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Coral Reef Genomics: Developing tools for functional genomics ofcoral symbiosis (open access)

Coral Reef Genomics: Developing tools for functional genomics ofcoral symbiosis

Symbioses between cnidarians and dinoflagellates in the genus Symbiodinium are widespread in the marine environment. The importance of this symbiosis to reef-building corals and reef nutrient and carbon cycles is well documented, but little is known about the mechanisms by which the partners establish and regulate the symbiosis. Because the dinoflagellate symbionts live inside the cells of their host coral, the interactions between the partners occur on cellular and molecular levels, as each partner alters the expression of genes and proteins to facilitate the partnership. These interactions can examined using high-throughput techniques that allow thousands of genes to be examined simultaneously. We are developing the groundwork so that we can use DNA microarray profiling to identify genes involved in the Montastraea faveolata and Acropora palmata symbioses. Here we report results from the initial steps in this microarray initiative, that is, the construction of cDNA libraries from 4 of 16 target stages, sequencing of 3450 cDNA clones to generate Expressed Sequenced Tags (ESTs), and annotation of the ESTs to identify candidate genes to include in the microarrays. An understanding of how the coral-dinoflagellate symbiosis is regulated will have implications for atmospheric and ocean sciences, conservation biology, the study and diagnosis of …
Date: March 1, 2005
Creator: Schwarz, Jodi; Brokstein, Peter; Manohar, Chitra; Coffroth, MaryAlice; Szmant, Alina & Medina, Monica
System: The UNT Digital Library
Measurement of the resonance parameters of the chi(1)(1**3P(1)) and chi(2)(1**3P(2)) states of charmonium formed in antiproton-proton annihilations (open access)

Measurement of the resonance parameters of the chi(1)(1**3P(1)) and chi(2)(1**3P(2)) states of charmonium formed in antiproton-proton annihilations

The authors have studied the {sup 3}P{sub J} ({chi}{sub e}) states of charmonium in formation by antiproton-proton annihilations in experiment E835 at the Fermilab Antiproton Source. The authors report new measurements of the mass, width, and B({chi}{sub cJ} {yields} {bar p}p) x {Lambda}({chi}{sub eJ} {yields} J/{psi} + anything) for the {chi}{sub c1} and {chi}{sub c2} by means of the inclusive reaction {bar p}p {yields} {chi}{sub cJ} {yields} J/{psi} + anything {yields} (e{sup +}e{sup -}) + anything. Using the subsample of events where {chi}{sub cJ} {yields} {gamma} + J/{psi} {yields} {gamma} + (e{sup +}e{sup -}) is fully reconstructed, we derive B({chi}{sub cJ} {yields} {bar p}p) x {Lambda}({chi}{sub cJ} {yields} J/{psi} + {gamma}). They summarize the results of the E760 (updated) and E835 measurements of mass, width and B({chi}{sub cJ} {yields} {bar p}p){Lambda}({chi}{sub cJ} {yields} J/{psi} + {gamma}) (J = 0,1,2) and discuss the significance of these measurements.
Date: March 1, 2005
Creator: Andreotti, M.; Bagnasco, S.; Baldini, W.; Bettoni, D.; Borreani, G.; Buzzo, A. et al.
System: The UNT Digital Library
Intrabeam scattering formulas for fast numerical evaluation (open access)

Intrabeam scattering formulas for fast numerical evaluation

Expressions for small-angle multiple intrabeam scattering (IBS) emittance growth rates are normally expressed through integrals, which require a numeric evaluation at various locations of the accelerator lattice. In this paper, I demonstrate that the IBS growth rates can be presented in closed-form expressions with the help of the so-called symmetric elliptic integral. This integral can be evaluated numerically by a very efficient recursive method by employing the duplication theorem. Several examples of IBS rates for a smooth-lattice approximation, equal transverse temperatures and plasma temperature relaxation are given.
Date: March 1, 2005
Creator: Nagaitsev, Sergei
System: The UNT Digital Library
Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project: Data Analysis Overview; Preprint (open access)

Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project: Data Analysis Overview; Preprint

Paper for the 2005 National Hydrogen Association conference provides an overview of the U.S. Department of Energy's Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project.
Date: March 1, 2005
Creator: Welch, C.; Wipke, K.; Gronich, S. & Garbak, J.
System: The UNT Digital Library
The Improbability scale (open access)

The Improbability scale

The Improbability Scale (IS) is proposed as a way of communicating to the general public the improbability (and by implication, the probability) of events predicted as the result of scientific research. Through the use of the Improbability Scale, the public will be able to evaluate more easily the relative risks of predicted events and draw proper conclusions when asked to support governmental and public policy decisions arising from that research.
Date: March 1, 2005
Creator: Ritchie, David J.
System: The UNT Digital Library
Biomechanics of Wheat/Barley Straw and Corn Stover (open access)

Biomechanics of Wheat/Barley Straw and Corn Stover

The lack of understanding of the mechanical characteristics of cellulosic feedstocks is a limiting factor in economically collecting and processing crop residues, primarily wheat and barley stems and corn stover. Several testing methods, including compression, tension, and bend have been investigated to increase our understanding of the biomechanical behavior of cellulosic feedstocks. Biomechanical data from these tests can provide required input to numerical models and help advance harvesting, handling, and processing techniques. In addition, integrating the models with the complete data set from this study can identify potential tools for manipulating the biomechanical properties of plant varieties in such a manner as to optimize their physical characteristics to produce higher value biomass and more energy efficient harvesting practices.
Date: March 1, 2005
Creator: Wright, Christopher T.; Pryfogle, Peter A.; Stevens, Nathan A.; Steffler, Eric D.; Hess, J. Richard & Ulrich, Thomas H.
System: The UNT Digital Library
Regulatory role of AINTEGUMENTA in organ initiation and growth (open access)

Regulatory role of AINTEGUMENTA in organ initiation and growth

Although several members of the plant-specific AP2/ERF family of transcription factors are important developmental regulators, many genes in this large protein family remain uncharacterized. Here, we present a phylogenetic analysis of the18 genes that make up the AP2 subgroup of this family. We report expression analyses of seven Arabidopsis genes most closely related to the floral development gene AINTEGUMENTA and show that all AINTEGUMENTA-like (AIL) genes are transcribed in multiple tissues during development. They are expressed primarily in young actively dividing tissues of a plant and not in mature leaves or stems. The spatial distribution of AIL5, AIL6, and AIL7 mRNA in inflorescences was characterized by in situ hybridization. Each of these genes is expressed in a spatially and temporally distinct pattern within inflorescence meristems and flowers. Ectopic expression of AIL5 resulted in a larger floral organ phenotype, similar to that resulting from ectopic expression of ANT. Our results are consistent with AIL genes having roles in specification of meristematic or division-competent states.
Date: March 1, 2005
Creator: Krizek, Beth Allyn & Lebioda, Lukasz
System: The UNT Digital Library
Overview of the Environmental and Water Resources Institute's "Guidelines For Integrated Water Resources Management" Project (open access)

Overview of the Environmental and Water Resources Institute's "Guidelines For Integrated Water Resources Management" Project

Integrated Water Resources Management is a systematic approach to optimizing our understanding, control and management of water resources within a basin to meet multiple objectives. Recognition of the need for integrating water resources within basins is not unique to the Environmental and Water Resources Institute’s Integrated Water Resources Management Task Committee. Many individuals, governments and other organizations have attempted to develop holistic water resources management programs. In some cases, the results have been very effective and in other cases, valiant attempts have fallen far short of their initial goals. The intent of this Task Committee is to provide a set of guidelines that discusses the concepts, methods and tools necessary for integrating and optimizing the management of the physical resources and to optimize and integrate programs, organizations, infrastructure, and socioeconomic institutions into comprehensive water resources management programs.
Date: March 1, 2005
Creator: Sehlke, Gerald
System: The UNT Digital Library
Testing of a Catalytic Partial Oxidation Diesel Reformer with a Solid Oxide Fuel Cell System (open access)

Testing of a Catalytic Partial Oxidation Diesel Reformer with a Solid Oxide Fuel Cell System

Rural Alaska currently uses diesel generator sets to produce much of its power. The high energy content of diesel (i.e. ~140,000 BTU per gallon) makes it the fuel of choice because this reduces the volume of fuel that must be transported, stored, and consumed in generating the power. There is an existing investment in infrastructure for the distribution and use of diesel fuel. Problems do exist, however, in that diesel generators are not very efficient in their use of diesel, maintenance levels can be rather high as systems age, and the environmental issues related to present diesel generators are of concern. The Arctic Energy Technology Development Laboratory at the University of Alaska -- Fairbanks is sponsoring a project to address the issues mentioned above. The project takes two successful systems, a diesel reformer and a tubular solid oxide fuel cell unit, and jointly tests those systems with the objective of producing a for-purpose diesel fueled solid oxide fuel cell system that can be deployed in rural Alaska. The reformer will convert the diesel to a mixture of carbon monoxide and hydrogen that can be used as a fuel by the fuel cell. The high temperature nature of the solid oxide …
Date: March 1, 2005
Creator: Frost, Lyman; Carrington, Bob; McKain, Rodger & Witmer, Dennis
System: The UNT Digital Library
Shape Optimization of Swimming Sheets (open access)

Shape Optimization of Swimming Sheets

The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical …
Date: March 1, 2005
Creator: Wilkening, J. & Hosoi, A.E.
System: The UNT Digital Library
Review of Residential Ventilation Technologies (open access)

Review of Residential Ventilation Technologies

This paper reviews current and potential ventilation technologies for residential buildings in North America and a few in Europe. The major technologies reviewed include a variety of mechanical systems, natural ventilation, and passive ventilation. Key parameters that are related to each system include operating costs, installation costs, ventilation rates, heat recovery potential. It also examines related issues such as infiltration, duct systems, filtration options, noise, and construction issues. This report describes a wide variety of systems currently on the market that can be used to meet ASHRAE standard 62.2. While these systems generally fall into the categories of supply, exhaust or balanced, the specifics of each system are driven by concerns that extend beyond those in the standard and are discussed. Some of these systems go beyond the current standard by providing additional features (such as air distribution or pressurization control). The market will decide the immediate value of such features, but ASHRAE may wish to consider modifications to the standard in the future.
Date: March 1, 2005
Creator: Russell, Marion L.; Sherman, Max H. & Rudd, Armin
System: The UNT Digital Library
Determination of Band Curvatures by Angle-resolved Two-photonPhotoemission in thin films of C(60) on Ag(111) (open access)

Determination of Band Curvatures by Angle-resolved Two-photonPhotoemission in thin films of C(60) on Ag(111)

The thickness-dependent interfacial band structure wasdetermined for thin films of Co(6) on Ag(111) by angle-resolvedtwo-photon photoemission spectroscopy.
Date: March 1, 2005
Creator: Shipman, Steven T.; Szymanski, Paul; Garrett-Roe, Sean; Yang,Aram; Strader, Matthew L. & Harris, Charles B.
System: The UNT Digital Library
Physics-Based Prognostics for Optimizing Plant Operation (open access)

Physics-Based Prognostics for Optimizing Plant Operation

Scientists at the Pacific Northwest National Laboratory (PNNL) have examined the necessity for optimization of energy plant operation using 'DSOM{reg_sign}'--Decision Support Operation and Maintenance and this has been deployed at several sites. This approach has been expanded to include a prognostics components and tested on a pilot scale service water system, modeled on the design employed in a nuclear power plant. A key element in plant optimization is understanding and controlling the aging process of safety-specific nuclear plant components. This paper reports the development and demonstration of a physics-based approach to prognostic analysis that combines distributed computing, RF data links, the measurement of aging precursor metrics and their correlation with degradation rate and projected machine failure.
Date: March 1, 2005
Creator: Bond, Leonard J. & Jarrell, Don B.
System: The UNT Digital Library
Preliminary Measurements From A New Flat Plate Facility For Aerodynamic Research (open access)

Preliminary Measurements From A New Flat Plate Facility For Aerodynamic Research

This paper details the design and preliminary measurements used in the characterisation of a new flat plate research facility. The facility is designed specifically to aid in the understanding of entropy generation throughout the boundary layer with special attention given to non-equilibrium flows. Hot-wire measurements were obtained downstream of two turbulence generating grids. The turbulence intensity, integral and dissipation length scale ranges measured are 1.6%-7%, 5mm-17mm and 0.7mm-7mm, respectively. These values compared well to existing correlations. The flow downstream of both grids was found to be homogenous and isotropic. Flow visualisation is employed to determine aerodynamic parameters such as flow 2-dimensionality and the effect of the flap angle on preventing separation at the leading edge. The flow was found to be 2-dimensional over all measurement planes. The non-dimensional pressure distribution of a modern turbine blade suction surface is simulated on the flat plate through the use of a variable upper wall. The Reynolds number range based on wetted plate length and inlet velocity is 70,000-4,000,000.
Date: March 1, 2005
Creator: McEligot, D. M.; Nigg, D. W.; Walsh, E. J.; Hernon, D. & Davies, M.R.D.
System: The UNT Digital Library
Duct Tape and Sealant Performance (open access)

Duct Tape and Sealant Performance

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Date: March 1, 2005
Creator: Walker, Iain S. & Sherman, Max H.
System: The UNT Digital Library
Methane Hydrate Formation and Dissocation in a Partially Saturated Sand--Measurements and Observations (open access)

Methane Hydrate Formation and Dissocation in a Partially Saturated Sand--Measurements and Observations

We performed a sequence of tests on a partially water-saturated sand sample contained in an x-ray transparent aluminum pressure vessel that is conducive to x-ray computed tomography (CT) observation. These tests were performed to gather data for estimation of thermal properties of the sand/water/gas system and the sand/hydrate/water/gas systems, as well as data to evaluate the kinetic nature of hydrate dissociation. The tests included mild thermal perturbations for the estimation of the thermal properties of the sand/water/gas system, hydrate formation, thermal perturbations with hydrate in the stability zone, hydrate dissociation through thermal stimulation, additional hydrate formation, and hydrate dissociation through depressurization with thermal stimulation. Density changes throughout the sample were observed as a result of hydrate formation and dissociation, and these processes induced capillary pressure changes that altered local water saturation.
Date: March 1, 2005
Creator: Kneafsey, Timothy J.; Tomutsa, Liviu; Moridis, George J.; Seol, Yongkoo; Freifeld, Barry; Taylor, Charles E. et al.
System: The UNT Digital Library
Improving Indoor Environmental Quality And Energy Performance of Modular Classroom HVAC Systems (open access)

Improving Indoor Environmental Quality And Energy Performance of Modular Classroom HVAC Systems

The factory-built relocatable classroom (RC) is a dominant force in the school facility construction industry in the US and elsewhere. it is estimated that there are approximately 650,000 RCs currently occupied in the US, housing about 16 million students. RCs receive public attention due to complaints about poor indoor environmental quality (IEQ). Both measured data and anecdotal evidence in California have suggested excessive acoustical noise from heating, ventilation, and air conditioning (HVAC) equipment as a central factor leading to degraded IEQ. In the US, RCs are typically equipped with unitary exterior wall-mount HVAC systems, and interior acoustical noise due to structural and airborne transmission can reach levels of about 58dB(A) with compressor cycling, under unoccupied conditions. Due to these noise levels, teachers often simply choose to turn off the HVAC, leading to inadequate ventilation, as well as poor thermal conditioning, and thus to poor indoor air quality. Elevated levels of carbon dioxide and volatile organic compounds including formaldehyde are common. They discuss the acoustic component of the efforts to develop and test energy efficient HVAC systems that address the ventilation, controls, and acoustic requirements necessary to ensure high quality indoor environments in RCs.
Date: March 1, 2005
Creator: Apte, Michael G.; Spears, Michael; Lai, Chi-Ming & Shendell, Derek G.
System: The UNT Digital Library
Spatial and temporal ecology of eastern spadefoot toads on a Florida landscape. (open access)

Spatial and temporal ecology of eastern spadefoot toads on a Florida landscape.

Effective amphibian conservation must consider population and landscape processes, but information at multiple scales is rare. We explore spatial and temporal patterns of breeding and recruitment by Eastern Spadefoot Toads (Scaphiopus holbrookii), using 9 years of data from continuous monitoring with drift fences and pitfall traps at 8 ephemeral ponds in longleaf pine-wiregrass sandhills. Breeding events (>25 adults at a pond within a month) occurred 23 times on nine occasions at seven of the eight study ponds, but substantial recruitment(>100 metamorphs) followed only five events. Recruitment ranged from 0-4,648 among ponds. Only four ponds functioned as population ''sources'', but only during some years. The other ponds, and even ''source'' ponds during some years, functioned either as ''sinks'', where breeding occurred with no resulting recruitment, or were not used at all for breeding. Most recruitment occurred during four years. Recruitment was correlated with adult breeding effort, but only during some years. Recaptures were rare, and inter-pond exchange of adults was minimal and short-distance (< 130 m; 1 was 416 m). Most (83.5%) individuals captured were metamorphs, and 15.9% were > 51 mm (est. > 4 years). We conservatively estimated a 7-year lifespan. Adult ''population'' trends clearly reflected breeding effort rather than …
Date: March 1, 2005
Creator: Greenberg, Cathyrn, H. & Tanner, George, W.
System: The UNT Digital Library
What's Up With Duct Tape (open access)

What's Up With Duct Tape

Recent research suggests that almost any tape can be made to work for a core-to-collar joint when perfectly applied. Given all the better choices available and all the problems that can and do occur in the field, we would not recommend that cloth-backed (natural) rubber-adhesive tapes be used, unless they can pass a suitable E2343 test. If visual degradation is an important factor, Oriented Polypropylene (OPP) and cloth-backed tapes should be avoided. While tapes that fail usually show visual degradation, the converse is not always true. We speculate, however, that visually degraded tapes are more likely to be susceptible to damage from vibration and other mechanical stresses. Conventional nylon straps are quite prone to fail at higher temperatures, but no systematic studies have yet been done across product classes. UL has proposed a new standard for straps, but the protocol for the current UL test does not, however, suggest that it would be a good indicator of durability. Products meeting the new UL standard for straps should be independently tested for the failure modes observed in the field and laboratory to determine if that test is a reasonable indicator of durability. Until a suitable test for strap durability exists, they …
Date: March 1, 2005
Creator: Walker, Iain S. & Sherman, Max H.
System: The UNT Digital Library
Real Options Valuation of U.S. Federal Renewable Energy Research,Development, Demonstration, and Deployment (open access)

Real Options Valuation of U.S. Federal Renewable Energy Research,Development, Demonstration, and Deployment

Benefits analysis of US Federal government funded research, development, demonstration, and deployment (RD3) programs for renewable energy (RE) technology improvement typically employs a deterministic forecast of the cost and performance of renewable and nonrenewable fuels. The benefits estimate for a program derives from the difference between two forecasts, with and without the RD3 in place. The deficiencies of the current approach are threefold: (1) it does not consider uncertainty in the cost of non-renewable energy (NRE), and the option or insurance value of deploying RE if and when NRE costs rise; (2) it does not consider the ability of the RD3 manager to adjust the RD3 effort to suit the evolving state of the world, and the option value of this flexibility; and (3) it does not consider the underlying technical risk associated with RD3, and the impact of that risk on the programs optimal level of RD3 effort. In this paper, a rudimentary approach to determining the option value of publicly funded RE RD3 is developed. The approach seeks to tackle the first deficiency noted above by providing an estimate of the options benefit of an RE RD3 program in a future with uncertain NRE costs.While limited by severe …
Date: March 1, 2005
Creator: Siddiqui, Afzal S.; Marnay, Chris & Wiser, Ryan H.
System: The UNT Digital Library
Integration of Ion Implantation with Scanning ProbeAlignment (open access)

Integration of Ion Implantation with Scanning ProbeAlignment

We describe a scanning probe instrument which integrates ion beams with imaging and alignment functions of a piezo resistive scanning probe in high vacuum. Energetic ions (1 to a few hundred keV) are transported through holes in scanning probe tips [1]. Holes and imaging tips are formed by Focused Ion Beam (FIB) drilling and ion beam assisted thin film deposition. Transport of single ions can be monitored through detection of secondary electrons from highly charged dopant ions (e. g., Bi{sup 45+}) enabling single atom device formation. Fig. 1 shows SEM images of a scanning probe tip formed by ion beam assisted Pt deposition in a dual beam FIB. Ion beam collimating apertures are drilled through the silicon cantilever with a thickness of 5 {micro}m. Aspect ratio limitations preclude the direct drilling of holes with diameters well below 1 {micro}m, and smaller hole diameters are achieved through local thin film deposition [2]. The hole in Fig. 1 was reduced from 2 {micro}m to a residual opening of about 300 nm. Fig. 2 shows an in situ scanning probe image of an alignment dot pattern taken with the tip from Fig. 1. Transport of energetic ions through the aperture in the scanning …
Date: March 1, 2005
Creator: Persaud, A.; Rangelow, I. W. & Schenkel, T.
System: The UNT Digital Library
Phenomenology beyond the standard model (open access)

Phenomenology beyond the standard model

An elementary review of models and phenomenology for physics beyond the Standard Model (excluding supersymmetry). The emphasis is on LHC physics. Based upon a talk given at the ''Physics at LHC'' conference, Vienna, 13-17 July 2004.
Date: March 1, 2005
Creator: Lykken, Joseph D.
System: The UNT Digital Library
Studies of NICADD Extruded Scintillator Strips (open access)

Studies of NICADD Extruded Scintillator Strips

About four hundred one meter long, 10 cm wide and 5 mm thick extruded scintillating strips were measured at four different points. The results of measurements strip responses to a radioactive source {sup 90}Sr are provided, and details of strip choice, preparation, and method of measurement are included. This work was essential for prototyping a tail catcher and muon tracker for a future international electron positron linear collider detector.
Date: March 1, 2005
Creator: Dychkant, Alexandre & al., et
System: The UNT Digital Library
A New Milky Way dwarf galaxy in Ursa Major (open access)

A New Milky Way dwarf galaxy in Ursa Major

In this Letter, we report the discovery of a new dwarf satellite to the Milky Way, located at ({alpha}{sub 2000}, {delta}{sub 2000}) = (158.72,51.92) in the constellation of Ursa Major. This object was detected as an overdensity of red, resolved stars in Sloan Digital Sky Survey data. The color-magnitude diagram of the Ursa Major dwarf looks remarkably similar to that of Sextans, the lowest surface brightness Milky Way companion known, but with approximately an order of magnitude fewer stars. Deeper follow-up imaging confirms this object has an old and metal-poor stellar population and is {approx} 100 kpc away. We roughly estimate M{sub V} = -6.75 and r{sub 1/2} = 250 pc for this dwarf. Its luminosity is several times fainter than the faintest known Milky Way dwarfs. However, its physical size is typical for dSphs. Even though its absolute magnitude and size are presently quite uncertain, Ursa Major is likely the lowest luminosity and lowest surface brightness galaxy yet known.
Date: March 1, 2005
Creator: Willman, Beth; Dalcanton, Julianne J.; Martinez-Delgado, David; West, Andrew A.; Blanton, Michael R.; Hogg, David W. et al.
System: The UNT Digital Library