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ASM News Volume 71 Number 9, 2005 (open access)

ASM News Volume 71 Number 9, 2005

Genetic exchanges among prokaryotes, formerly considered only a marginal phenomenon, increasingly are being viewed as profoundly affecting evolution. Indeed, some researchers argue for utterly revamping our concept of microbial speciation and phylogeny by replacing the traditional ''tree'' with a newer ''net'' to account for these horizontal transfers of genes. This conceptual ferment is occurring while molecular biologists reveal how horizontal gene transfers occur even as microbes protect the integrity of their genomes. Other studies reveal the number and diversity and abundance of genetic elements that mediate horizontal gene transfers (HGTs) or facilitate genome rearrangements, deletions, and insertions. Taken together, this information suggests that microbial communities collectively possess a dynamic gene pool, where novel genetic combinations act as a driving force in genomic innovation, compensating individual microbial species for their inability to reproduce sexually. These microbial genomic dynamics can present both environmental threats and promise to humans. One major threat, for example, comes from the spread of antibiotic resistance and virulence genes among pathogenic microbes. Another less-documented issue involves transgenic plants and animals, whose uses are being restricted because of concerns that genes may be transferred to untargeted organisms where they might cause harm. A possible benefit from HGT comes from …
Date: January 1, 2005
Creator: Smets, Tamar Barkay and Barth F.
Object Type: Article
System: The UNT Digital Library
Aspects of the Coriolis Interaction in U235 (open access)

Aspects of the Coriolis Interaction in U235

We have performed three separate experiments at LBNL's 88-Inch Cyclotron over a period of several years in which {sup 235}U (thick target) was Coulomb-excited. It involved stand-alone experiments with Gammasphere and with the 8PI Spectrometer using {sup 136}Xe beams at 720 MeV, and a CHICO-Gammasphere experiment with an {sup 40}Ar beam at 180 MeV. In addition to extending the known negative-parity bands to high spin, we have assigned levels in some seven positive-parity bands which are in some cases (e.g. [631]1/2, [624]7/2 and [622]5/2) strongly populated by E3 excitation. The CHICO data has been analyzed to extract E2 and E3 matrix elements from the observed yields. Additionally, many E1 and M1 matrix elements could be extracted from the {gamma}-ray branching ratios.
Date: January 1, 2005
Creator: Ward, D.; Clark, R. M.; Cromaz, M.; Deleplanque, M. A.; Diamond, R. M.; Fallon, P. et al.
Object Type: Article
System: The UNT Digital Library
Assessing the Potential for Renewable Energy on National Forest System Lands (open access)

Assessing the Potential for Renewable Energy on National Forest System Lands

This technical report and CD for the U.S. Department of Agriculture, Forest Service (USFS), evaluates the potential for renewable energy resource development on National Forest System (NFS) lands. USFS can use the report findings to consider potential for development of solar and wind energy resources on NFS lands, in land management decisions. The Geographical Information System (GIS) based analysis resulted in the following findings: (1) Ninety-nine National Forest Units have high potential for power production from one or more of these solar and wind energy sources; and (2) Twenty National Forest Units in nine states have high potential for power production from two or more of these solar and wind energy sources.
Date: January 1, 2005
Creator: unknown
Object Type: Book
System: The UNT Digital Library
Assessment of disinfectants in explosive destruction system for biological agent destruction : LDRD final report FY04. (open access)

Assessment of disinfectants in explosive destruction system for biological agent destruction : LDRD final report FY04.

Treatment systems that can neutralize biological agents are needed to mitigate risks from novel and legacy biohazards. Tests with Bacillus thuringiensis and Bacillus steurothemophilus spores were performed in a 190-liter, 1-112 lb TNT equivalent rated Explosive Destruction System (EDS) system to evaluate its capability to treat and destroy biological agents. Five tests were conducted using three different agents to kill the spores. The EDS was operated in steam autoclave, gas fumigation and liquid decontamination modes. The first three tests used EDS as an autoclave, which uses pressurized steam to kill the spores. Autoclaving was performed at 130-140 deg C for up to 2-hours. Tests with chlorine dioxide at 750 ppm concentration for 1 hour and 10% (vol) aqueous chlorine bleach solution for 1 hour were also performed. All tests resulted in complete neutralization of the bacterial spores based on no bacterial growth in post-treatment incubations. Explosively opening a glass container to expose the bacterial spores for treatment with steam was demonstrated and could easily be done for chlorine dioxide gas or liquid bleach.
Date: January 1, 2005
Creator: Simmons, Blake Alexander; Didlake, John E. Jr.; Bradshaw, Robert W.; Crooker, Paul J. & Buffleben, George M.
Object Type: Report
System: The UNT Digital Library
Atmospheric Emitted Radiance Interferometer (AERI) Handbook (open access)

Atmospheric Emitted Radiance Interferometer (AERI) Handbook

The atmospheric emitted radiance interferometer (AERI) measures the absolute infrared (IR) spectral radiance (watts per square meter per steradian per wavenumber) of the sky directly above the instrument. The spectral measurement range of the instrument is 3300 to 520 wavenumbers (cm-1) or 3-19.2 microns for the normal-range instruments and 3300 to 400 cm-1 or 3-25 microns, for the extended-range polar instruments. Spectral resolution is 1.0 cm-1. Instrument field-of-view is 1.3 degrees. A calibrated sky radiance spectrum is produced every 8 minutes in normal mode and every minute in rapid sampling mode. The actual sample scan time is 20-30 sec in rapid sampling mode with periodic gaps when the instrument is looking at the blackbodies. Rapid sampling will become available in all AERIs. Rapid sampling time will eventually be reduced to data every 20 seconds. The AERI data can be used for 1) evaluating line-by-line radiative transport codes, 2) detecting/quantifying cloud effects on ground-based measurements of infrared spectral radiance (and hence is valuable for cloud property retrievals), and 3) calculating vertical atmospheric profiles of temperature and water vapor and the detection of trace gases.
Date: January 1, 2005
Creator: Demirgian, J. & Dedecker, R.
Object Type: Report
System: The UNT Digital Library
Automated visual direction : LDRD 38623 final report. (open access)

Automated visual direction : LDRD 38623 final report.

Mobile manipulator systems used by emergency response operators consist of an articulated robot arm, a remotely driven base, a collection of cameras, and a remote communications link. Typically the system is completely teleoperated, with the operator using live video feedback to monitor and assess the environment, plan task activities, and to conduct the operations via remote control input devices. The capabilities of these systems are limited, and operators rarely attempt sophisticated operations such as retrieving and utilizing tools, deploying sensors, or building up world models. This project has focused on methods to utilize this video information to enable monitored autonomous behaviors for the mobile manipulator system, with the goal of improving the overall effectiveness of the human/robot system. Work includes visual servoing, visual targeting, utilization of embedded video in 3-D models, and improved methods of camera utilization and calibration.
Date: January 1, 2005
Creator: Anderson, Robert J.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 27, Ed. 1 Saturday, January 1, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 27, Ed. 1 Saturday, January 1, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: January 1, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam-beam effects in the Tevatron (open access)

Beam-beam effects in the Tevatron

The Tevatron in Collider Run II (2001-present) is operating with 6 times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Electromagnetic long-range and head-on interactions of high intensity proton and antiproton beams have been significant sources of beam loss and lifetime limitations. We present observations of the beam-beam phenomena in the Tevatron and results of relevant beam studies. We analyze the data and various methods employed in operations, predict the performance for planned luminosity upgrades, and discuss ways to improve it.
Date: January 1, 2005
Creator: Shiltsev, V.; Alexahin, Y.; Lebedev, V.; Lebrun, P.; Moore, R. S.; Sen, T. et al.
Object Type: Article
System: The UNT Digital Library
Beam-beam simulations of hadron colliders (open access)

Beam-beam simulations of hadron colliders

None
Date: January 1, 2005
Creator: Sen, Tanaji
Object Type: Article
System: The UNT Digital Library
The Beam_Optics at the Extraction Region of SNS ring; Revisited (open access)

The Beam_Optics at the Extraction Region of SNS ring; Revisited

N/A
Date: January 1, 2005
Creator: Tsoupas, N.; Hemmer, M.; Lee, Y. Y.; Pai, C. I.; Rank, J.; Mi, J. L. et al.
Object Type: Report
System: The UNT Digital Library
Biology and management of insect pests in North American intensively managed hardwood forest systems. (open access)

Biology and management of insect pests in North American intensively managed hardwood forest systems.

Annu. Rev. Entomol. 50:1-29. Abstract Increasing demand for wood and wood products is putting stress on traditional forest production areas, leading to long-term economic and environmental concerns. Intensively managed hardwood forest systems (IMHFS), grown using conventional agricultural as well as forestry methods, can help alleviate potential problems in natural forest production areas. Although IMHFS can produce more biomass per hectare per year than natural forests, the ecologically simplified, monocultural systems may greatly increase the crops susceptibility to pests. Species in the genera Populus and Salix comprise the greatest acreage in IMHFS in North America, but other species, including Liquidambar styracifua and Platanus occidentalis, are also important. We discuss life histories, realized and potential damage, and management options for the most economically infuential pests that affect these hardwood species. The substantial inherent challenges associated with pest management in the monocultural environments created by IMHFS are reviewed. Finally, we discuss ways to design IMHFS that may reduce their susceptibility to pests, increase their growth and productivity potential, and create a more sustainable environment.
Date: January 1, 2005
Creator: Coyle, David R.; Nebeker, T., E.; Hart, E., R. & Mattson, W., J.
Object Type: Article
System: The UNT Digital Library
Biomolecular decision-making process for self assembly. (open access)

Biomolecular decision-making process for self assembly.

The brain is often identified with decision-making processes in the biological world. In fact, single cells, single macromolecules (proteins) and populations of molecules also make simple decisions. These decision processes are essential to survival and to the biological self-assembly and self-repair processes that we seek to emulate. How do these tiny systems make effective decisions? How do they make decisions in concert with a cooperative network of other molecules or cells? How can we emulate the decision-making behaviors of small-scale biological systems to program and self-assemble microsystems? This LDRD supported research to answer these questions. Our work included modeling and simulation of protein populations to help us understand, mimic, and categorize molecular decision-making mechanisms that nonequilibrium systems can exhibit. This work is an early step towards mimicking such nanoscale and microscale biomolecular decision-making processes in inorganic systems.
Date: January 1, 2005
Creator: Osbourn, Gordon Cecil
Object Type: Report
System: The UNT Digital Library
Building America Research Benchmark Definition, Version 3.1, Updated July 14, 2004 (open access)

Building America Research Benchmark Definition, Version 3.1, Updated July 14, 2004

To track progress toward aggressive multi-year whole-house energy savings goals of 40-70% and onsite power production of up to 30%, the U.S. Department of Energy (DOE) Residential Buildings Program and the National Renewable Energy Laboratory (NREL) developed the Building America Research Benchmark in consultation with the Building America industry teams. The Benchmark is generally consistent with mid-1990s standard practice, as reflected in the Home Energy Rating System (HERS) Technical Guidelines (RESNET 2002), with additional definitions that allow the analyst to evaluate all residential end-uses, an extension of the traditional HERS rating approach that focuses on space conditioning and hot water. A series of user profiles, intended to represent the behavior of a ''standard'' set of occupants, was created for use in conjunction with the Benchmark.
Date: January 1, 2005
Creator: Hendron, R.
Object Type: Report
System: The UNT Digital Library
Calcine Waste Storage at the Idaho Nuclear Technology and Engineering Center (open access)

Calcine Waste Storage at the Idaho Nuclear Technology and Engineering Center

This report documents an inventory of calcined waste produced at the Idaho Nuclear Technology and Engineering Center during the period from December 1963 to May 2000. The report was prepared based on calciner runs, operation of the calcined solids storage facilities, and miscellaneous operational information that establishes the range of chemical compositions of calcined waste stored at Idaho Nuclear Technology and Engineering Center. The report will be used to support obtaining permits for the calcined solids storage facilities, possible treatment of the calcined waste at the Idaho National Engineering and Environmental Laboratory, and to ship the waste to an off-site facility including a geologic repository. The information in this report was compiled from calciner operating data, waste solution analyses and volumes calcined, calciner operating schedules, calcine temperature monitoring records, and facility design of the calcined solids storage facilities. A compact disk copy of this report is provided to facilitate future data manipulations and analysis.
Date: January 1, 2005
Creator: Staiger, Merle Daniel & Swenson, M. C.
Object Type: Report
System: The UNT Digital Library
Carbon Dioxide Capture From Flue Gas Using Dry Regenerable Sorbents Quarterly Technical Progress Report: October-December 2004 (open access)

Carbon Dioxide Capture From Flue Gas Using Dry Regenerable Sorbents Quarterly Technical Progress Report: October-December 2004

This report describes research conducted between October 1, 2004 and December 31, 2004 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. Two supported sorbents were tested in a bench scale fluidized bed reactor system. The sorbents were prepared by impregnation of sodium carbonate on to an inert support at a commercial catalyst manufacturing facility. One sorbent, tested through five cycles of carbon dioxide sorption in an atmosphere of 3% water vapor and 0.8 to 3% carbon dioxide showed consistent reactivity with sodium carbonate utilization of 7 to 14%. A second, similarly prepared material, showed comparable reactivity in one cycle of testing. Batches of 5 other materials were prepared in laboratory scale quantities (primarily by spray drying). These materials generally have significantly greater surface areas than calcined sodium bicarbonate. Small scale testing showed no significant adsorption of mercury on representative carbon dioxide sorbent materials under expected flue gas conditions.
Date: January 1, 2005
Creator: Green, David A.; Turk, Brian S.; Portzer, Jeffrey W.; Nelson, Thomas & Gupta, Raghubir P.
Object Type: Report
System: The UNT Digital Library
Carbon Dioxide Flux Measurement Systems (CO2Flux) Handbook (open access)

Carbon Dioxide Flux Measurement Systems (CO2Flux) Handbook

The Southern Great Plains (SGP) carbon dioxide flux (CO2 flux) measurement systems provide half-hour average fluxes of CO2, H2O (latent heat), and sensible heat. The fluxes are obtained by the eddy covariance technique, which computes the flux as the mean product of the vertical wind component with CO2 and H2O densities, or estimated virtual temperature. A three-dimensional sonic anemometer is used to obtain the orthogonal wind components and the virtual (sonic) temperature. An infrared gas analyzer is used to obtain the CO2 and H2O densities. A separate sub-system also collects half-hour average measures of meteorological and soil variables from separate 4-m towers.
Date: January 1, 2005
Creator: Fischer, M
Object Type: Report
System: The UNT Digital Library
Carbon Sequestration in Reclaimed Mined Soils of Ohio (open access)

Carbon Sequestration in Reclaimed Mined Soils of Ohio

Assessment of soil organic carbon (SOC) sequestration potential of reclaimed minesoils (RMS) is important for preserving environmental quality and increasing agronomic yields. The experimental sites were characterized by distinct age chronosequences of reclaimed minesoil and were located in Guernsey, Morgan, Noble, and Muskingum Counties of Ohio. These sites are owned and maintained by Americal Electrical Power. These sites were reclaimed (1) with topsoil application, and (2) without topsoil application, and were under continuous grass or forest cover. In this report results are presented from the sites reclaimed without topsoil application between 1956 and 1969. Three sites are under continuous grass cover and the three under forest cover since reclamation. Three core and three bulk soil samples were collected from each site from three slope positions (upper; middle, and lower) for 0-15 cm and 15-30 cm depths, and texture, pH and electrical conductivity (EC), soil bulk density ({rho}{sub b}), SOC, total nitrogen (TN) stocks were determined. No differences in sand and clay contents, bulk density, SOC and TN stocks were observed within different slope positions within each site. However, sand [R56-G (17.1%) < R69-G (29.1%) = R62-G (29.1%)], and silt [R56-G (58.3%) > R69-G (47.7%)] contents, bulk density [R62-G (1.25 Mg …
Date: January 1, 2005
Creator: Shukla, M.K. & Lal, R.
Object Type: Report
System: The UNT Digital Library
Causes and prevention of symptom complaints in office buildings:Distilling the experience of indoor environmental qualityinvestigators (open access)

Causes and prevention of symptom complaints in office buildings:Distilling the experience of indoor environmental qualityinvestigators

The goal of this project was to develop empirically based recommendations for practical strategies, suitable for use by those who own, lease, or manage office space, to prevent building-related symptoms in office buildings. Ideas from six experienced building investigators were gathered and prioritized in a multi-day workshop. The top ranked problems identified were, in priority order: excessive building moisture, inadequate outdoor air, dust on indoor surfaces, indoor gases and odors, inadequate thermal control, and inadequate attention by management to indoor environments. The highest priority strategies recommended for preventing building-related symptoms were: managing water at building exteriors, operating ventilation systems per design intent, providing at least minimum ventilation rates, and maintaining indoor temperatures at 72 F {+-} 2{sup o}. Findings in the scientific literature were generally consistent with these recommendations. IEQ investigators showed considerable agreement on the most important causes of symptom complaints in office buildings and the key methods for preventing these problems. Despite the range of climates in which they worked, the investigators agreed that the highest priority prevention strategy was managing water at building exteriors. These recommendations, generally consistent with available research findings, provide useful practical guidelines for those who own, manage or maintain office buildings. The empirical …
Date: January 1, 2005
Creator: Mendell, Mark J.; Diamond, Richard C.; Fisk, William J.; Brennan,Terry; Hathon, Lee; Odom, J. David et al.
Object Type: Article
System: The UNT Digital Library
CERAMIC MEMBRANE ENABLING TECHNOLOGY FOR IMPROVED IGCC EFFICIENCY (open access)

CERAMIC MEMBRANE ENABLING TECHNOLOGY FOR IMPROVED IGCC EFFICIENCY

This quarterly technical progress report will summarize work accomplished for Phase 2 Program during the quarter April to June 2004. In task 7, reactor cost analysis was performed to determine whether OTM technology when integrated with IGCC provides a commercially attractive process. In task 9, discussions with DOE regarding restructuring the program continued. The objectives of the second year of phase 2 of the program are to construct and operate an engineering pilot reactor for OTM oxygen. Work to support this objective is being undertaken in the following areas in this quarter: IGCC process analysis and economics.
Date: January 1, 2005
Creator: Sirman, John
Object Type: Report
System: The UNT Digital Library
Characterization of Photovoltaic Concentrators (open access)

Characterization of Photovoltaic Concentrators

This paper will describe the resources at the National Renewable Energy Laboratory (NREL) for performing characterization of photovoltaic (PV) materials designed for operation under concentrated light. NREL has the capability to measure devices ranging from very small, unencapsulated research cells to reasonably sized, environmentally protected modules. Data gathering and interpretation are also ongoing areas of revision and improvement. The main goal of the current research is to reduce the measurement uncertainty to the lowest practical value. At present, the state of the art is limited at a ?5% level in measuring efficiency accurately.
Date: January 1, 2005
Creator: Kiehl, J. & Emery, E.
Object Type: Article
System: The UNT Digital Library
Characterizing the effects of scale and heating rate on micro-scale explosive ignition criteria. (open access)

Characterizing the effects of scale and heating rate on micro-scale explosive ignition criteria.

Laser diode ignition experiments were conducted in an effort to characterize the effects of scale and heating rate on micro-scale explosive ignition criteria. Over forty experiments were conducted with various laser power densities and laser spot sizes. In addition, relatively simple analytical and numerical calculations were performed to assist with interpretation of the experimental data and characterization of the explosive ignition criteria.
Date: January 1, 2005
Creator: Hafenrichter, Everett Shingo & Pahl, Robert J.
Object Type: Report
System: The UNT Digital Library
Charm and beauty production at CDF (open access)

Charm and beauty production at CDF

Using the data samples collected with the CDF Run II detector during 2002 and early 2003, new measurements of the production cross sections of charm and beauty hadrons at {radical}s = 1960 GeV are presented. New measurements of the cross sections of centrally produced b-hadrons and J/{psi} mesons down to zero transverse momenta have been carried out. The large charm signals made available by the silicon vertex track trigger have enabled the measurement of the cross sections of D{sup 0}, D*, D{sup {+-}}, and D{sub s} mesons.
Date: January 1, 2005
Creator: Bishai, M.
Object Type: Article
System: The UNT Digital Library
Chilled Mirror Dew Point Hygrometer (CM) Handbook (open access)

Chilled Mirror Dew Point Hygrometer (CM) Handbook

The CM systems have been developed for the ARM Program to act as a moisture standard traceable to National Institute of Standards and Technology (NIST). There are three CM systems that are each fully portable, self-contained, and require only 110 V AC power. The systems include a CM sensor, air sampling and filtration system, a secondary reference (Rotronic HP043 temperature and relative humidity sensor) to detect system malfunctions, a data acquisition system, and data storage for more than one month of 1-minute data. The CM sensor directly measures dew point temperature at 1 m, air temperature at 2 m, and relative humidity at 2 m. These measurements are intended to represent self-standing data streams that can be used independently or in combinations.
Date: January 1, 2005
Creator: Ritsche, MT
Object Type: Report
System: The UNT Digital Library
CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and Accomplishments (open access)

CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and Accomplishments

This short paper is a summary of our investigations in three major areas: high-efficiency CuInGaSe2 (CIGS) solar cells, junctions made using chemical bath deposited ZnS(O,OH) buffer layers, and solar cells fabricated from thinner absorbers. Significant progress was made in all areas. We describe how our research has contributed to the fundamental understanding and the practical application of CIGS materials to high performance solar cells.
Date: January 1, 2005
Creator: Ramanathan, K.; Bhattacharya, R. N.; Contreras, M. A.; Hasoon, F. S.; Abushama, J. & Noufi, R.
Object Type: Article
System: The UNT Digital Library