Digital Commons Network^™

Numerical Methods For The Stochastic Landau-Lifshitz Navier-Stokes Equations, Alejandro Garcia, J. B. Bell, S. Williams

Faculty Publications

The Landau-Lifshitz Navier-Stokes (LLNS) equations incorporate thermal fluctuations into macroscopic hydrodynamics by using stochastic fluxes. This paper examines explicit Eulerian discretizations of the full LLNS equations. Several computational fluid dynamics approaches are considered (including MacCormack’s two-step Lax-Wendroff scheme and the piecewise parabolic method) and are found to give good results for the variance of momentum fluctuations. However, neither of these schemes accurately reproduces the fluctuations in energy or density. We introduce a conservative centered scheme with a third-order Runge-Kutta temporal integrator that does accurately produce fluctuations in density, energy, and momentum. A variety of numerical tests, including the random walk …

Red-Cockaded Woodpecker Foraging Behavior, D. Craig Rudolph, Richard N. Conner, Richard R. Schaefer, Nancy E. Koerth

Faculty Publications

We studied Red-cockaded Woodpeckers (Picoides borealis) to examine the effect of status and gender on foraging behavior. Foraging behavior of breeding pairs extended beyond separation by foraging height to include zones (bole, trunk in crown, primary limb, secondary limb) of the tree used and foraging methods (scaling, probing, excavating). Helper males and juvenile females maintained partial spatial separation from breeding adults. Helper males maintained spatial separation from breeding adults by exploiting limbs within tree crowns in both longleaf (Pinus palustris) and loblolly-shortleaf (P. taeda, P. echinata) pine forests, but also increased use of boles in loblolly-shortleaf pine in concert with …

Morphological And Molecular Analyses Of Microorganisms In Caribbean Reef Adult Sponges And In Corresponding Reproductive Material, Susanne Schmitt, Markus Wehrl, Niels Lindquist, Jeremy B. Weisz, Ute Hentschel

Faculty Publications

Caribbean reef sponges were surveyed for the presence of microorganisms in the mesohyl tissue of adult sponges and the respective reproductive material (embryos, larvae). A clear correlation was found in that high microbial abundance (HMA) sponges always contained microorganisms in their reproductive stages. In contrast, low microbial abundance (LMA) sponges did not contain microorganisms in their reproductive stages. Based on these data, Ircinia felix Duchassaing and Michelotti, 1864 was chosen as a model organism for the molecular analysis of microorganisms within the adult sponge and its larvae and juveniles. Denaturing gradient gel electrophoresis (DGGE) of eubacterial 16S rDNA sequences revealed …

Vertical Transmission Of A Phylogenetically Complex Microbial Consortium In The Viviparous Sponge Ircinia Felix, Susanne Schmitt, Jeremy B. Weisz, Niels Lindquist, Ute Hentschel

Faculty Publications

Many marine demosponges contain large amounts of phylogenetically complex yet highly sponge-specific microbial consortia within the mesohyl matrix, but little is known about how these microorganisms are acquired by their hosts. Settlement experiments were performed with the viviparous Caribbean demosponge Ircinia felix to investigate the role of larvae in the vertical transmission of the sponge-associated microbial community. Inspections by electron microscopy revealed large amounts of morphologically diverse microorganisms in the center of I. felix larvae, while the outer rim appeared to be devoid of microorganisms. In juveniles, microorganisms were found between densely packed sponge cells. Denaturing gradient gel electrophoresis (DGGE) …

From Observers To Participants: Joining The Scientific Community, Catherine A. Reinke, Susan R. Singer, Carl Mcdaniel, Carolyn J. Ferguson, Julia Vandermeer, Adam Williamson

Faculty Publications

In this essay, we have integrated the voices of our mentors and students to explore 45 years of undergraduate research experiences and their role in shaping our scientific community. In considering our collective experiences, we see undergraduate involvement in research as a rich source of community development, one that has both touched our lives and influenced our teaching.

Potential Effects Of Sediment Dredging On Internal Phosphorus Loading In A Shallow, Subtropical Lake, K. R. Reddy, M. M. Fisher, Y. Wang, J. R. White, R. Thomas James

Faculty Publications

Long-term phosphorus (P) loading to lakes has resulted in accumulation of P in sediments. Internal nutrient loading from sediments of shallow lakes such as Lake Okeechobee, Florida, has become a major concern in restoration programs. The objectives of this study were to determine (1) the potential impact of dredging on dissolved reactive P (DRP) flux out of sediments and (2) the equilibrium P concentration (EPCw) of post-dredge sediments. Intact sediment cores from one location representing P-laden mud sediments of the lake were obtained. Four simulated dredging treatments were implemented: control (no dredging-current conditions); top 30 cm; 45 cm; and 55 …

Hurricane Signals In Salt Marsh Sediments: Inorganic Sources And Soil Volume, R. Eugene Turner, E M. Swenson, C S. Milan, J M. Lee

Faculty Publications

The inorganic content of 51 dated sediment cores from Mississippi River deltaic plain salt marsh wetlands peaks with the landfall of hurricanes. Variations in the inorganic sediment content demonstrate no temporal coherence with changes in either the Mississippi River suspended matter concentration or discharge, or with wetland losses on this coast. The inorganic matter brought to wetlands during hurricanes is sufficient to account for the accumulated inorganic sediment, and the volume averages 9% of the soil volume. A sediment deficit'' hypothesis, which makes a causal connection between a changing inorganic supply and the dramatically high wetland losses on this coast, …

Managing Coastal Resources In The 21st Century, M P. Weinstein, R C. Baird, D O. Conover, M Gross, M P. Weinstein, D K. Loomis, Z Naveh, S B. Peterson, D J. Reed, E Roe, R L. Swanson, J A. Swart, J M. Teal, R. Eugene Turner, D E. Van, H J. Windt

Faculty Publications

Coastal ecosystems are increasingly dominated by humans. Consequently, the human dimensions of sustainability science have become an integral part of emerging coastal governance and management practices. But if we are to avoid the harsh lessons of land management, coastal decision makers must recognize that humans are one of the more coastally dependent species in the biosphere. Management responses must therefore confront both the temporal urgency and the very real compromises and sacrifices that will be necessary to achieve a sustainable coastal ecosystem, one that is economically feasible, socially just, and ecologically sound.

Sap Flow Characteristics Of Neotropical Mangroves In Flooded And Drained Soils, Ken W. Krauss, P. Joy Young, Jim L. Chambers, Thomas W. Doyle, Robert R. Twilley

Faculty Publications

Effects of flooding on water transport in mangroves have previously been investigated in a few studies, most of which were conducted on seedlings in controlled settings. In this study, we used heat-dissipation sap probes to determine if sap flow (Js) attenuates with radial depth into the xylem of mature trees of three south Florida mangrove species growing in Rookery Bay. This was accomplished by inserting sap probes at multiple depths and monitoring diurnal flow. For most species and diameter size class combinations tested, Js decreased dramatically beyond a radial depth of 2 or 4 cm, with little sap flow beyond …

Sediments Tell The History Of Eutrophication And Hypoxia In The Northern Gulf Of Mexico, N.N. Rabalais, R.E. Turner, B.K.S. Gupta, E. Platon, M.L. Parsons

Faculty Publications

No abstract provided.

The Law And Economics Of Identity, Rafael Gely

Faculty Publications

A growing number of legal scholars have written about the demands that society and particular employers have placed on non-traditional employees to perform their identities, “or make themselves palatable” to their employers, by comporting with the criteria that the institution values. These authors have forcefully made the argument that some of these requirements are actually a form of class subordination; as a response, they argue for various forms of legal intervention.

A Window Into The Regulated Commons: The Takings Clause, Investment Security, And Sustainability, Josh Eagle

Faculty Publications

The holding of the U.S. Court of Appeals for the Federal Circuit in American Pelagic Fishing Co. v. United States points to the conclusion that the government will almost never be liable, under the Takings Clause, when fisheries regulations reduce the value of commercial fishing permits, vessels, or gear. From the perspective of natural resource economics, this is a healthy result. Economists suggest that solving commons problems requires that natural resources be under the complete control of a sole owner who makes self-interested decisions about resource use, and if the Fifth Amendment required the government owner to compensate fishermen when …

The Mutual Fund Distribution Fee Mess, John P. Freeman

Faculty Publications

No abstract provided.

Phenotypic Plasticity May Facilitate Invasion By Aegilops Triuncialis, Andrew R. Dyer

Faculty Publications

One great obstacle to understanding the invasion of nonnative species into native ecosystems is the lack of information on the population biology of the invading species. In particular, morphological and physiological adaptations and potential for phenotypic plasticity will strongly influence a species’ ability to persist and spread in newly invaded ecosystems. Phenotypic plasticity can buffer populations from selection thereby allowing them to survive the establishment phase of the invasion. The annual grass Aegilops triuncialis (Poaceae, Triticeae) has become highly invasive in California (USA) and provides an opportunity to investigate the importance of phenotypic plasticity to persistence and spread in new …

The African Lungfish (Protopterus Dolloi): Ionoregulation And Osmoregulation In A Fish Out Of Water, Michael P. Wilkie, Tammie P. Morgan, Fernando Galvez, Richard W. Smith, Makiko Kajimura, Yuen K. Ip, Chris M. Wood

Faculty Publications

Although urea production and metabolism in lungfish have been thoroughly studied, we have little knowledge of how internal osmotic and electrolyte balance are controlled during estivation or in water. We tested the hypothesis that, compared with the body surface of teleosts, the slender African lungfish (Protopterus dolloi) body surface was relatively impermeable to water, Na +, and Cl- due to its greatly reduced gills. Accordingly, we measured the tritiated water (3H-H2O) flux in P. dolloi in water and during air exposure. In water, 3H-H2O efflux was comparable with the lowest measurements reported in freshwater teleosts, with a rate constant (K) …

Sex, Seasonal, And Stress-Related Variations In Elasmobranch Corticosterone Concentrations, Charles A. Manire, L. E.L. Rasmussen, Karen P. Maruska, Timothy C. Tricas

Faculty Publications

Serum corticosterone was previously studied in numerous elasmobranch fishes (sharks, skates and rays), but the role of this steroid, widespread throughout many taxa, has yet to be defined. The goal of this study was to test whether corticosterone varied in response to acute and chronic capture stress, and across the reproductive cycle in the bonnethead shark, Sphyrna tiburo, and Atlantic stingray, Dasyatis sabina. Serum corticosterone in S. tiburo increased following capture and again 24 h post-capture, possibly caused by interference with 1α-hydroxycorticosterone, the primary stress hormone in elasmobranchs. Higher serum concentrations in males compared to females were observed in both …

Sex And Seasonal Co-Variation Of Arginine Vasotocin (Avt) And Gonadotropin-Releasing Hormone (Gnrh) Neurons In The Brain Of The Halfspotted Goby, Karen P. Maruska, Mindy H. Mizobe, Timothy C. Tricas

Faculty Publications

Gonadotropin-releasing hormone (GnRH) and arginine vasotocin (AVT) are critical regulators of reproductive behaviors that exhibit tremendous plasticity, but co-variation in discrete GnRH and AVT neuron populations among sex and season are only partially described in fishes. We used immunocytochemistry to examine sexual and temporal variations in neuron number and size in three GnRH and AVT cell groups in relation to reproductive activities in the halfspotted goby (Asterropteryx semipunctata). GnRH-immunoreactive (-ir) somata occur in the terminal nerve, preoptic area, and midbrain tegmentum, and AVT-ir somata within parvocellular, magnocellular, and gigantocellular regions of the preoptic area. Sex differences were found among all …

Decoupling Natural And Anthropogenic Fire Regimes: A Case Study In Everglades National Park, Florida, Matthew G. Slocum, William J. Platt, Brian Beckage, Bob Panko, James B. Lushine

Faculty Publications

Anthropogenic fire regimes obscure natural fire regimes, reducing the ability to manage fire-frequented habitats ecologically. To address this problem, we attempted to decouple natural and anthropogenic fire regimes by comparing them to seasonal climatic patterns and landscape characteristics in Everglades National Park (1948-1999). Of the total area burned by lightning fires, 57% resulted from ignitions seven days within onset of the wet season, 11% from ignitions starting 7-21 days before onset, and 36% from ignitions > 7 days after onset. In contrast, of the total area burned by incendiary fires, 89% resulted from ignitions > 7 days before onset, and 40% resulted …

Landscapes Of Power And Identity: Comparative Histories In The Sonoran Desert And The Forests Of Amazonia From Colony To Republic, Andrew Sluyter

Faculty Publications

No abstract provided.

Descriptions Of Soronia Complex (Coleoptera: Nitidulidae: Nitidulinae) Larvae Of New Zealand With Comments On Life History And Taxonomy, Chris Carlton, Richard A.B. Leschen

Faculty Publications

We provide the first descriptions of larvae of the nitidulid beetles Soronia oculata Reitter and Hisparonia hystrix (Sharp), compare them with similar larvae of other nitidulids, and comment on the utility of larval data in phylogenetic studies. Soronia oculata larvae are quite similar to many other larvae within the Soronia genus complex, but those of H. hystrix are distinctly different, namely by having an unfringed, spinose mandibular prostheca, striations of mola obscured by blunt teeth, and malar setae that are course and restricted to the distal half. This supports the recent transfer of the species to a monotypic genus. Larvae …

A National Putative Father Registry, Wells Conference On Adoption Law, Mary M. Beck

Faculty Publications

This Article will discuss the mechanics of putative father registries, review jurisdictional issues, analyze the policies behind their development, and review relevant case law over the last 5 years.

Undermining Individual And Collective Citizenship: The Impact Of Exclusion Laws On The African-American Community, S. David Mitchell

Faculty Publications

The purpose of this article is to expose felon exclusion laws as a method for undermining the individual and collective citizenship rights of the African-American community, and to call for their abolition.

The Role Of The Specific, Profilaggrin-Containing Keratohyalin Granules In The Developing Epidermis Of The Fetal Horse Hoof, Hermann H. Bragulla, Dominique G. Homberger

Faculty Publications

The adult equine hoof is subdivided into distinct segments with various keratinization modes. In the periople and bulbs of the heel, the epidermis forms a Stratum granulosum with basophilic keratohyalin granules during soft keratinization, whereas in the coronet, wall proper, sole, and frog, the epidermis undergoes hard keratinization by keratinizing and comifying without forming keratohyalin granules. The present study tests the hypothesis that the presence of specific (profilaggrin-containing) keratohyalin granules in the hoof epidermis is correlated with the water-binding capacity and mechanical properties of the hoof horn. To identify these specific profilaggrin-containing keratohyalin granules, tissue samples of fetal hooves were …

Life Without Water: Expression Of Plant Lea Genes By An Anhydrobiotic Arthropod, Steven C. Hand, Dana Jones, Michael A. Menze, Trudy L. Witt

Faculty Publications

Anhydrobiotic animals protect cellular architecture and metabolic machinery in the dry state, yet the molecular repertoire supporting this profound dehydration tolerance is not fully understood. For the desiccation-tolerant crustacean, Artemia franciscana, we report differential expression of two distinct mRNAs encoding for proteins that share sequence similarities and structural features with late-embryogenesis abundant (LEA) proteins originally discovered in plants. Bioinformatic analyses support assignment of the LEA proteins from A. franciscana to group 3. This eucoelomate species is the most highly evolved animal for which LEA gene expression has been reported. It is becoming clear that an ensemble of micromolecules and macromolecules …

Microbial Carbon Monoxide Consumption In Salt Marsh Sediments, Gary M. King

Faculty Publications

We have examined sediments from a fringing salt marsh in Maine to further understand marine CO metabolism, about which relatively little is known. Intact cores from the marsh emitted CO during dark oxic incubations, but emission rates were significantly higher during anoxic incubations, which provided evidence for simultaneous production and aerobic consumption in surface sediments. CO emission rates were also elevated when cores were exposed to light, which indicated that photochemical reactions play a role in CO production. A kinetic analysis of marsh surface sediments yielded an apparent Km of about 82 ppm, which exceeded values reported for well-aerated soils …

Biology And Host Specificity Of Gall-Inducing Acythopeus Burkhartorum (Coleoptera: Curculionidae), A Biological-Control Agent For The Invasive Weed Coccinia Grandis (Cucurbitaceae) In Guam And Saipan, Anantanarayanan Raman, Zerlene T. Cruz, Rangaswamy Muniappan, Gadi V.P. Reddy

Faculty Publications

An introduced cucurbit Coccinia grandis (Linnaeus) Voigt has grown into problem proportions in Hawaii and the Pacific islands of Guam and Saipan. The biology of Acythopeus burkhartorum OBrien, 1998, a potential biological-control agent of C. grandis, has been described. By inducing the gall a sink for nutrients and by deriving nutrition, A. burkhartorum places C. grandis under stress. Especially during the late larval stage, the weevil displays an unusual behaviour of shredding dry gall tissues with its mandibles to prepare the pupal case and using the shredded sclerenchyma fibres to fill the open and cut ends of the pupal case. …

Developing Children's Interest In Reading, Suzanne Marie Stauffer

Faculty Publications

No abstract provided.

On The Stability Of Periodic Solutions In The Perturbed Chemostat, Frédéric Mazenc, Michael Malisoff, Patrick De Leenheer

Faculty Publications

We study the chemostat model for one species competing for one nutrient using a Lyapunov-type analysis. We design the dilution rate function so that all solutions of the chemostat converge to a prescribed periodic solution. In terms of chemostat biology, this means that no matter what positive initial levels for the species concentration and nutrient are selected, the long-term species concentration and substrate levels closely approximate a prescribed oscillatory behavior. This is significant because it reproduces the realistic ecological situation where the species and substrate concentrations oscillate. We show that the stability is maintained when the model is augmented by …

Supervised Learning Method For The Prediction Of Subcellular Localization Of Proteins Using Amino Acid And Amino Acid Pair Composition, Tanwir Habib, Chaoyang Zhang, Jack Y. Yang, Mary Qu Yang, Youping Deng

Faculty Publications

Background

Occurrence of protein in the cell is an important step in understanding its function. It is highly desirable to predict a protein's subcellular locations automatically from its sequence. Most studied methods for prediction of subcellular localization of proteins are signal peptides, the location by sequence homology, and the correlation between the total amino acid compositions of proteins. Taking amino-acid composition and amino acid pair composition into consideration helps improving the prediction accuracy.

Results

We constructed a dataset of protein sequences from SWISS-PROT database and segmented them into 12 classes based on their subcellular locations. SVM modules were trained to …

Density, Territory Size, And Long-Term Spatial Dynamics Of A Guild Of Terrestrial Insectivorous Birds Near Manaus, Brazil, Philip C. Stouffer

Faculty Publications

From 1994 to 2003, I annually surveyed terrestrial insectivorous birds in a 100-ha plot within continuous rainforest near Manaus, Brazil. I used spot-map registrations and radiotagged birds to estimate territory size and density on the plot for 13 species. As in the few previous studies of Amazonian birds, territory sizes were large (mean = 13.0 ha) and densities were low (mean = 3.4 pairs per 100 ha). The most common species, Formicarius colma, was the only species with >10 pairs per 100 ha, and one of four species (with Myrmeciza ferruginea, Conopophaga aurita, and Corythopis torquaius) to have territories of …