacteria. In a series of experiments performed with water samples collected from 3 blackwater rivers draining into an estuary of the South Atlantic Bight (USA), exposure to light resulted in significant decreases in dissolved organic carbon (DOC) concentration and DOM absorption at 350 nm relative to dark controls. When these water samples were …

Optimal Ankle Axis Position For Articulated Footwear, Dustin A. Bruening, James G. Richards

Faculty Publications

An articulated boot design is commonly used in skiing and skating sports because it allows sagittal plane ankle mobility while still providing critical frontal plane stability. Although articulated boots have been in use for several decades, current manufacturers of these boots differ in their articulation placement. In this study we determined an optimal position of the ankle articulation axis. We also calculated the amount of anterior skin movement that a boot tongue must account for during a full range of ankle motion. Three‐dimensional kinematic data were collected and analyzed from 40 participants moving their right foot through a full range …

Effects Of Long-Term Storage On Quality Of Wheat Packaged In No. 10 Cans, R. Green, Devin J. Rose, Lynn V. Ogden, Oscar A. Pike

Faculty Publications

There is interest in the long-term storage of low-moisture foods for applications such as space flight, disaster relief, and personal preparedness. Wheat packaged in restaurant-size No. 10 cans has been available in the retail market for decades. However, the quality of such wheat held in long-term storage is not well characterized. The purpose of this research was to examine the effects of long-term storage on the quality of wheat packaged in No. 10 cans and held at ambient temperatures up to 32 years. Twenty samples of hard red wheat (including 4 duplicates) packaged in No. 10 cans were obtained from …

Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir

Faculty Publications

Prochlorococcus and Synechococcus are major prokaryotic primary producers in the oligotrophic oceans that may be affected by the climate-related increases in nitrogen fixation and subsequent phosphorus (P) limitation in some parts of the oceans. Evidence that Prochlorococcus populations in the North Pacific subtropical gyre (NPSG) have increased over the past decades, possibly due to having a competitive advantage under conditions of P limitation, suggests aspects of their Pphysiology that are important for dictating their in situ success. Here, we compared the physiology of P acquisition and response to P stress (indicated by alkaline phosphatase activity, APA) among isolates of Prochlorococcus …

Effects Of Density On Timing Of Emergence And Its Consequences For Survival And Growth In Two Communities Of Annual Plants, Roy Turkington, Deborah E. Goldberg, Linda Olsvig-Whittaker, Andrew R. Dyer

Faculty Publications

We tested whether increasing seed density results in a change in the timing of emergence in two communities of sand dune annual plants in Israel. Specifically we tested (i) if emergence is accelerated or delayed due to high seed density. We also tested two predictions about the consequences of changes in the timing of emergence; (ii) seedlings emerging earlier will have higher survival and growth; (iii) the advantage of earlier emergence increases as seed density increases. We examined these predictions for both monocots and dicots growing under different irrigation regimes and using species from a desert and a semi-arid community …

The Neural Substrates Of Infant Sleep In Rats, Karl Æ. Karlsson, Andrew J. Gall, Ethan J. Mohns, Adele M. H. Seelke, Mark S. Blumberg

Faculty Publications

Sleep is a poorly understood behavior that predominates during infancy but is studied almost exclusively in adults. One perceived impediment to investigations of sleep early in ontogeny is the absence of state-dependent neocortical activity. Nonetheless, in infant rats, sleep is reliably characterized by the presence of tonic (i.e., muscle atonia) and phasic (i.e., myoclonic twitching) components; the neural circuitry underlying these components, however, is unknown. Recently, we described a medullary inhibitory area (MIA) in week-old rats that is necessary but not sufficient for the normal expression of atonia. Here we report that the infant MIA receives projections from areas containing …

Hibernation Is Recorded In Lower Incisors Of Recent And Fossil Ground Ssquirrels (Spermophilus), Tom Goodwin, Gail R. Michener, Daniel Gonzalez, Caroline E. Rinaldi

Faculty Publications

Incremental dentin and associated enamel, features visible on the surface of lower incisors, were characterized for 3 species of ground squirrels (Spermophilus): Pleistocene and Recent S. elegans, Recent S. richardsonii, and Recent S. parryii. A hibernation mark was evident in incisor dentin and enamel, most characteristically as a sleeve of enamel terminating basally adjacent to medially depressed dentin with indistinct and often very fine increments. This mark was absent in juveniles but present in older animals of both sexes for at least 6 weeks after hibernation, eventually being lost through growth and wear of the incisor. Temporal association with hibernation …

Neotypification Of Lulworthia Fucicola, Jinx Campbell

Faculty Publications

There are no herbarium specimens or culture material for the type of Lulworthia fucicola G.K. Sutherl. With the absence of original material, and to preserve current usage of the name, a neotype is designated hereby. The neotype chosen for L. fucicola is a specimen from Chile.

Differential Rhizosphere Establishment And Cyanide Production By Alginate-Formulated Weed-Deleterious Rhizobacteria, Horace G. Gurley, Robert E. Zdor

Faculty Publications

The effects of Pseudomonas putida ATH2-1RI/9 and Acidovorax delafieldii ATH2-2RS/1 on rhizosphere colonization, cyanide production, and growth of velvetleaf and corn was examined. When formulated in alginate beads and inoculated onto velvetleaf and corn plants (109 CFU/plant), only P. putida ATH2-1RI/9 consistently reduced velvetleaf growth. Neither isolate inhibited corn growth. Interestingly the levels of P. putida ATH2-1RI/9 in the velvetleaf rhizosphere were 1000-fold higher (7 × 107 CFU/g root) than the A. delafieldii ATH2-2RS/1 populations. Cyanide (53-68 mM/g root) was recovered from the P. putida ATH2-1RI/9-inoculated velvetleaf plants. In contrast both A. delafieldii ATH2-2RS/1 and P. putida ATH2-1RI/9 colonized the …

Reporting Quality Of Randomized Trials In The Diet And Exercise Literature For Weight Loss, Cheryl A. Gibson, Erik P. Kirk, James D. Lecheminant, Bruce W. Bailey Jr, Guoyuan Huang, Joseph E. Donnelly

Faculty Publications

Background

To adequately assess individual studies and synthesize quantitative research on weight loss studies, transparent reporting of data is required. The authors examined the reporting quality of randomized trials in the weight loss literature, focusing exclusively on subject characteristics as they relate to enrollment, allocation, and follow-up.

Methods

An extensive literature review, which included a computerized search of the MEDLINE database, manual searches of bibliographic references, and cross-referencing of 92 review articles was conducted. A checklist, based on CONSORT recommendations, was used to collect information on whether or not authors reported age, gender, co-morbid disease, medication use, race/ethnicity, and postmenopausal …

A Study Of Wave Effects On Wind Stress Over The Ocean In A Fetch-Limited Case, Jiayi Pan, David W. Wang, Paul A. Hwang

Faculty Publications

A field experiment was conducted for collecting three-dimensional wind, wave, and air-sea environmental data off the coast of Louisiana in the Gulf of Mexico in the mixed sea state of a wind sea limited by fetch and with swell propagating against the wind direction. Two methods, the inertial dissipation (ID) and eddy correlation (EC), are used to calculate wind stress. The results show that under the fetch-limited condition, the EC wind stress is greater than the ID stress. This difference is found to be correlated with the counter-wind swell. The swell-related drag coefficient is computed from the wind stress difference …

Consequences Of The Historical Demography On The Global Population Structure Of Two Highly Migratory Cosmopolitan Marine Fishes: The Yellowfin Tuna (Thunnus Albacares) And The Skipjack Tuna (Katsuwonus Pelamis), Bert Ely, Jordi Viñas, Jaime R. Alvarado Bremer, Donna Black, Luciano Lucas, Kelly Covello, Alexis V. Labrie, Eric Thelen

Faculty Publications

Background

Yellowfin and skipjack tuna are globally distributed in the world's tropical and sub-tropical oceans. Since little, if any, migration of these fishes occurs between the Atlantic and Indo-Pacific Oceans, one might expect to see genetic differences between sub-populations in these ocean basins. However, yellowfin and skipjack tuna have extremely large population sizes. Thus, the rate of genetic drift should be slower than that observed for other tunas.

Results

Low levels of genetic differentiation were observed between Atlantic and Pacific samples of yellowfin tuna. In contrast, no genetic differentiation was observed between Atlantic and Pacific samples of skipjack tuna.

Conclusion …

Temperature Dependence Of The Double Layer Capacitance For The Restricted Primitive Model Of An Electrolyte Solution From A Density Functional Approach, Douglas Henderson, J. Reszko-Zygmunt, Stefan Sokolowski, Dezso Boda

Faculty Publications

We apply a different version of the density functional theory, given by Pizio, Patrykiejew, and Sokolowski [J. Chem. Phys. 121, 11957 (2004)], for a nonuniform restricted primitive model of an electrolyte solution to evaluate the temperature dependence of the capacitance of an electric double layer. We show that this theory is capable of reproducing the computer simulation data at a quantitative level. In particular, the reversal of the temperature dependence of the capacitance at low temperatures is predicted. This phenomenon has been difficult to predict from theory. Further, this theory also leads to an accurate description of the double layer …

Predicting Numbers Of Hauled-Out Harbour Seals: A Mathematical Model, James L. Hayward, Shandelle M. Henson, Clara J. Logan, Catherine R. Parris, Matthew W. Meyer, Brian Dennis

Faculty Publications

1. It was once assumed that commercially important fish make up significant portions of seal diets. As a consequence, prior to the 1970s many seal populations were dramatically reduced by rampant slaughtering. Today, seals and other marine mammals are valued components of marine ecosystems and their numbers are carefully managed. To facilitate management, government statutes mandate the systematic monitoring of seal populations. Population estimates are based on counts of hauled-out seals obtained by aerial survey and radio and satellite telemetry; hence, considerable effort has been devoted to finding optimal times for such counts. We have developed a predictive mathematical model …

Ponazuril Inhibits The Development Of Eimeria Vermiformis In Experimentally Infected Outbred Swiss Mice, S. A. Billeter, J. A. Spencer, Bill Chobotar, B. L. Blagburn

Faculty Publications

We evaluated a 15% paste formulation of ponazuril in outbred Swiss mice that were experimentally infected with Eimeria vermiformis. Thirty, 8-week-old female mice (approximately 20 g) were placed in one group of 10 mice and one group of 20 mice. Mice in both groups were gavaged with approximately 5,000 sporulated oocysts of E. vermiformis on day 0. Mice in group 2 (n=10) were treated orally on days 3 and 4 with ponazuril (suspended in 30% propylene glycol) at the rate of 20 mg/kg. Mice in group 1 (n=20) were gavaged with a similar volume of 30% propylene glycol. Rates of …

A Regional Food-Frequency Questionnaire For The Us Mississippi Delta, Katherine L. Tucker, Janice Maras, Catherine Champagne, Carol L. Connell, Susan Goolsby, Judith Weber, Sahar Zaghloul, Teresa Carithers, Margaret L. Bogle

Faculty Publications

Objective: To describe food sources of nutrient intake for white and African American adults in the Lower Mississippi Delta (LMD), and their use in the development of a regional food-frequency questionnaire (FFQ) based on an earlier version of the National Cancer Institute's Health Habits and History Questionnaire. Design: We ranked food sources of energy, macronutrients, vitamins and minerals, and examined portion size distributions for 842 white and 857 African American residents aged 19 years and older, using 24-hour dietary intake recall data from a telephone survey of 36 LMD counties. These values were used to develop a regional FFQ, which …