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An inquiry into the uneven distribution of women’s HIV infection in rural Malawi (open access)

An inquiry into the uneven distribution of women’s HIV infection in rural Malawi

Article exploring elevated HIV levels in Malawi's Southern Region and the relationship between HIV levels, male circumcision, and marital histories.
Date: December 21, 2011
Creator: Poulin, Michelle
System: The UNT Digital Library
Single actomyosin motor interactions in skeletal muscle (open access)

Single actomyosin motor interactions in skeletal muscle

This article presents a study of intramuscular motion during contraction of skeletal muscle myofibrils.
Date: February 21, 2011
Creator: Földes-Papp, Zeno; Liao, Jeff Shih-Chu; Barbieri, Ben; Grycznski, Karol G.; Luchowski, Rafal; Gryczynski, Ignacy et al.
System: The UNT Digital Library
Optimization of nonlinear optical properties of ZnO micro and nanocrystals for biophotonics (open access)

Optimization of nonlinear optical properties of ZnO micro and nanocrystals for biophotonics

This article investigates the defects in ZnO created during its synthesis and its affect on the second and third-order nonlinear processes.
Date: July 21, 2011
Creator: Urban, Ben E.; Lin, Jie; Kumar, Os; Senthilkumar, Kasilingam; Fujita, Yasuhisa & Neogi, Arup
System: The UNT Digital Library
Atmospheric Stability Affects Wind Turbine Power Collection (open access)

Atmospheric Stability Affects Wind Turbine Power Collection

None
Date: April 21, 2011
Creator: Wharton, S & Lundquist, J K
System: The UNT Digital Library
Nonequilibrium candidate Monte Carlo: A new tool for equilibrium simulation (open access)

Nonequilibrium candidate Monte Carlo: A new tool for equilibrium simulation

None
Date: June 21, 2011
Creator: Nilmeier, J P; Crooks, G E; Minh, D L & Chodera, J D
System: The UNT Digital Library
Role of Singular Layers in the Plasma Response to Resonant Magnetic Perturbations (open access)

Role of Singular Layers in the Plasma Response to Resonant Magnetic Perturbations

None
Date: October 21, 2011
Creator: Waelbroeck, F L; Joseph, I; Nardon, E; Becoulet, M & Fitzpatrick, R
System: The UNT Digital Library
The r-process in Metal Poor Stars, and Black Hole Formation (open access)

The r-process in Metal Poor Stars, and Black Hole Formation

None
Date: July 21, 2011
Creator: Boyd, R. N.; Famiano, M. A.; Meyer, B. S.; Motizuki, Y.; Kajino, T. & Roederer, I. U.
System: The UNT Digital Library
Undistorted 3D microstructures in SU8 formed through two-photon polymerization (open access)

Undistorted 3D microstructures in SU8 formed through two-photon polymerization

This article presents the wavelength dependence of two-photon polymerization in SU-8 between 720-780 nm.
Date: September 21, 2011
Creator: Ohlinger, Kris; Lin, Yuankun; Poole, Zsolt & Chen, Kevin P.
System: The UNT Digital Library
The Lack of Torus Emission from BL Lacertae Objects: An Infrared View of Unification with WISE (open access)

The Lack of Torus Emission from BL Lacertae Objects: An Infrared View of Unification with WISE

This article uses data from the Wide-Field Infrared Survey Explorer to perform a statistical study on the mid-infrared properties of a large number of BL Lac objects.
Date: December 21, 2011
Creator: Plotkin, Richard M.; Anderson, Scott F.; Brandt, William Nielsen; Markoff, Sera; Shemmer, Ohad & Wu, Jianfeng
System: The UNT Digital Library
Illumina Unamplified Indexed Library Construction: An Automated Approach (open access)

Illumina Unamplified Indexed Library Construction: An Automated Approach

Manual library construction is a limiting factor in Illumina sequencing. Constructing libraries by hand is costly, time-consuming, low-throughput, and ergonomically hazardous, and constructing multiple libraries introduces risk of library failure due to pipetting errors. The ability to construct multiple libraries simultaneously in automated fashion represents significant cost and time savings. Here we present a strategy to construct up to 96 unamplified indexed libraries using Illumina TruSeq reagents and a Biomek FX robotic platform. We also present data to indicate that this library construction method has little or no risk of cross-contamination between samples.
Date: March 21, 2011
Creator: Hack, Christopher A.; Sczyrba, Alexander & Cheng, Jan-Fang
System: The UNT Digital Library
GROUNDWATER MONITORING REPORT GENERATION TOOLS - 12005 (open access)

GROUNDWATER MONITORING REPORT GENERATION TOOLS - 12005

Compliance with National and State environmental regulations (e.g. Resource Conservation and Recovery Act (RCRA) and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) aka SuperFund) requires Savannah River Site (SRS) to extensively collect and report groundwater monitoring data, with potential fines for missed reporting deadlines. Several utilities have been developed at SRS to facilitate production of the regulatory reports which include maps, data tables, charts and statistics. Components of each report are generated in accordance with complex sets of regulatory requirements specific to each site monitored. SRS developed a relational database to incorporate the detailed reporting rules with the groundwater data, and created a set of automation tools to interface with the information and generate the report components. These process improvements enhanced quality and consistency by centralizing the information, and have reduced manpower and production time through automated efficiencies.
Date: November 21, 2011
Creator: Lopez, N.
System: The UNT Digital Library
Ancient nature of alternative splicing and functions of introns (open access)

Ancient nature of alternative splicing and functions of introns

Using four genomes: Chamydomonas reinhardtii, Agaricus bisporus, Aspergillus carbonarius, and Sporotricum thermophile with EST coverage of 2.9x, 8.9x, 29.5x, and 46.3x respectively, we identified 11 alternative splicing (AS) types that were dominated by intron retention (RI; biased toward short introns) and found 15, 35, 52, and 63percent AS of multiexon genes respectively. Genes with AS were more ancient, and number of AS correlated with number of exons, expression level, and maximum intron length of the gene. Introns with tendency to be retained had either stop codons or length of 3n+1 or 3n+2 presumably triggering nonsense-mediated mRNA decay (NMD), but introns retained in major isoforms (0.2-6percent of all introns) were biased toward 3n length and stop codon free. Stopless introns were biased toward phase 0, but 3n introns favored phase 1 that introduced more flexible and hydrophilic amino acids on both ends of introns which would be less disruptive to protein structure. We proposed a model in which minor RI intron could evolve into major RI that could facilitate intron loss through exonization.
Date: March 21, 2011
Creator: Zhou, Kemin; Salamov, Asaf; Kuo, Alan; Aerts, Andrea & Grigoriev, Igor
System: The UNT Digital Library
DAFNE Setup And Operation With the Crab-Waist Collision Scheme (open access)

DAFNE Setup And Operation With the Crab-Waist Collision Scheme

In the second half of 2007 a major upgrade has been implemented on the Frascati DA{Phi}NE collider in order to test the novel idea of Crab-Waist collisions. New vacuum chambers and permanent quadrupole magnets have been designed, built and installed to realize the new configuration. At the same time the performances of relevant hardware components, such as fast injection kickers and shielded bellows have been improved relying on new design concepts. The collider has been successfully commissioned in this new configuration. The paper describes several experimental results about linear and non-linear optics setup and optimization, damping of beam-beam instabilities and discusses the obtained luminosity performances. DA{Phi}NE [1] is the Frascati lepton collider working at the c m. energy of the {Phi} meson resonance (1020). It came in operation in 2001 and till summer 2007 provided luminosity, in sequence, to three different experiments which logged a total integrated luminosity of {approx} 4.4 fb{sup -1}. During these years the collider reached its best performances in terms of luminosity and background (L{sub peak} = 1.6 x 10{sup 32} cm{sup -2}s{sup -1} L{sub day} {approx} 10 pb{sup -1}) by means of several successive upgrades, relying on the experience gathered during the collider operations and …
Date: October 21, 2011
Creator: Milardi, C.; Alesini, D.; Biagini, M. E.; Biscari, C.; Boni, R.; Boscolo, M. et al.
System: The UNT Digital Library
2011 RENEWABLE ENERGY: SOLAR FUELS GORDON RESEARCH CONFERENCE (open access)

2011 RENEWABLE ENERGY: SOLAR FUELS GORDON RESEARCH CONFERENCE

The conference will present and discuss current science that underlies solar fuels production, and will focus on direct production pathways for production. Thus, recent advances in design and understanding of molecular systems and materials for light capture and conversion of relevance for solar fuels will be discussed. An important set of topics will be homogeneous, heterogeneous and biological catalysts for the multi-electron processes of water oxidation, hydrogen production and carbon dioxide reduction to useful fuels. Also, progress towards integrated and scalable systems will be presented. Attached is a copy of the formal schedule and speaker program and the poster program.
Date: January 21, 2011
Creator: Hupp, Joseph
System: The UNT Digital Library
Simplified models for mask roughness induced LER (open access)

Simplified models for mask roughness induced LER

The ITRS requires < 1.2nm line-edge roughness (LER) for the 22nm half-pitch node. Currently, we can consistently achieve only about 3nm LER. Further progress requires understanding the principle causes of LER. Much work has already been done on how both the resist and LER on the mask effect the final printed LER. What is poorly understood, however, is the extent to which system-level effects such as mask surface roughness, illumination conditions, and defocus couple to speckle at the image plane, and factor into LER limits. Presently, mask-roughness induced LER is studied via full 2D aerial image modeling and subsequent analysis of the resulting image. This method is time consuming and cumbersome. It is, therefore, the goal of this research to develop a useful 'rule-of-thumb' analytic model for mask roughness induced LER to expedite learning and understanding.
Date: February 21, 2011
Creator: McClinton, Brittany & Naulleau, Patrick
System: The UNT Digital Library
Mapping Diffuse Seismicity Using Empirical Matched Field Processing Techniques (open access)

Mapping Diffuse Seismicity Using Empirical Matched Field Processing Techniques

The objective of this project is to detect and locate more microearthquakes using the empirical matched field processing (MFP) method than can be detected using only conventional earthquake detection techniques. We propose that empirical MFP can complement existing catalogs and techniques. We test our method on continuous seismic data collected at the Salton Sea Geothermal Field during November 2009 and January 2010. In the Southern California Earthquake Data Center (SCEDC) earthquake catalog, 619 events were identified in our study area during this time frame and our MFP technique identified 1094 events. Therefore, we believe that the empirical MFP method combined with conventional methods significantly improves the network detection ability in an efficient matter.
Date: January 21, 2011
Creator: Wang, J; Templeton, D C & Harris, D B
System: The UNT Digital Library
Quantitative evaluation of mask phase defects from through-focus EUV aerial images (open access)

Quantitative evaluation of mask phase defects from through-focus EUV aerial images

Mask defects inspection and imaging is one of the most important issues for any pattern transfer lithography technology. This is especially true for EUV lithography where the wavelength-specific properties of masks and defects necessitate actinic inspection for a faithful prediction of defect printability and repair performance. In this paper we will present a technique to obtain a quantitative characterization of mask phase defects from EUV aerial images. We apply this technique to measure the aerial image phase of native defects on a blank mask, measured with the SEMATECH Berkeley Actinic Inspection Tool (AIT) an EUV zoneplate microscope that operates at Lawrence Berkeley National Laboratory. The measured phase is compared with predictions made from AFM top-surface measurements of those defects. While amplitude defects are usually easy to recognize and quantify with standard inspection techniques like scanning electron microscopy (SEM), defects or structures that have a phase component can be much more challenging to inspect. A phase defect can originate from the substrate or from any level of the multilayer. In both cases its effect on the reflected field is not directly related to the local topography of the mask surface, but depends on the deformation of the multilayer structure. Using the …
Date: February 21, 2011
Creator: Mochi, Iacopo; Yamazoe, Kenji; Neureuther, Andrew & Goldberg, Kenneth A.
System: The UNT Digital Library
Absorber height effects on SWA restrictions and 'Shadow' LER (open access)

Absorber height effects on SWA restrictions and 'Shadow' LER

As extreme-ultraviolet lithography (EUVL) approaches introduction at the 22-nm half-pitch node, several key aspects of absorber height effects remain unexplored. In particular, sidewall angle (SWA) restrictions based on the height of the mask absorber has not yet been clearly defined. In addition, the effects of absorber height on line-edge roughness (LER) from shadowing has not been examined. We make an initial investigation into how tight SWA constraints are and the extent to which shadow LER alters basic LER. Our approach to SWA aims to find SWA restrictions based on 10% of the total CD error budget (10% of CD). Thus, we allot the SWA budget a {+-}0.2nm tolerance for 22nm half-pitch. New with EUVL is the off-axis illumination system. One potential pitfall that must be carefully monitored is the effect of mask absorber height blocking light from reaching, and therefore, correctly detecting, the base edge position of a feature. While mask features can correctly compensate sizing to target at the wafer, the effects of this shadowing on LER have not yet been investigated. Specifically, shadow LER may exacerbate or mitigate the inherent LER on the mask. Shadowing may also cause a difference in the observed LER on the right and …
Date: February 21, 2011
Creator: McClinton, Brittany & Naulleau, Patrick
System: The UNT Digital Library
Time-Resolved Synchrotron X-ray Diffraction on Pulse Laser Heated Iron in Diamond Anvil Cell (open access)

Time-Resolved Synchrotron X-ray Diffraction on Pulse Laser Heated Iron in Diamond Anvil Cell

The authors present time-resolved synchrotron x-ray diffraction to probe the {var_epsilon}-{delta} phase transition of iron during pulse-laser heating in a diamond anvil cell. The system utilizes a monochromatic synchrotron x-ray beam, a two-dimensional pixel array x-ray detector and a dual beam, double side laser-heating system. Multiple frames of the diffraction images are obtained in real-time every 22 ms over 500 ms of the entire pulse heating period. The results show the structural evolution of iron phases at 17 GPa, resulting in thermal expansion coefficient 1/V({Delta}V/{Delta}T){sub p} = 7.1 * 10{sup -6}/K for {var_epsilon}-Fe and 2.4 * 10{sup -5}/K for {gamma}-Fe, as well as the evidence for metastability of {gamma}-Fe at low temperatures below the {var_epsilon}-{gamma} phase boundary.
Date: September 21, 2011
Creator: Yoo, C. S.; Wei, H.; Dias, R.; Shen, G.; Smith, J.; Chen, J. Y. et al.
System: The UNT Digital Library
Parity Doubling and the S Parameter Below the Conformal Window (open access)

Parity Doubling and the S Parameter Below the Conformal Window

We describe a lattice simulation of the masses and decay constants of the lowest-lying vector and axial resonances, and the electroweak S parameter, in an SU(3) gauge theory with N{sub f} = 2 and 6 fermions in the fundamental representation. The spectrum becomes more parity doubled and the S parameter per electroweak doublet decreases when N{sub f} is increased from 2 to 6, motivating study of these trends as N{sub f} is increased further, toward the critical value for transition from confinement to infrared conformality.
Date: October 21, 2011
Creator: Appelquist, T; Babich, R; Brower, R C; Cheng, M; Clark, M A; Cohen, S D et al.
System: The UNT Digital Library
Particle Physics Outreach to Secondary Education (open access)

Particle Physics Outreach to Secondary Education

This review summarizes exemplary secondary education and outreach programs of the particle physics community. We examine programs from the following areas: research experiences, high-energy physics data for students, informal learning for students, instructional resources, and professional development. We report findings about these programs' impact on students and teachers and provide suggestions for practices that create effective programs from those findings. We also include some methods for assessing programs.
Date: November 21, 2011
Creator: Bardeen, Marjorie G.; Johansson, K. Erik & Young, M. Jean
System: The UNT Digital Library
Developing extensible lattice-Boltzmann simulators for general-purpose graphics-processing units (open access)

Developing extensible lattice-Boltzmann simulators for general-purpose graphics-processing units

Lattice-Boltzmann methods are versatile numerical modeling techniques capable of reproducing a wide variety of fluid-mechanical behavior. These methods are well suited to parallel implementation, particularly on the single-instruction multiple data (SIMD) parallel processing environments found in computer graphics processing units (GPUs). Although more recent programming tools dramatically improve the ease with which GPU programs can be written, the programming environment still lacks the flexibility available to more traditional CPU programs. In particular, it may be difficult to develop modular and extensible programs that require variable on-device functionality with current GPU architectures. This paper describes a process of automatic code generation that overcomes these difficulties for lattice-Boltzmann simulations. It details the development of GPU-based modules for an extensible lattice-Boltzmann simulation package - LBHydra. The performance of the automatically generated code is compared to equivalent purpose written codes for both single-phase, multiple-phase, and multiple-component flows. The flexibility of the new method is demonstrated by simulating a rising, dissolving droplet in a porous medium with user generated lattice-Boltzmann models and subroutines.
Date: December 21, 2011
Creator: Walsh, S C & Saar, M O
System: The UNT Digital Library
Chemistry Resolved Kinetic Flow Modeling of TATB Based Explosives (open access)

Chemistry Resolved Kinetic Flow Modeling of TATB Based Explosives

Detonation waves in insensitive, TATB based explosives are believed to have multi-time scale regimes. The initial burn rate of such explosives has a sub-microsecond time scale. However, significant late-time slow release in energy is believed to occur due to diffusion limited growth of carbon. In the intermediate time scale concentrations of product species likely change from being in equilibrium to being kinetic rate controlled. They use the thermo-chemical code CHEETAH linked to an ALE hydrodynamics code to model detonations. They term their model chemistry resolved kinetic flow as CHEETAH tracks the time dependent concentrations of individual species in the detonation wave and calculates EOS values based on the concentrations. A HE-validation suite of model simulations compared to experiments at ambient, hot, and cold temperatures has been developed. They present here a new rate model and comparison with experimental data.
Date: July 21, 2011
Creator: Vitello, P A; Fried, L E; Howard, W M; Levesque, G & Souers, P C
System: The UNT Digital Library
Status of the Neutralized Drift Compression Experiment (NDCX-II) (open access)

Status of the Neutralized Drift Compression Experiment (NDCX-II)

The Neutralized Drift Compression Experiment (NDCX-II) is an 11 M$ induction accelerator project currently in construction at Lawrence Berkeley National Laboratory for warm dense matter (WDM) experiments investigating the interaction of ion beams with matter at elevated temperature and pressure. The machine consists of a lithium injector, induction accelerator cells, diagnostic cells, a neutralized drift compression line, a final focus solenoid, and a target chamber. The induction cells and some of the pulsed power systems have been reused from the decommissioned Advanced Test Accelerator at Lawrence Livermore National Laboratory after refurbishment and modification. The machine relies on a sequence of acceleration waveforms to longitudinally compress the initial ion pulse from 600 ns to less than 1 ns in {approx} 12 m. Radial confinement of the beam is achieved with 2.5 T pulsed solenoids. In the initial hardware configuration, 50 nC of Li{sup +} will be accelerated to 1.25 MeV and allowed to drift-compress to a peak current of {approx}40 A. The project started in the summer of 2009. Construction of the accelerator will be completed in the fall of 2011 and will provide a worldwide unique opportunity for ion-driven warm dense matter experiments as well as research related to novel …
Date: April 21, 2011
Creator: Waldron, W. L. & Kwan, J. W.
System: The UNT Digital Library