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Texas Attorney General Opinion: GA-0175 (open access)

Texas Attorney General Opinion: GA-0175

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification; Consequences for a municipality if five of it's seven council members are removed at a recall election (RQ-0156-GA)
Date: April 6, 2004
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Measurement of the polarization of the K-shell resonance line emission of S13+ and S14+ at relativistic electron beam energies. (open access)

Measurement of the polarization of the K-shell resonance line emission of S13+ and S14+ at relativistic electron beam energies.

We have measured the polarization of the heliumlike sulfur resonance line 1s2p {sup 1}P{sub 1} {yields} 1s{sup 2} {sup 1}S{sub 0}, and of the blend of the lithiumlike sulfur resonance lines 1s2s2p {sup 2}P{sub 3/2} {yields} 1s{sup 2}2s {sup 2}S{sub 1/2} and 1s2s2p {sup 2}P{sub 1/2} {yields} 1s{sup 2}2s {sup 2}S{sub 1/2} as a function of electron beam energy from near threshold to 144 keV. These lines were excited with the LLNL high-energy electron beam ion trap and measured using a newly modified two-crystal technique. Our results test polarization predictions in an energy regime where few empirical results have been reported. We also present calculations of the polarization using two different methods, and good agreement is obtained.
Date: April 6, 2004
Creator: Robbins, D; Faenov, A Y; Pikuz, T; Chen, H; Beiersdorfer, P; May, M et al.
Object Type: Article
System: The UNT Digital Library
The DNA sequence and biology of human chromosome 19 (open access)

The DNA sequence and biology of human chromosome 19

Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high GC content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in Mendelian disorders, including familial hypercholesterolemia and insulin-resistant diabetes. Nearly one quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.
Date: April 6, 2004
Creator: Grimwood, J.; Gordon, L. A.; Olsen, A.; Terry, A.; Schmutz, J.; Lamerdin, J. et al.
Object Type: Article
System: The UNT Digital Library
Carbon Nanotube-Based Permeable Membranes (open access)

Carbon Nanotube-Based Permeable Membranes

A membrane of multiwalled carbon nanotubes embedded in a silicon nitride matrix was fabricated for use in studying fluid mechanics on the nanometer scale. Characterization by fluorescent tracer diffusion and scanning electron microscopy suggests that the membrane is void-free near the silicon substrate on which it rests, implying that the hollow core of the nanotube is the only conduction path for molecular transport. Assuming Knudsen diffusion through this nanotube membrane, a maximum helium transport rate (for a pressure drop of 1 atm) of 0.25 cc/sec is predicted. Helium flow measurements of a nanoporous silicon nitride membrane, fabricated by sacrificial removal of carbon, give a flow rate greater than 1x10{sup -6} cc/sec. For viscous, laminar flow conditions, water is estimated to flow across the nanotube membrane (under a 1 atm pressure drop) at up to 2.8x10{sup -5} cc/sec (1.7 {micro}L/min).
Date: April 6, 2004
Creator: Holt, J K; Park, H G; Bakajin, O; Noy, A; Huser, T & Eaglesham, D
Object Type: Article
System: The UNT Digital Library
Simulation of Ventilation Efficiency, Temperatures, and Relative Humidities in Emplacement Drifts at Yucca Mountain, Nevada, Using Monte Carlo and Composite Thermal-Pulse Methods (open access)

Simulation of Ventilation Efficiency, Temperatures, and Relative Humidities in Emplacement Drifts at Yucca Mountain, Nevada, Using Monte Carlo and Composite Thermal-Pulse Methods

Predictions of waste canister and repository driftwall temperatures as a function of space and time are of fundamental importance to evaluating pre-closure and post-closure design requirements and performance assessment of the proposed repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. Variations in the lithostratigraphic features in densely welded and crystallized rocks of the 12.8-million-year-old Topopah Spring Tuff, especially the porosity resulting from lithophysal cavities, are projected 50 to 800 m from the Enhanced Characterization of the Repository Block cross drift to a simulated ''Panel 1'' emplacement drift. Lithophysal cavity porosity varies from 0.00 to 0.05 cm{sup 3}/cm{sup 3} in the middle nonlithophysal zone and from 0.03 to 0.28 cm{sup 3}/cm{sup 3} in the lower lithophysal zone. Many thermal properties are related to lithophysal cavity porosity, and computer code titled ''Monte Carlo Simulation of Ventilation'' (MCSIMVENT) has been developed for simulating statistical variability and uncertainty along the simulated emplacement drift. The MCSIMVENT code, which is based on a composite thermal-pulse calculation, is used to calculate pre-closure ventilation efficiency and peak post-closure temperatures and relative humidities along the simulated emplacement drift for as much as 1,000 years. Variations in lithophysal porosity along the drift can result in …
Date: April 6, 2004
Creator: Case, J. & Buesch, D.
Object Type: Report
System: The UNT Digital Library
Creation of an antiferromagnetic exchange spring (open access)

Creation of an antiferromagnetic exchange spring

We present evidence for the creation of an exchange spring in an antiferromagnet due to exchange coupling to a ferromagnet. X-ray magnetic linear dichroism spectroscopy on single crystal Co/NiO(001) shows that a partial domain wall is wound up at the surface of the antiferromagnet when the adjacent ferromagnet is rotated by a magnetic field. We determine the interface exchange stiffness and the antiferromagnetic domain wall energy from the field dependence of the direction of the antiferromagnetic axis, the antiferromagnetic pendant to a ferromagnetic hysteresis loop. The existence of a planar antiferromagnetic domain wall, proven by our measurement, is a key assumption of most exchange bias models.
Date: April 6, 2004
Creator: Scholl, A.; Liberati, M.; Arenholz, E.; Ohldag, H. & Stohr, J.
Object Type: Article
System: The UNT Digital Library
POST WATERFLOOD CO2 MISCIBLE FLOOD IN LIGHT OIL FLUVIAL DOMINATED DELTAIC RESERVOIR (open access)

POST WATERFLOOD CO2 MISCIBLE FLOOD IN LIGHT OIL FLUVIAL DOMINATED DELTAIC RESERVOIR

Texaco Exploration and Production Inc. (TEPI) and the US Department of Energy (DOE) entered into a cost sharing cooperative agreement to conduct an Enhanced Oil Recovery demonstration project at Port Neches. The field is located in Orange County near Beaumont, Texas, and shown in Appendix A. The project would demonstrate the effectiveness of the CO{sub 2} miscible process in Fluvial Dominated Deltaic reservoirs. It would also evaluate the use of horizontal CO{sub 2} injection wells to improve the overall sweep efficiency and determine the recovery efficiency of CO{sub 2} floods in waterflooded and partial waterdrive reservoirs. Texaco's objective on this project was (1) to utilize all available technologies, and to develop new ones, and (2) to design a CO{sub 2} flood process which is cost effective and can be applied to many other reservoirs throughout the US. A database of potential reservoirs for the gulf coast region was developed by LSU, using a screening model developed by Texaco Research Center in Houston. A PC-based CO{sub 2} screening model was developed and the aforementioned database generated to show the utility of this technology throughout the US. Finally, the results and the information gained from this project was disseminated throughout the oil …
Date: April 6, 2004
Creator: Tipton, Tim
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 127, Ed. 1 Tuesday, April 6, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 127, Ed. 1 Tuesday, April 6, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: April 6, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 88, No. 100, Ed. 1 Tuesday, April 6, 2004 (open access)

North Texas Daily (Denton, Tex.), Vol. 88, No. 100, Ed. 1 Tuesday, April 6, 2004

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: April 6, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Education for the Disadvantaged: Overview of ESEA Title I-A Amendments Under the No Child Left Behind Act (open access)

Education for the Disadvantaged: Overview of ESEA Title I-A Amendments Under the No Child Left Behind Act

This report provides an overview of aspects of Elementary and Secondary Education Act (ESEA) Title I-A which were substantially amended by the No Child Left Behind Act of 2001 (NCLBA); elements of the program which are important but which were not substantially revised by the NCLBA (such as parental involvement requirements) are not discussed in this report.
Date: April 6, 2004
Creator: Riddle, Wayne
Object Type: Report
System: The UNT Digital Library
Visa Waiver Program (open access)

Visa Waiver Program

None
Date: April 6, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Quantifying the effects of limited CO2 fertilization on future climate (open access)

Quantifying the effects of limited CO2 fertilization on future climate

The response of the land biosphere to the ongoing increase in atmospheric CO{sub 2} is not fully understood. To evaluate the approximate upper and lower limits of land sequestration of carbon, we performed simulations using a comprehensive carbon-climate model. In one case the land biosphere is vigorously fertilized by added CO{sub 2} and sequesters carbon throughout the 21st century. In a second case, CO{sub 2} fertilization saturates in year 2000; in this case the land becomes an additional source of CO{sub 2} by 2050. The predicted atmospheric CO{sub 2} concentration at year 2100 differs by 40% between the two cases. Current uncertainties preclude determination of whether the land biosphere will amplify or damp atmospheric CO{sub 2} increases by the end of the century.
Date: April 6, 2004
Creator: Erickson, D.; Govindasamy, B.; Caldeira, K.; Mirin, A.; Thompson, S. L.; Delire, C. et al.
Object Type: Report
System: The UNT Digital Library
Segregation of Tungsten to Interfaces in Lamellar TiAl (open access)

Segregation of Tungsten to Interfaces in Lamellar TiAl

None
Date: April 6, 2004
Creator: Hsiung, L L & Briant, C L
Object Type: Report
System: The UNT Digital Library
Resolving Nuclear Reactor Lifetime Extension Questions: A Combined Multiscale Modeling and Positron Characterization approach (open access)

Resolving Nuclear Reactor Lifetime Extension Questions: A Combined Multiscale Modeling and Positron Characterization approach

The objective of this work is to determine the chemical composition of nanometer precipitates responsible for irradiation hardening and embrittlement of reactor pressure vessel steels, which threaten to limit the operating lifetime of nuclear power plants worldwide. The scientific approach incorporates computational multiscale modeling of radiation damage and microstructural evolution in Fe-Cu-Ni-Mn alloys, and experimental characterization by positron annihilation spectroscopy and small angle neutron scattering. The modeling and experimental results are
Date: April 6, 2004
Creator: Wirth, B.; Asoka-Kumar, P.; Denison, A.; Glade, S.; Howell, R.; Marian, J. et al.
Object Type: Report
System: The UNT Digital Library
Human UDP-Glucuronosyltransferase 1A1 is the Primary Enzyme Responsible for the N-glucuronidation of N-hydroxy-PhIP in vitro (open access)

Human UDP-Glucuronosyltransferase 1A1 is the Primary Enzyme Responsible for the N-glucuronidation of N-hydroxy-PhIP in vitro

UDP-Glucuronosyltransferase 1A proteins (UGT1A) catalyze the glucuronidation of many endogenous and xenobiotic compounds including heterocyclic amines and their hydroxylated metabolites (the main topic of this study). Studies have shown that in humans UGT1A mediated glucuronidation is an important pathway in the detoxification of food-borne carcinogenic heterocyclic amines. The biotransformation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), the most mass abundant heterocyclic amine found in cooked meats, is highly dependent on cytochrome P4501A2 hydroxylation followed by UGT catalyzed glucuronidation of the N-hydroxy-PhIP reactive intermediate. To determine which UGT1A proteins are involved in the glucuronidation of N-hydroxy-PhIP, microsomal preparations from baculovirus infected insect cells that express all of the known functional human UGT1A isozymes (UGT1A1, -1A3, -1A4, -1A6, -1A7, -1A8, -1A9, -1A10) were exposed to N-hydroxy-PhIP and the reaction products were isolated by HPLC. All UGT1A proteins except UGT1A6 showed some degree of activity towards N-hydroxy-PhIP. The formation of both N-hydroxy-PhIP-N{sup 2}-glucuronide and N-hydroxy-PhIP-N3-glucuronide was both time and substrate concentration dependent in all the microsomal incubations that showed appreciable activity. UGT1A1 was the most efficient in converting N-hydroxy-PhIP to both conjugates producing 5 times more of the N{sup 2}-conjugate than UGT1A4, the next active UGT, and 286 times more than UGT1A7, the least active UGT. With …
Date: April 6, 2004
Creator: Malfatti, M A & Felton, J S
Object Type: Article
System: The UNT Digital Library
Unique Gold Nanoparticle Aggregates as a Highly Active SERS Substrate (open access)

Unique Gold Nanoparticle Aggregates as a Highly Active SERS Substrate

A unique gold nanoparticle aggregate (GNA) system has been shown to be an excellent substrate for surface-enhanced Raman scattering (SERS) applications. Rhodamine 6G (R6G), a common molecule used for testing SERS activity on silver, but generally difficult to detect on gold substrates, has been found to readily bind to the GNA and exhibit strong SERS activity due to the unique surface chemistry afforded by sulfur species on the surface. This GNA system has yielded a large SERS enhancement of 10{sup 7}-10{sup 9} in bulk solution for R6G, on par with or greater than any previously reported gold SERS substrate. SERS activity has also been successfully demonstrated for several biological molecules including adenine, L-cysteine, L-lysine, and L-histidine for the first time on a gold SERS substrate, showing the potential of this GNA as a convenient and powerful SERS substrate for biomolecular detection. In addition, SERS spectrum of R6G on single aggregates has been measured. We have shown that the special surface properties of the GNA, in conjunction with strong near IR absorption, make it useful for SERS analysis of a wide variety of molecules.
Date: April 6, 2004
Creator: Schwartzberg, A M; Grant, C D; Wolcott, A; Talley, C E; Huser, T R; Bogomolni, R et al.
Object Type: Article
System: The UNT Digital Library
Tobacco Quota Buyout Proposals in the 108th Congress (open access)

Tobacco Quota Buyout Proposals in the 108th Congress

None
Date: April 6, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library

Ensemble: 2004-04-06 – Lab Band Madness

Access: Use of this item is restricted to the UNT Community
Concert performed at UNT Murchison Performing Arts Center, Winspear Hall on April 6, 2004.
Date: April 6, 2004
Creator: Beckett, Jonathan; Brunkhorst, Kevin; Cloninger, Jesse; Edwards, Ken; Riggs, James; Saunders, Jay et al.
Object Type: Sound
System: The UNT Digital Library
A 1-Joule laser for a 16-fiber injection system (open access)

A 1-Joule laser for a 16-fiber injection system

A 1-J laser was designed to launch light down 16, multi-mode fibers (400-{micro}m-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation (DOC), and was delivered by DOC. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no ''hot spots,'' a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by system efficiency where a pristine TEM{sub 00} laser beam would be required. The laser is a master oscillator, power amplifier (MOPA) consisting of a 4-mm-dia. Nd:YLF rod in the stable, q-switched oscillator and a 9.5-mm-dia. Nd:YLF rod in the double-passed amplifier. Using a TEM{sub 00} oscillator beam resulted in excellent transmission efficiencies through the fibers at lower energies but proved to be quite unreliable at higher energies, causing premature fiber damage, flyer plate rupture, stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Upon further investigation, it was found that both temporal and spatial beam formatting of the laser were required to successfully initiate the PETN. Results from the single-mode experiments, including fiber damage, SRS and SBS losses, will be presented. In …
Date: April 6, 2004
Creator: Honig, J.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 5, Ed. 1 Tuesday, April 6, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 5, Ed. 1 Tuesday, April 6, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 6, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Rains County Leader (Emory, Tex.), Vol. 116, No. 42, Ed. 1 Tuesday, April 6, 2004 (open access)

Rains County Leader (Emory, Tex.), Vol. 116, No. 42, Ed. 1 Tuesday, April 6, 2004

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: April 6, 2004
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Development of Design Criteria for Fluid Induced Structural Vibrations in Steam Generators and Heat Exchangers (open access)

Development of Design Criteria for Fluid Induced Structural Vibrations in Steam Generators and Heat Exchangers

Flow-induced vibration in heat exchangers has been a major cause of concern in the nuclear industry for several decades. Many incidents of failure of heat exchangers due to apparent flow-induced vibration have been reported through the USNRC incident reporting system. Almost all heat exchangers have to deal with this problem during their operation. The phenomenon has been studied since the 1970s and the database of experimental studies on flow-induced vibration is constantly updated with new findings and improved design criteria for heat exchangers.
Date: April 6, 2004
Creator: Catton, Uvan; Dhir, Vijay K.; Mitra, Deepanjan; Alquaddoomi, Omar & Adinolfi, Pierangelo
Object Type: Report
System: The UNT Digital Library
The D0 online monitoring and automatic DAQ recovery (open access)

The D0 online monitoring and automatic DAQ recovery

The DZERO experiment, located at the Fermi National Accelerator Laboratory, has recently started the Run 2 physics program. The detector upgrade included a new Data Acquisition/Level 3 Trigger system. Part of the design for the DAQ/Trigger system was a new monitoring infrastructure. The monitoring was designed to satisfy real-time requirements with 1-second resolution as well as nonreal-time data. It was also designed to handle a large number of displays without putting undue load on the sources of monitoring information. The resulting protocol is based on XML, is easily extensible, and has spawned a large number of displays, clients, and other applications. It is also one of the few sources of detector performance available outside the Online System's security wall. A tool, based on this system, which provides for auto-recovery of DAQ errors, has been designed. This talk will include a description of the DZERO DAQ/Online monitor server, based on the ACE framework, the protocol, the auto-recovery tool, and several of the unique displays which include an ORACLE-based archiver and numerous GUIs.
Date: April 6, 2004
Creator: al., A. Haas et
Object Type: Article
System: The UNT Digital Library
CO2 splitting by H2O to CO and O2 under UV light in TiMCM-41silicate sieve (open access)

CO2 splitting by H2O to CO and O2 under UV light in TiMCM-41silicate sieve

The 266 nm light-induced reaction of CO{sub 2} and H{sub 2}O gas mixtures (including isotopic modifications {sup 13}CO{sub 2}, C{sup 18}O{sub 2}, and D{sub 2}O) in framework TiMCM-41 silicate sieve was monitored by in-situ FT-IR spectroscopy at room temperature. Carbon monoxide gas was observed as the sole product by infrared, and the growth was found to depend linearly on the photolysis laser power. H{sub 2}O was confirmed as stoichiometric electron donor. The work establishes CO as the single photon, 2-electron transfer product of CO{sub 2} photoreduction by H{sub 2}O at framework Ti centers for the first time. O{sub 2} was detected as co-product by mass spectrometric analysis of the photolysis gas mixture. These results are explained by single UV photon-induced splitting of CO{sub 2} by H{sub 2}O to CO and surface OH radical.
Date: April 6, 2004
Creator: Lin, Wenyong; Han, Hongxian & Frei, Heinz
Object Type: Article
System: The UNT Digital Library