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2001 Gordon Research Conference on Microbial Population Biology. Final progress report (open access)

2001 Gordon Research Conference on Microbial Population Biology. Final progress report

None
Date: August 3, 2001
Creator: Chao, Lin
System: The UNT Digital Library
2012 ELECTRODEPOSITION GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR, JULY 29 - AUGUST 3, 2012 (open access)

2012 ELECTRODEPOSITION GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR, JULY 29 - AUGUST 3, 2012

The 2012 Gordon Conference on Electrodeposition: Electrochemical Materials Synthesis and Applications will present cutting-edge research on electrodeposition with emphasis on (i) advances in basic science, (ii) developments in next-generation technologies, and (iii) new and emerging areas. The Conference will feature a wide range of topics, from atomic scale processes, nucleation and growth, thin film deposition, and electrocrystallization, to applications of electrodeposition in devices including microelectronics, batteries, solar energy, and fuel cells.
Date: August 3, 2013
Creator: Gewirth, Andrew
System: The UNT Digital Library
2012 MITOCHONDRIA AND CHLOROPLASTS GORDON RESEARCH CONFERENCE & GORDON RESEARCH SEMINAR, JULY 29 - AUGUST 3, 2012 (open access)

2012 MITOCHONDRIA AND CHLOROPLASTS GORDON RESEARCH CONFERENCE & GORDON RESEARCH SEMINAR, JULY 29 - AUGUST 3, 2012

The 2012 Gordon Research Conference on Mitochondria and Chloroplasts will assemble an international group of scientists investigating fundamental properties of these organelles, and their integration into broader physiological processes. The conference will emphasize the many commonalities between mitochondria and chloroplasts: their evolution from bacterial endosymbionts, their genomes and gene expression systems, their energy transducing membranes whose proteins derive from both nuclear and organellar genes, the challenge of maintaining organelle integrity in the presence of the reactive oxygen species that are generated during energy transduction, their incorporation into organismal signaling pathways, and more. The conference will bring together investigators working in animal, plant, fungal and protozoan systems who specialize in cell biology, genetics, biochemistry, physiology, proteomics, genomics, and structural biology. As such, this conference will provide a unique forum that engenders cross-disciplinary discussions concerning the biogenesis, dynamics, and regulation of these key cellular structures. By fostering interactions among mammalian, fungal and plant organellar biologists, this conference also provides a conduit for the transmission of mechanistic insights obtained in model organisms to applications in medicine and agriculture. The 2012 conference will highlight areas that are moving rapidly and emerging themes. These include new insights into the ultrastructure and organization of the energy …
Date: August 3, 2012
Creator: Barkan, Alice
System: The UNT Digital Library
2012 RADIATION CHEMISTRY GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR, JULY 28, - AUGUST 3, 2012 (open access)

2012 RADIATION CHEMISTRY GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR, JULY 28, - AUGUST 3, 2012

The overarching objective of this conference is to catalyze the interchange of new ideas and recent discoveries within the basic radiation sciences of physics, chemistry, and biology, and to facilitate translating this knowledge to applications in medicine and industry. The 9 topics for the GRC are: "œFrom Energy Absorption to Disease", "œBiodosimetry after a Radiological Incident," "œTrack Structure and Low Energy Electrons," "Free Radical Processes in DNA and Proteins," "Irradiated Polymers for Industrial/ Medical Applications," "Space Radiation Chemistry/Biology," "Nuclear Power and Waste Management," "Nanoparticles and Surface Interfaces", and the "Young Investigator" session.
Date: August 3, 2012
Creator: LaVerne, y
System: The UNT Digital Library
6th international conference on biophysics and synchrotron radiation. Program/Abstracts (open access)

6th international conference on biophysics and synchrotron radiation. Program/Abstracts

This STI product consists of the Program/Abstracts book that was prepared for the participants in the Sixth International Conference on Biophysics and Synchrotron Radiation that was held August 4-8, 1998, at the Advanced Photon Source, Argonne National Laboratory. This book contains the full conference program and abstracts of the scientific presentations.
Date: August 3, 1999
Creator: Pittroff, Connie & Strasser, Susan Barr
System: The UNT Digital Library
Ab initio no core calculations of light nuclei and preludes to Hamiltonian quantum field theory (open access)

Ab initio no core calculations of light nuclei and preludes to Hamiltonian quantum field theory

Recent advances in ab initio quantum many-body methods and growth in computer power now enable highly precise calculations of nuclear structure. The precision has attained a level sufficient to make clear statements on the nature of 3-body forces in nuclear physics. Total binding energies, spin-dependent structure effects, and electroweak properties of light nuclei play major roles in pinpointing properties of the underlying strong interaction. Eventually,we anticipate a theory bridge with immense predictive power from QCD through nuclear forces to nuclear structure and nuclear reactions. Light front Hamiltonian quantum field theory offers an attractive pathway and we outline key elements.
Date: August 3, 2009
Creator: Vary, J. P.; Maris, P.; Shirokov, A. M.; Honkanen, H.; li, J.; Brodsky, S. J. et al.
System: The UNT Digital Library
Adsorption of Activated Nitrogen (open access)

Adsorption of Activated Nitrogen

The information obtained in this experiment was deduced by measuring the pumping speed as a function of the energy of the incident electrons and as a function of the energy which ions hit the surface.
Date: August 3, 1963
Creator: Donaldson, E E; Winters, H F & Horne, D E
System: The UNT Digital Library
Analyzing Unsatirated Flow Patterns in Fractured Rock Using an Integrated Modeling Approach (open access)

Analyzing Unsatirated Flow Patterns in Fractured Rock Using an Integrated Modeling Approach

Characterizing percolation patterns in unsaturated fractured rock has posed a greater challenge to modeling investigations than comparable saturated zone studies, because of the heterogeneous nature of unsaturated media and the great number of variables impacting unsaturated flow. This paper presents an integrated modeling methodology for quantitatively characterizing percolation patterns in the unsaturated zone of Yucca Mountain, Nevada, a proposed underground repository site for storing high-level radioactive waste. The modeling approach integrates a wide variety of moisture, pneumatic, thermal, and isotopic geochemical field data into a comprehensive three-dimensional numerical model for modeling analyses. It takes into account the coupled processes of fluid and heat flow and chemical isotopic transport in Yucca Mountain's highly heterogeneous, unsaturated fractured tuffs. Modeling results are examined against different types of field-measured data and then used to evaluate different hydrogeological conceptualizations and their results of flow patterns in the unsaturated zone. In particular, this model provides a much clearer understanding of percolation patterns and flow behavior through the unsaturated zone, both crucial issues in assessing repository performance. The integrated approach for quantifying Yucca Mountain's flow system is demonstrated to provide a practical modeling tool for characterizing flow and transport processes in complex subsurface systems.
Date: August 3, 2006
Creator: Wu, Y.S.; Lu, G.; Zhang, K.; Pan, L. & Bodvarsson, G.S.
System: The UNT Digital Library
The appreciation of stochastic motion in particle accelerators (open access)

The appreciation of stochastic motion in particle accelerators

A description is given of the analytic and numerical work, performed from July 1955 through August 1956, so as to develop, and then study, the process of making intense proton beams, suitable for colliding beams. It is shown how this investigation led, in a most natural way, to the realization that stochasticity can arise in a simple Hamiltonian system. Furthermore, the criterion for the onset of stochasticity was understood, and carefully studied, in two different situations. The first situation was the proposed (and subsequently used) ''stacking process'' for developing an intense beam, where stochasticity occurs as additional particles are added to the intense circulating beam. The second situation occurs when one seeks to develop ''stochastic accelerators'' in which particles are accelerated (continuously) by a collection of radio frequency systems. It was in the last connection that the well-known criterion for stochasticity, resonance overlap, was obtained.
Date: August 3, 2003
Creator: Symon, Keith & Sessler, Andrew
System: The UNT Digital Library
Aspect-Based Fashion Recommendation With Attention Mechanism (open access)

Aspect-Based Fashion Recommendation With Attention Mechanism

Article proposes an aspect-based fashion recommendation model with attention mechanism (AFRAM) to predict customer ratings based on online reviews of fashion products. The experiment results demonstrate that AFRAM is more effective in customer rating predictions, as compared to several state-of-the-art fashion recommenders.
Date: August 3, 2020
Creator: Xu, Bugao
System: The UNT Digital Library
Assembly and Characterization of a Prototype Laser-Optical Firing System (open access)

Assembly and Characterization of a Prototype Laser-Optical Firing System

The design, assembly and characterization of the latest generation of a small, ruggedized laser-optical firing system will be discussed. This work builds upon earlier results in an effort to continue the development of robust fiber-coupled laseroptical firing systems.[1][2] This newest prototype strives to improve on earlier designs, while continuing to utilize many of the environmentally proven opto-mechanical sub-assemblies.[2][3] One area of improvement involves the implementation of a second optical safing and arming component. Several additional design improvements were also incorporated to address shortcomings uncovered during environmental testing.[4][5] These tests and the subsequent failure analysis were performed at the laser sub-system level. Four identical prototypes were assembled and characterized. The performance of the units were evaluated by comparing a number of parameters including laser output energy, slope efficiency, beam divergence, spatial intensity profile, fiber injection and splitter-coupler transmission efficiency. Other factors evaluated were the ease of alignment, repeatability of the alignment process and the fabrication of the fiberoptical cables. The experimentally obtained results will be compared and contrasted to the performance of earlier prototypes.
Date: August 3, 2009
Creator: Morelli, Gregg L
System: The UNT Digital Library
Book Review:Quantitative Paleozoology (open access)

Book Review:Quantitative Paleozoology

Book Review of "Quantitative Paleozoology" written by R. Lee Lyman.
Date: August 3, 2010
Creator: Wolverton, Steven J.
System: The UNT Digital Library
A Bottom-Up Approach to SUSY Analyses (open access)

A Bottom-Up Approach to SUSY Analyses

This paper proposes a new way to perform event generation and analysis in searches for new physics at the LHC. An abstract notation is used to describe the new particles on a level which better corresponds to detector resolution of LHC experiments. In this way the SUSY discovery space can be decomposed into a small number of eigenmodes each with only a few parameters, which allows to investigate the SUSY parameter space in a model-independent way. By focusing on the experimental observables for each process investigated the Bottom-Up Approach allows to systematically study the boarders of the experimental efficiencies and thus to extend the sensitivity for new physics.
Date: August 3, 2009
Creator: Horn, Claus
System: The UNT Digital Library
Cluster Analysis for CTBT Seismic Event Monitoring (open access)

Cluster Analysis for CTBT Seismic Event Monitoring

Mines at regional distances are expected to be continuing sources of small, ambiguous events which must be correctly identified as part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring process. Many of these events are small enough that they are only seen by one or two stations, so locating them by traditional methods maybe impossible or at best leads to poorly resolved parameters. To further complicate matters, these events have parametric characteristics (explosive sources, shallow depths) which make them difficult to identify as definite non-nuclear events using traditional discrimination methods. Fortunately, explosions from the same mines tend to have similar waveforms, making it possible to identify an unknown event by comparison with characteristic archived events that have been associated with specific mines. In this study we examine the use of hierarchical cluster methods to identify groups of similar events. These methods produce dendrograms, which are tree-like structures showing the relationships between entities. Hierarchical methods are well-suited to use for event clustering because they are well documented, easy to implement, computationally cheap enough to run multiple times for a given data set, and because these methods produce results which can be readily interpreted. To aid in determining the proper threshold value for …
Date: August 3, 1999
Creator: Carr, Dorthe B.; Young, Chris J.; Aster, Richard C. & Zhang, Xioabing
System: The UNT Digital Library
Code Optimization Techniques (open access)

Code Optimization Techniques

Computers transfer data in a number of different ways. Whether through a serial port, a parallel port, over a modem, over an ethernet cable, or internally from a hard disk to memory, some data will be lost. To compensate for that loss, numerous error detection and correction algorithms have been developed. One of the most common error correction codes is the Reed-Solomon code, which is a special subset of BCH (Bose-Chaudhuri-Hocquenghem) linear cyclic block codes. In the AURA project, an unmanned aircraft sends the data it collects back to earth so it can be analyzed during flight and possible flight modifications made. To counter possible data corruption during transmission, the data is encoded using a multi-block Reed-Solomon implementation with a possibly shortened final block. In order to maximize the amount of data transmitted, it was necessary to reduce the computation time of a Reed-Solomon encoding to three percent of the processor's time. To achieve such a reduction, many code optimization techniques were employed. This paper outlines the steps taken to reduce the processing time of a Reed-Solomon encoding and the insight into modern optimization techniques gained from the experience.
Date: August 3, 2000
Creator: MAGEE,GLEN I.
System: The UNT Digital Library
The Complete Genome Sequence of the Marine, Chemolithoautotrophic, Ammonia-Oxidizing Bacterium Nitrosococcus oceani ATCC19707 (open access)

The Complete Genome Sequence of the Marine, Chemolithoautotrophic, Ammonia-Oxidizing Bacterium Nitrosococcus oceani ATCC19707

The Gammaproteobacterium, Nitrosococcus oceani (ATCC 19707), is a Gram-negative obligate chemolithoautotroph capable of extracting energy and reducing power from the oxidation of ammonia to nitrite. Sequencing and annotation of the genome revealed a single circular chromosome (3,481,691 bp; 50.4% G+C) and a plasmid (40,420 bp) that contain 3052 and 41 candidate protein-encoding genes, respectively. The genes encoding proteins necessary for the function of known modes of lithotrophy and autotrophy were identified. In contrast to betaproteobacterial nitrifier genomes, the N. oceani genome contained two complete rrn operons. In contrast, only one copy of the genes needed to synthesize functional ammonia monooxygenase and hydroxylamine oxidoreductase, as well as the proteins that relay the extracted electrons to a terminal electron acceptor were identified. The N. oceani genome contained genes for 13 complete two-component systems. The genome also contained all the genes needed to reconstruct complete central pathways, the tricarboxylic acid cycle and the Embden-Meyerhof-Parnass and pentose phosphate pathways. The N. oceani genome contains the genes required to store and utilize energy from glycogen inclusion bodies and sucrose. Polyphosphate and pyrophosphate appear to be integrated in this bacterium's energy metabolism, stress tolerance and the ability to assimilate carbon via gluconeogenesis. One set of genes …
Date: August 3, 2006
Creator: Klotz, M. G.; Arp, D. J.; Chain, P. S.; El-Sheikh, A. F.; Hauser, L. J.; Hommes, N. G. et al.
System: The UNT Digital Library
Conceptual Design of the Drive Beam for a PWFA-LC (open access)

Conceptual Design of the Drive Beam for a PWFA-LC

Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for bunch with triangular shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective than the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed by the PWFA collaboration. Here we will describe the conceptual design and optimization of the drive beam, which includes the drive beam linac and distribution system. We apply experience of the CLIC drive beam design and demonstration in the CLIC Test Facility (CTF3) to this study. We discuss parameter optimization of the drive beam linac structure and evaluate the drive linac efficiency in terms of the drive beam distribution scheme and the klystron/modulator requirements.
Date: August 3, 2009
Creator: Pei, S.; Hogan, M. J.; Raubenheimer, T. O.; Seryi, A.; Braun, H. H.; Corsini, R. et al.
System: The UNT Digital Library
Connecting Reionization to the Local Universe (open access)

Connecting Reionization to the Local Universe

We present results of combined N-body and three-dimensional reionization calculations to determine the relationship between reionization history and local environment in a volume 1 Gpc h{sup -1} across and a resolution of about 1 Mpc. We resolve the formation of about 2 x 10{sup 6} halos of mass greater than {approx} 10{sup 12} M{sub {circle_dot}} at z = 0, allowing us to determine the relationship between halo mass and reionization epoch for galaxies and clusters. For our fiducial reionization model, in which reionization begins at z {approx} 15 and ends by z {approx} 6, we find a strong bias for cluster-size halos to be in the regions which reionized first, at redshifts 10 < z < 15. Consequently, material in clusters was reionized within relatively small regions, on the order of a few Mpc, implying that all clusters in our calculation were reionized by their own progenitors. Milky Way mass halos were on average reionized later and by larger regions, with a distribution most similar to the global one, indicating that low mass halos are nearly uncorrelated with reionization when only their mass is taken as a prior. On average, we find that most halos with mass less than 10{sup …
Date: August 3, 2009
Creator: Alvarez, Marcelo A.; Busha, Michael; Abel, Tom; Wechsler, Risa H. & /KIPAC, Menlo Park
System: The UNT Digital Library
Constraining the Scatter in the Mass-Richness Relation of maxBCG Clusters With Weak Lensing and X-ray Data (open access)

Constraining the Scatter in the Mass-Richness Relation of maxBCG Clusters With Weak Lensing and X-ray Data

We measure the logarithmic scatter in mass at fixed richness for clusters in the maxBCG cluster catalog, an optically selected cluster sample drawn from SDSS imaging data. Our measurement is achieved by demanding consistency between available weak lensing and X-ray measurements of the maxBCG clusters, and the X-ray luminosity-mass relation inferred from the 400d X-ray cluster survey, a flux limited X-ray cluster survey. We find {sigma}{sub lnM|N{sub 200}} = 0.45{sub -0.18}{sup +0.20} (95%CL) at N{sub 200} {approx} 40, where N{sub 200} is the number of red sequence galaxies in a cluster. As a byproduct of our analysis, we also obtain a constraint on the correlation coefficient between lnL{sub X} and lnM at fixed richness, which is best expressed as a lower limit, r{sub L,M|N} {ge} 0.85 (95% CL). This is the first observational constraint placed on a correlation coefficient involving two different cluster mass tracers. We use our results to produce a state of the art estimate of the halo mass function at z = 0.23 - the median redshift of the maxBCG cluster sample - and find that it is consistent with the WMAP5 cosmology. Both the mass function data and its covariance matrix are presented.
Date: August 3, 2009
Creator: Rozo, Eduardo; U., /Ohio State; Rykoff, Eli S.; /UC, Santa Barbara; Evrard, August; U., /Michigan et al.
System: The UNT Digital Library
Corrosion, Erosion andWear Behavior of Complex Concentrated Alloys: A Review (open access)

Corrosion, Erosion andWear Behavior of Complex Concentrated Alloys: A Review

This article presents a comprehensive view on corrosion, erosion, and wear behavior of complex concentrated alloys.
Date: August 3, 2018
Creator: Ayyagari, Aditya; Hasannaeimi, Vahid; Singh Grewal, Harpeet; Singh Arora, Harpreet & Mukherjee, Sundeep
System: The UNT Digital Library
Counting Statistics and Ion Interval Density in AMS (open access)

Counting Statistics and Ion Interval Density in AMS

Confidence in the precisions of AMS and decay measurements must be comparable for the application of the {sup 14}C calibration to age determinations using both technologies. We confirmed the random nature of the temporal distribution of {sup 14}C ions in an AMS spectrometer for a number of sample counting rates and properties of the sputtering process. The temporal distribution of ion counts was also measured to confirm the applicability of traditional counting statistics.
Date: August 3, 2004
Creator: Vogel, J S; Ognibene, T; Palmblad, M & Reimer, P
System: The UNT Digital Library
Damping Effect Studies for X-band Normal Conducting High Gradient Standing Wave Structures (open access)

Damping Effect Studies for X-band Normal Conducting High Gradient Standing Wave Structures

The Multi-TeV colliders should have the capability to accelerate low emittance beam with high rf efficiency, X-band normal conducting high gradient accelerating structure is one of the promising candidate. However, the long range transverse wake field which can cause beam emittance dilution is one of the critical issues. We examined effectiveness of dipole mode damping in three kinds of X-band, {pi}-mode standing wave structures at 11.424GHz with no detuning considered. They represent three damping schemes: damping with cylindrical iris slot, damping with choke cavity and damping with waveguide coupler. We try to reduce external Q factor below 20 in the first two dipole bands, which usually have very high (R{sub T}/Q){sub T}. The effect of damping on the acceleration mode is also discussed.
Date: August 3, 2009
Creator: Pei, S.; Li, Z.; Tantawi, S. G.; Dolgashev, V. A. & Wang, J.
System: The UNT Digital Library
Data Authentication Demonstration for Radionuclide Stations (open access)

Data Authentication Demonstration for Radionuclide Stations

Data authentication is required for certification of sensor stations in the International Monitoring System (IMS). Authentication capability has been previously demonstrated for continuous waveform stations (seismic and infrasound). This paper addresses data surety for the radionuclide stations in the IMS, in particular the Radionuclide Aerosol Sampler/Analyzer (RASA) system developed by Pacific Northwest National Laboratory (PNNL). Radionuclide stations communicate data by electronic mail using formats defined in IMS 1.0, Formats and Protocols for Messages. An open message authentication standard exists, called S/MIME (Secure/Multipurpose Internet Mail Extensions), which has been proposed for use with all IMS radionuclide station message communications. This standard specifies adding a digital signature and public key certificate as a MIME attachment to the e-mail message. It is advantageous because it allows authentication to be added to all IMS 1.0 messages in a standard format and is commercially supported in e-mail software. For command and control, the RASA system uses a networked Graphical User Interface (GUI) based upon Common Object Request Broker Architecture (CORBA) communications, which requires special authentication procedures. The authors have modified the RASA system to meet CTBTO authentication guidelines, using a FORTEZZA card for authentication functions. They demonstrated signing radionuclide data messages at the RASA, then …
Date: August 3, 1999
Creator: Harris, Mark; Herrington, Pres; Miley, Harry; Ellis, J. Edward; McKinnon, David & St. Pierre, Devon
System: The UNT Digital Library
Dependence of Gas-Phase Crotonaldehyde Hydrogenation Selectivity and Activity on the Size of Pt Nanoparticles (1.7-7.1 nm) Supported on SBA-15 (open access)

Dependence of Gas-Phase Crotonaldehyde Hydrogenation Selectivity and Activity on the Size of Pt Nanoparticles (1.7-7.1 nm) Supported on SBA-15

The selectivity and activity for the hydrogenation of crotonaldehyde to crotyl alcohol and butyraldehyde was studied over a series of Pt nanoparticles (diameter of 1.7, 2.9, 3.6, and 7.1 nm). The nanoparticles were synthesized by the reduction of chloroplatinic acid by alcohol in the presence of poly(vinylpyrrolidone) (PVP), followed by encapsulation into mesoporous SBA-15 silica. The rate of crotonaldehyde hydrogenation and selectivity towards crotyl alcohol both increase with increasing particle size. The selectivity towards crotyl alcohol increased from 13.7 % to 33.9 % (8 Torr crotonaldehyde, 160 Torr H{sub 2} and 353 K), while the turnover frequency increases from 2.1 x 10{sup -2} s{sup -1} to 4.8 x 10{sup -2} s{sup -1} with an increase in the particle size from 1.7 nm to 7.1 nm. The decarbonylation pathway to form propene and CO is enhanced over the higher proportion of coordinatively unsaturated sites on the smaller nanoparticles. The apparent activation energy remains constant ({approx} 16 kcal mol{sup -1} for the formation of butyraldehyde and {approx} 8 kcal mol{sup -1} for the formation of crotyl alcohol) as a function of particle size. In the presence of 130-260 mTorr CO, the reaction rate decreases for all products with a CO reaction order …
Date: August 3, 2008
Creator: Grass, Michael; Rioux, Robert & Somorjai, Gabor A.
System: The UNT Digital Library