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Population-based analysis of POT1 variants in a cutaneous melanoma case–control cohort (open access)

Population-based analysis of POT1 variants in a cutaneous melanoma case–control cohort

Article describes how pathogenic germline variants in the protection of telomeres 1 gene (POT1) have been associated with predisposition to a range of tumor types, including melanoma, glioma, leukemia and cardiac angiosarcoma. The authors sequenced all coding exons of the POT1 gene in 2928 European-descent melanoma cases and 3298 controls, identifying 43 protein-changing genetic variants.
Date: December 20, 2022
Creator: Simonin-Wilmer, Irving; Ossio, Raul; Leddin, Emmett M.; Harland, Mark; Pooley, Karen A.; Martil de la Garza, Mauricio Gerardo et al.
System: The UNT Digital Library
Peptide signaling molecules CLE5 and CLE6 affect Arabidopsis leaf shape downstream of leaf patterning transcription factors and auxin (open access)

Peptide signaling molecules CLE5 and CLE6 affect Arabidopsis leaf shape downstream of leaf patterning transcription factors and auxin

Article describes a role in Arabidopsis leaf development for two members of the CLAVATA3/ESR‐RELATED peptide family, CLE5 and CLE6, which lie adjacent to each other on chromosome 2.
Date: December 20, 2018
Creator: DiGennaro, Peter; Grienenberger, Etienne; Dao, Thai Q.; Jun, Ji Hyung & Fletcher, Jennifer C.
System: The UNT Digital Library
Resistant energy analysis of self-pulling process during dropwise condensation on superhydrophobic surfaces (open access)

Resistant energy analysis of self-pulling process during dropwise condensation on superhydrophobic surfaces

Article describes an energy-based analysis on the formation and growth of condensate droplets on two-tier superhydrophobic surfaces, which are fabricated by decorating carbon nanotubes (CNTs) onto microscale fluorinated pillars.
Date: December 20, 2018
Creator: Vandadi, Aref; Zhao, Lei & Cheng, Jiangtao
System: The UNT Digital Library
Extraordinary Light-Trapping Enhancement in Silicon Solar Cell Patterned with Graded Photonic Super-Crystals (open access)

Extraordinary Light-Trapping Enhancement in Silicon Solar Cell Patterned with Graded Photonic Super-Crystals

This article explores light-trapping enhancement in newly discovered graded photonic super-crystals (GPSCs) with dual periodicity and dual basis.
Date: December 7, 2017
Creator: Hassan, Safaa; Lowell, David; Adewole, Murthada; George, David; Zhang, Hualiang & Lin, Yuankun
System: The UNT Digital Library

Understanding How Low-Socioeconomic Status Households Cope With Health Shocks: An Analysis of Multi-Sector Linked Data

This article links data from a nonprofit food distribution center, electronic medical records from a safety-net healthcare system, and publicly available residential appraisals for more than 3,000 households to provide insight into how low-socioeconomic status households cope with health shocks experienced by resident adults.
Date: December 20, 2016
Creator: Leonard, Tammy; Hughes, Amy & Pruitt, Sandi L.
System: The UNT Digital Library
One System Integrated Project Team: Retrieval And Delivery Of The Hanford Tank Wastes For Vitrification In The Waste Treatment Plant (open access)

One System Integrated Project Team: Retrieval And Delivery Of The Hanford Tank Wastes For Vitrification In The Waste Treatment Plant

The One System Integrated Project Team (IPT) was formed in late 2011 as a way for improving the efficiency of delivery and treatment of highly radioactive waste stored in underground tanks at the U.S. Department of Energy's (DOE's) 586-square-mile Hanford Site in southeastern Washington State. The purpose of the One System IPT is to improve coordination and integration between the Hanford's Waste Treatment Plant (WTP) contractor and the Tank Operations Contractor (TOC). The vision statement is: One System is a WTP and TOC safety conscious team that, through integrated management and implementation of risk-informed decision and mission-based solutions, will enable the earliest start of safe and efficient treatment of Hanford's tank waste, to protect the Columbia River, environment and public. The IPT is a formal collaboration between Bechtel National, Inc. (BNI), which manages design and construction of the WTP for the U.S. Department of Energy's Office of River Protection (DOEORP), and Washington River Protection Solutions (WRPS), which manages the TOC for ORP. More than fifty-six (56) million gallons of highly radioactive liquid waste are stored in one hundred seventy-seven (177) aging, underground tanks. Most of Hanford's waste tanks - one hundred forty-nine (149) of them - are of an old …
Date: December 20, 2012
Creator: Harp, Benton J.; Kacich, Richard M. & Skwarek, Raymond J.
System: The UNT Digital Library
Thermal Analysis for Ion-Exchange Column System (open access)

Thermal Analysis for Ion-Exchange Column System

Models have been developed to simulate the thermal characteristics of crystalline silicotitanate ion exchange media fully loaded with radioactive cesium either in a column configuration or distributed within a waste storage tank. This work was conducted to support the design and operation of a waste treatment process focused on treating dissolved, high-sodium salt waste solutions for the removal of specific radionuclides. The ion exchange column will be installed inside a high level waste storage tank at the Savannah River Site. After cesium loading, the ion exchange media may be transferred to the waste tank floor for interim storage. Models were used to predict temperature profiles in these areas of the system where the cesium-loaded media is expected to lead to localized regions of elevated temperature due to radiolytic decay. Normal operating conditions and accident scenarios (including loss of solution flow, inadvertent drainage, and loss of active cooling) were evaluated for the ion exchange column using bounding conditions to establish the design safety basis. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. In-tank modeling results revealed that an idealized hemispherical mound …
Date: December 20, 2012
Creator: Lee, Si Y. & King, William D.
System: The UNT Digital Library
Carbon-Oxygen Bond Formation via Organometallic Baeyer-Villiger Transformations: A Computational Study on the Impact of Metal Identity (open access)

Carbon-Oxygen Bond Formation via Organometallic Baeyer-Villiger Transformations: A Computational Study on the Impact of Metal Identity

Article discussing a computational study on the impact of metal identity and carbon-oxygen bond formation via organometallic Baeyer-Villiger transformations.
Date: December 20, 2011
Creator: Figg, Travis M.; Webb, Joanna R.; Cundari, Thomas R., 1964- & Gunnoe, T. Brent
System: The UNT Digital Library
Observational Evidence of Quasar Feedback Quenching Star Formation at High Redshift (open access)

Observational Evidence of Quasar Feedback Quenching Star Formation at High Redshift

This Letter to the Editor discusses an observational proof of quasar feedback quenching the star formation at high redshift.
Date: December 20, 2011
Creator: Cano-Díaz, Mariana; Maiolino, Roberto; Marconi, Alessandro; Netzer, Hagai; Shemmer, Ohad & Cresci, Giovanni
System: The UNT Digital Library
Plasma potential mapping of high power impulse magnetron sputtering discharges (open access)

Plasma potential mapping of high power impulse magnetron sputtering discharges

Pulsed emissive probe techniques have been used to determine the plasma potential distribution of high power impulse magnetron sputtering (HiPIMS) discharges. An unbalanced magnetron with a niobium target in argon was investigated for pulse length of 100 μs at a pulse repetition rate of 100 Hz, giving a peak current of 170 A. The probe data were taken with a time resolution of 20 ns and a spatial resolution of 1 mm. It is shown that the local plasma potential varies greatly in space and time. The lowest potential was found over the target’s racetrack, gradually reaching anode potential (ground) several centimeters away from the target. The magnetic pre-sheath exhibits a funnel-shaped plasma potential resulting in an electric field which accelerates ions toward the racetrack. In certain regions and times, the potential exhibits weak local maxima which allow for ion acceleration to the substrate. Knowledge of the local E and static B fields lets us derive the electrons’ E×B drift velocity, which is about 105 m/s and shows structures in space and time.
Date: December 20, 2011
Creator: Rauch, Albert; Mendelsberg, Rueben J.; Sanders, Jason M. & Anders, Andre
System: The UNT Digital Library
Relation Between Electric and Magnetic Field Structures and Their Proton Beam Images (open access)

Relation Between Electric and Magnetic Field Structures and Their Proton Beam Images

None
Date: December 20, 2011
Creator: Kugland, N. L.; Ryutov, D. D.; Plechaty, C.; Ross, J. S. & Park, H.
System: The UNT Digital Library
Surface and waveguide Josephson plasma waves in slabs of layered superconductors (open access)

Surface and waveguide Josephson plasma waves in slabs of layered superconductors

Article discussing surface and waveguide Josephson plasma waves in slabs of layered superconductors.
Date: December 20, 2011
Creator: Slipchenko, T. M.; Kadygrob, D. V.; Bogdanis, D.; Yampol'skii, V. A. & Krokhin, Arkadii A.
System: The UNT Digital Library
Automatic Fault Characterization via Abnormality-Enhanced Classification (open access)

Automatic Fault Characterization via Abnormality-Enhanced Classification

Enterprise and high-performance computing systems are growing extremely large and complex, employing hundreds to hundreds of thousands of processors and software/hardware stacks built by many people across many organizations. As the growing scale of these machines increases the frequency of faults, system complexity makes these faults difficult to detect and to diagnose. Current system management techniques, which focus primarily on efficient data access and query mechanisms, require system administrators to examine the behavior of various system services manually. Growing system complexity is making this manual process unmanageable: administrators require more effective management tools that can detect faults and help to identify their root causes. System administrators need timely notification when a fault is manifested that includes the type of fault, the time period in which it occurred and the processor on which it originated. Statistical modeling approaches can accurately characterize system behavior. However, the complex effects of system faults make these tools difficult to apply effectively. This paper investigates the application of classification and clustering algorithms to fault detection and characterization. We show experimentally that naively applying these methods achieves poor accuracy. Further, we design novel techniques that combine classification algorithms with information on the abnormality of application behavior to …
Date: December 20, 2010
Creator: Bronevetsky, G; Laguna, I & de Supinski, B R
System: The UNT Digital Library
Developmental long trace profiler using optimally aligned mirror based pentaprism (open access)

Developmental long trace profiler using optimally aligned mirror based pentaprism

A low-budget surface slope measuring instrument, the Developmental Long Trace Profiler (DLTP), was recently brought into operation at the Advanced Light Source Optical Metrology Laboratory. The instrument is based on a precisely calibrated autocollimator and a movable pentaprism. The capability of the DLTP to achieve sub-microradian surface slope metrology has been verified via cross-comparison measurements with other high-performance slope measuring instruments when measuring the same high-quality test optics. In the present work, a further improvement of the DLTP is achieved by replacing the existing bulk pentaprism with a specially designed mirror based pentaprism. A mirror based pentaprism offers the possibility to eliminate systematic errors introduced by inhomogeneity of the optical material and fabrication imperfections of a bulk pentaprism. We provide the details of the mirror based pentaprism design and describe an original experimental procedure for precision mutual alignment of the mirrors. The algorithm of the alignment procedure and its efficiency are verified with rigorous ray tracing simulations. Results of measurements of a spherically curved test mirror and a flat test mirror using the original bulk pentaprism are compared with measurements using the new mirror based pentaprism, demonstrating the improved performance.
Date: December 20, 2010
Creator: Barber, Samuel K.; Morrison, Gregory Y.; Yashchuk, Valeriy V.; Gubarev, Mikhail V.; Geckeler, Ralf D.; Buchheim, Jana et al.
System: The UNT Digital Library
A NORMETEX MODEL 15 M3/HR WATER VAPOR PUMPING TEST (open access)

A NORMETEX MODEL 15 M3/HR WATER VAPOR PUMPING TEST

Tests were performed using a Model 15 m{sup 3}/hr Normetex vacuum pump to determine if pump performance degraded after pumping a humid gas stream. An air feed stream containing 30% water vapor was introduced into the pump for 365 hours with the outlet pressure of the pump near the condensation conditions of the water. Performance of the pump was tested before and after the water vapor pumping test and indicated no loss in performance of the pump. The pump also appeared to tolerate small amounts of condensed water of short duration without increased noise, vibration, or other adverse indications. The Normetex pump was backed by a dual-head diaphragm pump which was affected by the condensation of water and produced some drift in operating conditions during the test.
Date: December 20, 2010
Creator: Klein, J.; Fowley, M. & Steeper, T.
System: The UNT Digital Library
SURFACE SYMMETRY ENERGY OF NUCLEAR ENERGY DENSITY FUNCTIONALS (open access)

SURFACE SYMMETRY ENERGY OF NUCLEAR ENERGY DENSITY FUNCTIONALS

We study the bulk deformation properties of the Skyrme nuclear energy density functionals. Following simple arguments based on the leptodermous expansion and liquid drop model, we apply the nuclear density functional theory to assess the role of the surface symmetry energy in nuclei. To this end, we validate the commonly used functional parametrizations against the data on excitation energies of superdeformed band-heads in Hg and Pb isotopes, and fission isomers in actinide nuclei. After subtracting shell effects, the results of our self-consistent calculations are consistent with macroscopic arguments and indicate that experimental data on strongly deformed configurations in neutron-rich nuclei are essential for optimizing future nuclear energy density functionals. The resulting survey provides a useful benchmark for further theoretical improvements. Unlike in nuclei close to the stability valley, whose macroscopic deformability hangs on the balance of surface and Coulomb terms, the deformability of neutron-rich nuclei strongly depends on the surface-symmetry energy; hence, its proper determination is crucial for the stability of deformed phases of the neutron-rich matter and description of fission rates for r-process nucleosynthesis.
Date: December 20, 2010
Creator: Nikolov, N.; Schunck, N.; Nazarewicz, W.; Bender, M. & Pei, J.
System: The UNT Digital Library
Boltzmann babies in the proper time measure (open access)

Boltzmann babies in the proper time measure

After commenting briefly on the role of the typicality assumption in science, we advocate a phenomenological approach to the cosmological measure problem. Like any other theory, a measure should be simple, general, well defined, and consistent with observation. This allows us to proceed by elimination. As an example, we consider the proper time cutoff on a geodesic congruence. It predicts that typical observers are quantum fluctuations in the early universe, or Boltzmann babies. We sharpen this well-known youngness problem by taking into account the expansion and open spatial geometry of pocket universes. Moreover, we relate the youngness problem directly to the probability distribution for observables, such as the temperature of the cosmic background radiation. We consider a number of modifications of the proper time measure, but find none that would make it compatible with observation.
Date: December 20, 2007
Creator: Bousso, Raphael; Bousso, Raphael; Freivogel, Ben & Yang, I-Sheng
System: The UNT Digital Library
Control of the Magnetic and Magnetotransport Properties of La0.67Sr0.33MnO3 Thin Films Through Epitaxial Strain (open access)

Control of the Magnetic and Magnetotransport Properties of La0.67Sr0.33MnO3 Thin Films Through Epitaxial Strain

The influence of epitaxial strain, in the form of tetragonal distortions, on the magnetic and magnetotransport properties of La{sub 0.67}Sr{sub 0.33}MnO{sub 3} thin films was studied. The tetragonal distortion (c/a ratio) was modulated through the choice of the substrate, ranging from c/a=1.007 on (001)-oriented (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} substrates to 0.952 on (110)-oriented GdScO{sub 3} substrates. In agreement with previous theoretical predictions, these large values of tensile strain cause the Curie temperature and the saturation magnetization to decrease, alter the temperature dependence of the resistivity and magnetoresistance, and increase the resistivity several orders of magnitude.
Date: December 20, 2007
Creator: Arenholz, Elke; Takamura, Y.; Chopdekar, R.V.; Arenholz, E. & Suzuki, Y.
System: The UNT Digital Library
Horizontal gene transfer and the evolution of transcriptionalregulation in Escherichia coli (open access)

Horizontal gene transfer and the evolution of transcriptionalregulation in Escherichia coli

Background: Most bacterial genes were acquired by horizontalgene transfer from other bacteria instead of being inherited bycontinuous vertical descent from an ancient ancestor}. To understand howthe regulation of these {acquired} genes evolved, we examined theevolutionary histories of transcription factors and of regulatoryinteractions from the model bacterium Escherichia coli K12. Results:Although most transcription factors have paralogs, these usually arose byhorizontal gene transfer rather than by duplication within the E. colilineage, as previously believed. In general, most neighbor regulators --regulators that are adjacent to genes that they regulate -- were acquiredby horizontal gene transfer, while most global regulators evolvedvertically within the gamma-Proteobacteria. Neighbor regulators wereoften acquired together with the adjacent operon that they regulate, sothe proximity might be maintained by repeated transfers (like "selfishoperons"). Many of the as-yet-uncharacterized (putative) regulators havealso been acquired together with adjacent genes, so we predict that theseare neighbor regulators as well. When we analyzed the histories ofregulatory interactions, we found that the evolution of regulation byduplication was rare, and surprisingly, many of the regulatoryinteractions that are shared between paralogs result from convergentevolution. Another surprise was that horizontally transferred genes aremore likely than other genes to be regulated by multiple regulators, andmost of this complex regulation probably evolved …
Date: December 20, 2007
Creator: Price, Morgan N.; Dehal, Paramvir S. & Arkin, Adam P.
System: The UNT Digital Library
Rho0 Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR (open access)

Rho0 Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR

Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR collaboration presents a measurement of {rho}{sup 0} and direct {pi}{sup +}{pi}{sup -} photoproduction in ultra-peripheral relativistic heavy ion collisions at {radical}s{sub NN} = 200 GeV. We observe both exclusive photoproduction and photoproduction accompanied by mutual Coulomb excitation. We find a coherent cross-section of {sigma}(AuAu {yields} Au*Au* {rho}{sup 0}) = 530 {+-} 19 (stat.) {+-} 57 (syst.) mb, in accord with theoretical calculations based on a Glauber approach, but considerably below the predictions of a color dipole model. The {rho}{sup 0} transverse momentum spectrum (p{sub T}{sup 2}) is fit by a double exponential curve including both coherent and incoherent coupling to the target nucleus; we find {sigma}{sub inc}/{sigma}{sub coh} = 0.29 {+-} 0.03 (stat.) {+-} 0.08 (syst.). The ratio of direct {pi}{sup +}{pi}{sup -} production is comparable to that observed in {gamma}p collisions at HERA, and appears to be independent of photon energy. Finally, the measured {rho}{sup 0} spin helicity matrix elements agree within errors with the expected s-channel helicity conservation.
Date: December 20, 2007
Creator: STAR Collaboration
System: The UNT Digital Library
TALC: A Simple C Language Extension For Improved Performance and Code Maintainability (open access)

TALC: A Simple C Language Extension For Improved Performance and Code Maintainability

None
Date: December 20, 2007
Creator: Keasler, J.; Jones, T. & Quinlan, D.
System: The UNT Digital Library
TEM Study of Fracturing in Spherical and Plate-like LiFePO4Particles (open access)

TEM Study of Fracturing in Spherical and Plate-like LiFePO4Particles

An investigation of fracturing in LiFePO{sub 4} particles as a function of the particle morphology and history is presented. Two types of samples, one subjected to electrochemical cycling and another to chemical delithiation are compared. We observe the formation of micro fractures parallel to low indexed lattice planes in both samples. The fracture surfaces are predominantly parallel to (100) planes in the chemically delithiated powder and (100) and (010) planes in the electrochemically cycled powder. A consideration of the threshold stresses for dislocation glide shows that particle geometry plays an important role in the observed behavior.
Date: December 20, 2007
Creator: Gabrisch, H.; Wilcox, J. & Doeff, M.M.
System: The UNT Digital Library
Enabling Strain Hardening Simulations with Dislocation Dynamics (open access)

Enabling Strain Hardening Simulations with Dislocation Dynamics

Numerical algorithms for discrete dislocation dynamics simulations are investigated for the purpose of enabling strain hardening simulations of single crystals on massively parallel computers. The algorithms investigated include the /(N) calculation of forces, the equations of motion, time integration, adaptive mesh refinement, the treatment of dislocation core reactions, and the dynamic distribution of work on parallel computers. A simulation integrating all of these algorithmic elements using the Parallel Dislocation Simulator (ParaDiS) code is performed to understand their behavior in concert, and evaluate the overall numerical performance of dislocation dynamics simulations and their ability to accumulate percents of plastic strain.
Date: December 20, 2006
Creator: Arsenlis, Athanasios; Cai, Wei; Tang, Meijie; Rhee, Moono; Oppelstrup, Tomas; Hommes, Gregg et al.
System: The UNT Digital Library
HANFORD CHEMICAL VAPORS WORKER CONCERNS & EXPOSURE EVALUATION (open access)

HANFORD CHEMICAL VAPORS WORKER CONCERNS & EXPOSURE EVALUATION

Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. Tank farm contractors are in the process of retrieving all remaining waste from aging single-shell tanks, some of which date to World War II, and transferring it to newer double-shell tanks. During the waste retrieval process, tank farm workers are potentially exposed to fugitive chemical vapors that can escape from tank headspaces and other emission points. The tanks are known to hold more than 1,500 different species of chemicals, in addition to radionuclides. Exposure assessments have fully characterized the hazards from chemical vapors in half of the tank farms. Extensive sampling and analysis has been done to characterize the chemical properties of hazardous waste and to evaluate potential health hazards of vapors at the ground surface, where workers perform maintenance and waste transfer activities. Worker concerns. risk communication, and exposure assessment are discussed, including evaluation of the potential hazards of complex mixtures of chemical vapors. Concentrations of vapors above occupational exposure limits-(OEL) were detected only at exhaust stacks and passive breather filter …
Date: December 20, 2006
Creator: Anderson, T. J.
System: The UNT Digital Library