New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography (open access)

New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography

This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.
Date: December 19, 2008
Creator: Doster, J. Michael
Object Type: Report
System: The UNT Digital Library
New York Nano-Bio Molecular Information Technology (NYNBIT) Incubator (open access)

New York Nano-Bio Molecular Information Technology (NYNBIT) Incubator

This project presents the outcome of an effort made by a consortium of six universities in the State of New York to develop a Center for Advanced technology (CAT) in the emerging field of Nano-Bio-Molecular Information Technology. The effort consists of activities such as organization of the NYNBIT incubator, collaborative research projects, development of courses, an educational program for high schools, and commercial start-up programs.
Date: December 19, 2008
Creator: Das, Digendra K
Object Type: Report
System: The UNT Digital Library
Seismic Survey Report for Central Nevada Test Area, Subsurface, Correction Action Unit 443, Revision 1 (open access)

Seismic Survey Report for Central Nevada Test Area, Subsurface, Correction Action Unit 443, Revision 1

The seismic survey was successful in imaging the water table and underlying structures at the site. The configuration of the water table reflector confirms the general southeast horizontal flow direction in the alluvial aquifer. Offsets in the water table reflector, both at known faults that reach the surface and at subsurface faults not previously recognized, indicate that both extension and blast-related faults are barriers to lateral groundwater flow. The results from this study have been used to optimally locate two new wells designed to monitor head levels and possible contaminant migration in the alluvial aquifer at CTNA.
Date: December 19, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Automated Demand Response Opportunities in Wastewater Treatment Facilities (open access)

Automated Demand Response Opportunities in Wastewater Treatment Facilities

Wastewater treatment is an energy intensive process which, together with water treatment, comprises about three percent of U.S. annual energy use. Yet, since wastewater treatment facilities are often peripheral to major electricity-using industries, they are frequently an overlooked area for automated demand response opportunities. Demand response is a set of actions taken to reduce electric loads when contingencies, such as emergencies or congestion, occur that threaten supply-demand balance, and/or market conditions occur that raise electric supply costs. Demand response programs are designed to improve the reliability of the electric grid and to lower the use of electricity during peak times to reduce the total system costs. Open automated demand response is a set of continuous, open communication signals and systems provided over the Internet to allow facilities to automate their demand response activities without the need for manual actions. Automated demand response strategies can be implemented as an enhanced use of upgraded equipment and facility control strategies installed as energy efficiency measures. Conversely, installation of controls to support automated demand response may result in improved energy efficiency through real-time access to operational data. This paper argues that the implementation of energy efficiency opportunities in wastewater treatment facilities creates a base …
Date: November 19, 2008
Creator: Thompson, Lisa; Song, Katherine; Lekov, Alex & McKane, Aimee
Object Type: Article
System: The UNT Digital Library
Collaborative Systemwide Monitoring and Evaluation Project (CSMEP) - Year 5 : Annual Report for FY 2008. (open access)

Collaborative Systemwide Monitoring and Evaluation Project (CSMEP) - Year 5 : Annual Report for FY 2008.

The Collaborative Systemwide Monitoring and Evaluation Project (CSMEP) is a coordinated effort to improve the quality, consistency, and focus of fish population and habitat data to answer key monitoring and evaluation questions relevant to major decisions in the Columbia River Basin. CSMEP was initiated by the Columbia Basin Fish and Wildlife Authority (CBFWA) in October 2003. The project is funded by the Bonneville Power Administration (BPA) through the Northwest Power and Conservation Council's Fish and Wildlife Program (NPCC). CSMEP is a major effort of the federal state and Tribal fish and wildlife managers to develop regionally integrated monitoring and evaluation (M&E) across the Columbia River Basin. CSMEP has focused its work on five monitoring domains: status and trends monitoring of populations and action effectiveness monitoring of habitat, harvest, hatcheries, and the hydrosystem. CSMEP's specific goals are to: (1) interact with federal, state and tribal programmatic and technical entities responsible for M&E of fish and wildlife, to ensure that work plans developed and executed under this project are well integrated with ongoing work by these entities; (2) document, integrate, and make available existing monitoring data on listed salmon, steelhead, bull trout and other fish species of concern; (3) critically assess strengths …
Date: November 19, 2008
Creator: Marmorek, David R.; Porter, Marc; Pickard, Darcy & Wieckowski, Katherine
Object Type: Report
System: The UNT Digital Library
Final Work Plan: Investigation of Potential Contamination at the Former CCC/Usda Grain Storage Facility in Hanover, Kansas. (open access)

Final Work Plan: Investigation of Potential Contamination at the Former CCC/Usda Grain Storage Facility in Hanover, Kansas.

The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility at the northeastern edge of the city of Hanover, Kansas, from 1950 until the early 1970s. During this time, commercial grain fumigants containing carbon tetrachloride were in common use by the grain storage industry to preserve grain in their facilities. In February 1998, trace to low levels of carbon tetrachloride (below the maximum contaminant level [MCL] of 5.0 {micro}g/L) were detected in two private wells near the former grain storage facility at Hanover, as part of a statewide USDA private well sampling program that was implemented by the Kansas Department of Health and Environment (KDHE) near former CCC/USDA facilities. In April 2007, the CCC/USDA collected near-surface soil samples at 1.8-2 ft BGL (below ground level) at 61 locations across the former CCC/USDA facility. All soil samples were analyzed by the rigorous gas chromatograph-mass spectrometer analytical method (purge-and-trap method). No contamination was found in soil samples above the reporting limit of 10 {micro}g/kg. In July 2007, the CCC/USDA sampled indoor air at nine residences on or adjacent to its former facility to address the residents concerns regarding vapor intrusion. Low levels of …
Date: November 19, 2008
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Load Reduction, Demand Response and Energy Efficient Technologies and Strategies (open access)

Load Reduction, Demand Response and Energy Efficient Technologies and Strategies

The Department of Energy’s (DOE’s) Pacific Northwest National Laboratory (PNNL) was tasked by the DOE Office of Electricity (OE) to recommend load reduction and grid integration strategies, and identify additional demand response (energy efficiency/conservation opportunities) and strategies at the Forest City Housing (FCH) redevelopment at Pearl Harbor and the Marine Corps Base Hawaii (MCBH) at Kaneohe Bay. The goal was to provide FCH staff a path forward to manage their electricity load and thus reduce costs at these FCH family housing developments. The initial focus of the work was at the MCBH given the MCBH has a demand-ratchet tariff, relatively high demand (~18 MW) and a commensurate high blended electricity rate (26 cents/kWh). The peak demand for MCBH occurs in July-August. And, on average, family housing at MCBH contributes ~36% to the MCBH total energy consumption. Thus, a significant load reduction in family housing can have a considerable impact on the overall site load. Based on a site visit to the MCBH and meetings with MCBH installation, FCH, and Hawaiian Electric Company (HECO) staff, recommended actions (including a "smart grid" recommendation) that can be undertaken by FCH to manage and reduce peak-demand in family housing are made. Recommendations are also …
Date: November 19, 2008
Creator: Boyd, Paul A.; Parker, Graham B. & Hatley, Darrel D.
Object Type: Report
System: The UNT Digital Library
NSTX: Facility/Research Highlights and Near Term Facility Plans (open access)

NSTX: Facility/Research Highlights and Near Term Facility Plans

The National Spherical Torus Experiment (NSTX) is a collaborative mega-ampere-class spherical torus research facility with high power heating and current drive systems and the state-of-the-art comprehensive diagnostics. For the 2008 experimental campaign, the high harmonic fast wave (HHFW) heating efficiency in deuterium improved significantly with lithium evaporation and produced a record central Te of 5 keV. The HHFW heating of NBI-heated discharges was also demonstrated for the first time with lithium application. The EBW emission in H-mode was also improved dramatically with lithium which was shown to be attributable to reduced edge collisional absorption. Newly installed FIDA energetic particle diagnostic measured significant transport of energetic ions associated with TAE avalanche as well as n=1 kink activities. A full 75 channel poloidal CHERS system is now operational yielding tantalizing initial results. In the near term, major upgrade activities include a liquid-lithium divertor target to achieve lower collisionality regime, the HHFW antenna upgrades to double its power handling capability in H-mode, and a beam-emission spectroscopy diagnostic to extend the localized turbulence measurements toward the ion gyro-radius scale from the present concentration on the electron gyro-radius scale. For the longer term, a new center stack to significantly expand the plasma operating parameters is …
Date: November 19, 2008
Creator: Ono, M.
Object Type: Article
System: The UNT Digital Library
RESULTS OF TRITIUM TRACKING AND GROUNDWATER MONITORING AT THE HANFORD SITE 200 AREA STATE APPROVED LAND DISPOSAL SITE FY2008 (open access)

RESULTS OF TRITIUM TRACKING AND GROUNDWATER MONITORING AT THE HANFORD SITE 200 AREA STATE APPROVED LAND DISPOSAL SITE FY2008

The Hanford Site's 200 Area Effluent Treatment Facility (ETF) processes contaminated aqueous wastes derived from Hanford Site facilities. The treated wastewater occasionally contains tritium, which cannot be removed by the ETF prior to the wastewater being discharged to the 200 Area State-Approved Land Disposal Site (SALDS). During the first 11 months of fiscal year 2008 (FY08) (September 1, 2007, to July 31, 2008), approximately 75.15 million L (19.85 million gal) of water were discharged to the SALDS. Groundwater monitoring for tritium and other constituents, as well as water-level measurements, is required for the SALDS by State Waste Discharge Permit Number ST-4500 (Ecology 2000). The current monitoring network consists of three proximal (compliance) monitoring wells and nine tritium-tracking wells. Quarterly sampling of the proximal wells occurred in October 2007 and in January/February 2008, April 2008, and August 2008. The nine tritium-tracking wells, including groundwater monitoring wells located upgradient and downgradient of the SALDS, were sampled in January through April 2008. Water-level measurements taken in the three proximal SALDS wells indicate that a small groundwater mound is present beneath the facility, which is a result of operational discharges. The mound increased in FY08 due to increased ETF discharges from treating groundwater from …
Date: November 19, 2008
Creator: DB, ERB
Object Type: Report
System: The UNT Digital Library
(Cd,Mn)Te detectors for characterization of x-ray emissions generated during laser-driven fusion experiments (open access)

(Cd,Mn)Te detectors for characterization of x-ray emissions generated during laser-driven fusion experiments

We present our measurements of (Cd,Mn)Te photoconductive detectors (PCDs), fabricated for the goal of measuring both the temporal and spectral dependences of X-ray emissions generated from laser-illuminated targets during the inertial confinement fusion experiments. Our Cd{sub 1-x}Mn{sub x}Te (x = 0.05) single crystals, doped with V, were grown using a vertical Bridgman method and, subsequently, annealed in Cd for the highest resistivity ({approx}10{sup 10} {Omega}cm) and a good mobility-lifetime product ({approx}10{sup -3} cm{sup 2}/V). The 1-mm- and 2.3-mm-thick detectors were placed in the same housing as two 1-mm-thick diamond PCDs. All devices were pre-screened by a 7.6-mm-thick Be X-ray filter with a frequency cutoff of 1 keV. The incident shots from the OMEGA laser were 1-ns-long square pulses with energies ranging from 2.3 kJ to 22.6 kJ, and the PCDs were biased with 5000 V/cm. The response amplitudes and rise times of our (Cd,Mn)Te PCDs were comparable with the diamond detector performance, while the decay times were 4 to 10 times longer and in the 2-5 ns range. We observed two X-ray emission events separated by 1.24 ns. The first was identified as caused by heating of the target and creating a hot corona, while the second one was from …
Date: October 19, 2008
Creator: Cross, A. S.; Knauer, J. P.; Mycielski, A.; Kochanowska, D.; Wiktowska-Baran, M.; Jakiela, R. et al.
Object Type: Article
System: The UNT Digital Library
Effects of Te inclusions on the performance of CdZnTe radiation detectors (open access)

Effects of Te inclusions on the performance of CdZnTe radiation detectors

Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beamline recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.
Date: October 19, 2008
Creator: Bolotnikov, A. E.; Abdul-Jabber, N. M.; Babalola, O. S.; Camarda, G. S.; Cui, Y.; Hossain, A. M. et al.
Object Type: Article
System: The UNT Digital Library
Good electrical contacts for high resistivity (Cd,Mn)Te crystals (open access)

Good electrical contacts for high resistivity (Cd,Mn)Te crystals

We consider that semi-insulating (Cd,Mn)Te crystals may well successfully replace the commonly used (Cd,Zn)Te crystals as a material for manufacturing large-area X- and gamma-ray detectors. The Bridgman growth method yields good quality and high-resistivity (10{sup 9}-10{sup 10} {Omega}-cm) crystals of (Cd,Mn)Te:V. Doping with vanadium ({approx} 10{sup 16} cm{sup -3}), which acts as a compensating agent, and annealing in cadmium vapors, which reduces the number of cadmium vacancies in the as-grown crystal, ensure this high resistivity. Detector applications of the crystals require satisfactory electrical contacts. Hence, we explored techniques of ensuring good electrical contacts to semi-insulating (Cd,Mn)Te crystals. Our findings are reported here. Before depositing the contact layers, we prepared an 'epi-ready' surface of the crystal platelet by a procedure described earlier for various tellurium-based II-VI compound crystals. A molecular beam epitaxy (MBE) apparatus was used to deposit various types of contact layers: Monocrystalline semiconductor layers, amorphous- and nanocrystalline semiconductor layers, and metal layers were studied. We employed ZnTe heavily doped ({approx} 10{sup 18} cm{sup -3}) with Sb, and CdTe heavily doped ({approx} 10{sup 17} cm{sup -3}) with In as the semiconductors to create contact layers that subsequently enable good contact (with a narrow, tunneling barrier) to the Au layer that …
Date: October 19, 2008
Creator: Witkowska-Baran, M.; Mycielski, A.; Kochanowska, D.; Szadkowski, A. J.; Jakiela, r.; Witkowska, B. et al.
Object Type: Article
System: The UNT Digital Library
Investigation of Charge Transport Properties of CdZnTe Detectors with Synchrotron X-ray Radiation (open access)

Investigation of Charge Transport Properties of CdZnTe Detectors with Synchrotron X-ray Radiation

Various internal defects, such as Te inclusions, twin boundaries, dislocation, etc., are prevalent in as-grown CdZnTe (CZT) crystals, which affect the charge transport properties of CZT crystals and, therefore, worsen the performance of CZT detectors. In order to develop high quality CZT detectors, it is imperative to clarify the effects of internal defects on the charge transport properties of CZT. Simple flood illumination with nuclear radiation source cannot reveal the nature of highly localized defects in CZT. Therefore, at Brookhaven's National Synchrotron Light Source (NSLS), we have developed a unique testing system for micro-scale defect investigation of CZT, which employs an X-ray beam collimated with the spatial resolution as small as 3 x 3 {micro}m{sup 2}, a microscopic size comparable to the scale of common defects in CZT. This powerful tool enables us to investigate the effect of internal defects on charge transport properties of CZT in detail.
Date: October 19, 2008
Creator: Yang, G.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Hossain, A. & James, R. B.
Object Type: Article
System: The UNT Digital Library
Tellurium precipitates in (Cd,Mn)Te:V crystals: Effects of annealing (open access)

Tellurium precipitates in (Cd,Mn)Te:V crystals: Effects of annealing

We suggest that (Cd,Mn)Te is a suitable material for fabricating gamma- and X-ray detectors. Our investigations, reported here, are focused on producing high-quality (Cd,Mn)Te crystals with high resistivity (10{sup 9} {Omega}-cm) by the Bridgman method. As-grown, undoped (Cd,Mn)Te crystals are typically p-type, signifying that they contain excess Cd vacancies (acting as acceptors), accumulated during growth. Doping with vanadium atoms, which function as compensating centers, results in a semi-insulating material (Cd,Mn)Te:V. Properly annealing the platelets in cadmium vapors at uniform temperature reduces the number of cadmium vacancies, and lowers the level of the vanadium doping required for compensation. We found that annealing in cadmium vapors not only decreases the concentration of the native cadmium vacancies but also improves the crystal's quality. Infrared observations of the interior of the samples show that annealing in a temperature gradient perpendicular to the platelet has an additional effect, viz., the tellurium precipitates migrate towards the side where the temperature is higher. We demonstrate, with IR pictures of monocrystalline (Cd,Mn)Te:V platelets cut parallel to the (111) crystal planes, the influence on tellurium inclusions and precipitates of various conditions of annealing in cadmium vapors.
Date: October 19, 2008
Creator: Kochanowska,D.; Mycielski, A.; Witkowska-Baran, M.; Szadkowski, A.; Witkowska, B.; Kaliszek, W. et al.
Object Type: Article
System: The UNT Digital Library
Thermal Neutron Detectors with Discrete Anode Pad Readout (open access)

Thermal Neutron Detectors with Discrete Anode Pad Readout

A new two-dimensional thermal neutron detector concept that is capable of very high rates is being developed. It is based on neutron conversion in {sup 3}He in an ionization chamber (unity gas gain) that uses only a cathode and anode plane; there is no additional electrode such as a Frisch grid. The cathode is simply the entrance window, and the anode plane is composed of discrete pads, each with their own readout electronics implemented via application specific integrated circuits. The aim is to provide a new generation of detectors with key characteristics that are superior to existing techniques, such as higher count rate capability, better stability, lower sensitivity to background radiation, and more flexible geometries. Such capabilities will improve the performance of neutron scattering instruments at major neutron user facilities. In this paper, we report on progress with the development of a prototype device that has 48 x 48 anode pads and a sensitive area of 24cm x 24cm.
Date: October 19, 2008
Creator: Yu,B. & Schaknowski, N.A., Smith, G.C., DeGeronimo, G., Vernon, E.O.
Object Type: Article
System: The UNT Digital Library
2007 Time_Dependent Density-Functional Therory (July 15-20, 2007 Colby College, Maine) (open access)

2007 Time_Dependent Density-Functional Therory (July 15-20, 2007 Colby College, Maine)

Time-dependent density-functional theory (TDDFT) provides an efficient, elegant, and formally exact way of describing the dynamics of interacting many-body quantum systems, circumventing the need for solving the full time-dependent Schroedinger equation. In the 20 years since it was first rigorously established in 1984, the field of TDDFT has made rapid and significant advances both formally as well as in terms of successful applications in chemistry, physics and materials science. Today, TDDFT has become the method of choice for calculating excitation energies of complex molecules, and is becoming increasingly popular for describing optical and spectroscopic properties of a variety of materials such as bulk solids, clusters and nanostructures. Other growing areas of applications of TDDFT are nonlinear dynamics of strongly excited electronic systems and molecular electronics. The purpose and scope of this Gordon Research Conference is to provide a platform for discussing the current state of the art of the rapidly progressing, highly interdisciplinary field of TDDFT, to identify and debate open questions, and to point out new promising research directions. The conference will bring together experts with a diverse background in chemistry, physics, and materials science.
Date: September 19, 2008
Creator: Gray, Ullrich Carsten Nancy Ryan
Object Type: Article
System: The UNT Digital Library
CRUCIBLE TESTING OF TANK 48 RADIOACTIVE WASTE SAMPLE USING FBSR TECHNOLOGY FOR ORGANIC DESTRUCTION (open access)

CRUCIBLE TESTING OF TANK 48 RADIOACTIVE WASTE SAMPLE USING FBSR TECHNOLOGY FOR ORGANIC DESTRUCTION

The purpose of crucible scale testing with actual radioactive Tank 48H material was to duplicate the test results that had been previously performed on simulant Tank 48H material. The earlier crucible scale testing using simulants was successful in demonstrating that bench scale crucible tests produce results that are indicative of actual Fluidized Bed Steam Reforming (FBSR) pilot scale tests. Thus, comparison of the results using radioactive Tank 48H feed to those reported earlier with simulants would then provide proof that the radioactive tank waste behaves in a similar manner to the simulant. Demonstration of similar behavior for the actual radioactive Tank 48H slurry to the simulant is important as a preliminary or preparation step for the more complex bench-scale steam reformer unit that is planned for radioactive application in the Savannah River National Laboratory (SRNL) Shielded Cells Facility (SCF) later in 2008. The goals of this crucible-scale testing were to show 99% destruction of tetraphenylborate and to demonstrate that the final solid product produced is sodium carbonate. Testing protocol was repeated using the specifications of earlier simulant crucible scale testing, that is sealed high purity alumina crucibles containing a pre-carbonated and evaporated Tank 48H material. Sealing of the crucibles was …
Date: September 19, 2008
Creator: Hammond, C & William Pepper, W
Object Type: Report
System: The UNT Digital Library
An Enquiry Concerning Charmless Semileptonic Decays of Bottom Mesons (open access)

An Enquiry Concerning Charmless Semileptonic Decays of Bottom Mesons

The branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup {+-}}, {pi}{sup 0}, {eta} and {eta}{prime} and {ell} is an electron or muon, are measured with B{sup 0} and B{sup {+-}} mesons found in the recoil of a second B meson decaying as B {yields} D{ell}{nu}{sub {ell}} or B {yields} D*{ell}{nu}{sub {ell}}. The measurements are based on a data set of 348 fb{sup -1} of e{sup +}e{sup -} collisions at {radical}s = 10.58 GeV recorded with the BABAR detector. Assuming isospin symmetry, measured pionic branching fractions are combined into {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}. First evidence of the B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} decay is seen; its branching fraction is measured to be {Beta}(B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}}) = (0.64 {+-} 0.20{sub (stat)} {+-} 0.03{sub (syst)}) x 10{sup -4}. It is determined that {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence. Partial branching fractions for the pionic decays in ranges of the momentum transfer and various published calculations of the B {yields} {pi} hadronic form factor are used to obtain values …
Date: September 19, 2008
Creator: Chaisanguanthum, Kris Somboon & /SLAC, /Harvard U.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments (open access)

Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments

In adult tissues, multi-potent progenitor cells are some of the most primitive members of the developmental hierarchies that maintain homeostasis. That progenitors and their more mature progeny share identical genomes, suggests that fate decisions are directed by interactions with extrinsic soluble factors, ECM, and other cells, as well as physical properties of the ECM. To understand regulation of fate decisions, therefore, would require a means of understanding carefully choreographed combinatorial interactions. Here we used microenvironment protein microarrays to functionally identify combinations of cell-extrinsic mammary gland proteins and ECM molecules that imposed specific cell fates on bipotent human mammary progenitor cells. Micropatterned cell culture surfaces were fabricated to distinguish between the instructive effects of cell-cell versus cell-ECM interactions, as well as constellations of signaling molecules; and these were used in conjunction with physiologically relevant 3 dimensional human breast cultures. Both immortalized and primary human breast progenitors were analyzed. We report on the functional ability of those proteins of the mammary gland that maintain quiescence, maintain the progenitor state, and guide progenitor differentiation towards myoepithelial and luminal lineages.
Date: September 19, 2008
Creator: LaBarge, Mark A; Nelson, Celeste M; Villadsen, Rene; Fridriksdottir, Agla; Ruth, Jason R; Stampfer, Martha R et al.
Object Type: Article
System: The UNT Digital Library
Self-doping effects in epitaxially grown graphene (open access)

Self-doping effects in epitaxially grown graphene

Self-doping in graphene has been studied by examining single-layer epitaxially grown graphene samples with differing characteristic lateral terrace widths. Low energy electron microscopy was used to gain real-space information about the graphene surface morphology, which was compared with data obtained by angle-resolved photoemission spectroscopy to study the effect of the monolayer graphene terrace width on the low energy dispersions. By altering the graphene terrace width, we report significant changes in the electronic structure and quasiparticle relaxation time of the material, in addition to a terrace width-dependent doping effect.
Date: September 19, 2008
Creator: Siegel, David A.; Zhou, Shuyun Y.; El Gabaly, Farid; Fedorov, Alexei V.; Schmid, Andreas K. & Lanzara, Alessandra
Object Type: Article
System: The UNT Digital Library
Development of a CMOS SOI Pixel Detector (open access)

Development of a CMOS SOI Pixel Detector

We have developed a monolithic radiation pixel detector using silicon on insulator (SOI) with a commercial 0.15 {micro}m fully-depleted-SOI technology and a Czochralski high resistivity silicon substrate in place of a handle wafer. The SOI TEG (Test Element Group) chips with a size of 2.5 x 2.5 mm{sup 2} consisting of 20 x 20 {micro}m{sup 2} pixels have been designed and manufactured. Performance tests with a laser light illumination and a {beta} ray radioactive source indicate successful operation of the detector. We also briefly discuss the back gate effect as well as the simulation study.
Date: August 19, 2008
Creator: Arai, Y.; Hazumi, M.; Ikegami, Y.; Kohriki, T.; Tajima, O.; Terada, S. et al.
Object Type: Article
System: The UNT Digital Library
Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence (open access)

Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence

The effects of flux surface shape on the gyrokinetic stability and transport of tokamak plasmas are studied using the GS2 code [M. Kotschenreuther, G. Rewoldt, and W.M. Tang, Comput. Phys. Commun. 88, 128 (1995); W. Dorland, F. Jenko, M. Kotschenreuther, and B.N. Rogers, Phys. Rev. Lett. 85, 5579 (2000)]. Studies of the scaling of nonlinear turbulence with shaping parameters are performed using analytic equilibria based on interpolations of representative shapes of the Joint European Torus (JET) [P.H. Rebut and B.E. Keen, Fusion Technol. 11, 13 (1987)]. High shaping is found to be a stabilizing influence on both the linear ion-temperature-gradient (ITG) instability and the nonlinear ITG turbulence. For the parameter regime studied here, a scaling of the heat flux with elongation of χ ∼ ℵ-1.5 or ℵ-2.0, depending on the triangularity, is observed at fixed average temperature gradient. While this is not as strong as empirical elongation scalings, it is also found that high shaping results in a larger Dimits upshift of the nonlinear critical temperature gradient due to an enhancement of the Rosenbluth-Hinton residual zonal flows.
Date: August 19, 2008
Creator: E.A. Belli, G.W. Hammett and W. Dorland
Object Type: Report
System: The UNT Digital Library
EVALUATION OF SULFATE ATTACK ON SALTSTONE VAULT CONCRETE AND SALTSTONESIMCO TECHNOLOGIES, INC. PART1 FINAL REPORT (open access)

EVALUATION OF SULFATE ATTACK ON SALTSTONE VAULT CONCRETE AND SALTSTONESIMCO TECHNOLOGIES, INC. PART1 FINAL REPORT

This report summarizes the preliminary results of a durability analysis performed by SIMCO Technologies Inc. to assess the effects of contacting saltstone Vaults 1/4 and Disposal Unit 2 concretes with highly alkaline solutions containing high concentrations of dissolved sulfate. The STADIUM{reg_sign} code and data from two surrogate concretes which are similar to the Vaults 1/4 and Disposal Unit 2 concretes were used in the preliminary durability analysis. Simulation results for these surrogate concrete mixes are provided in this report. The STADIUM{reg_sign} code will be re-run using transport properties measured for the SRS Vaults 1/4 and Disposal Unit 2 concrete samples after SIMCO personnel complete characterization testing on samples of these materials. Simulation results which utilize properties measured for samples of Vaults 1/4 and Disposal Unit 2 concretes will be provided in Revision 1 of this report after property data become available. The modeling performed to date provided the following information on two concrete mixes that will be used to support the Saltstone PA: (1) Relationship between the rate of advancement of the sulfate front (depth of sulfate ion penetration into the concrete) and the rate of change of the concrete permeability and diffusivity. (2) Relationship between the sulfate ion concentration …
Date: August 19, 2008
Creator: Langton, C
Object Type: Report
System: The UNT Digital Library
Final Report - Independent Verification Survey Report for the Waste Loading Area, Former Hazardous Waste Management Facility, Brookhaven National Laboratory, Upton, New York (open access)

Final Report - Independent Verification Survey Report for the Waste Loading Area, Former Hazardous Waste Management Facility, Brookhaven National Laboratory, Upton, New York

The objective of the verification survey was to obtain evidence by means of measurements and sampling to confirm that the final radiological conditions were less than the established release criteria. This objective was achieved via multiple verification components including document reviews to determine the accuracy and adequacy of FSS documentation.
Date: August 19, 2008
Creator: Weaver, P. C.
Object Type: Report
System: The UNT Digital Library