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The Greensheet (Houston, Tex.), Vol. 43, No. 26, Ed. 1 Tuesday, February 14, 2012 (open access)

The Greensheet (Houston, Tex.), Vol. 43, No. 26, Ed. 1 Tuesday, February 14, 2012

Free weekly newspaper that includes business and classified advertising.
Date: February 14, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Houston, Tex.), Vol. 43, No. 25, Ed. 1 Tuesday, February 14, 2012 (open access)

The Greensheet (Houston, Tex.), Vol. 43, No. 25, Ed. 1 Tuesday, February 14, 2012

Free weekly newspaper that includes business and classified advertising.
Date: February 14, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
NARAC Modeling During the Response to the Fukushima Dai-ichi Nuclear Power Plant Emergency (open access)

NARAC Modeling During the Response to the Fukushima Dai-ichi Nuclear Power Plant Emergency

This paper summarizes the activities of the National Atmospheric Release Advisory Center (NARAC) during the Fukushima Dai-ichi nuclear power plant crisis. NARAC provided a wide range of products and analyses as part of its support including: (1) Daily Japanese weather forecasts and hypothetical release (generic source term) dispersion predictions to provide situational awareness and inform planning for U.S. measurement data collection and field operations; (2) Estimates of potential dose in Japan for hypothetical scenarios developed by the Nuclear Regulatory Commission (NRC) to inform federal government considerations of possible actions that might be needed to protect U.S. citizens in Japan; (3) Estimates of possible plume arrival times and dose for U.S. locations; and (4) Plume model refinement and source estimation based on meteorological analyses and available field data. The Department of Energy/National Nuclear Security Administration (DOE/NNSA) deployed personnel to Japan and stood up 'home team' assets across the DOE complex to aid in assessing the consequences of the releases from the Fukushima Dai-ichi Nuclear Power Plant. The DOE Nuclear Incident Team (NIT) coordinated response activities, while DOE personnel provided predictive modeling, air and ground monitoring, sample collection, laboratory analysis, and data assessment and interpretation. DOE deployed the Aerial Measuring System (AMS), …
Date: February 14, 2012
Creator: Sugiyama, G.; Nasstrom, J. S.; Probanz, B.; Foster, K. T.; Simpson, M.; Vogt, P. et al.
Object Type: Article
System: The UNT Digital Library
Air-Cooled Stack Freeze Tolerance Freeze Failure Modes and Freeze Tolerance Strategies for GenDriveTM Material Handling Application Systems and Stacks Final Scientific Report (open access)

Air-Cooled Stack Freeze Tolerance Freeze Failure Modes and Freeze Tolerance Strategies for GenDriveTM Material Handling Application Systems and Stacks Final Scientific Report

Air-cooled stack technology offers the potential for a simpler system architecture (versus liquid-cooled) for applications below 4 kilowatts. The combined cooling and cathode air allows for a reduction in part count and hence a lower cost solution. However, efficient heat rejection challenges escalate as power and ambient temperature increase. For applications in ambient temperatures below freezing, the air-cooled approach has additional challenges associated with not overcooling the fuel cell stack. The focus of this project was freeze tolerance while maintaining all other stack and system requirements. Through this project, Plug Power advanced the state of the art in technology for air-cooled PEM fuel cell stacks and related GenDrive material handling application fuel cell systems. This was accomplished through a collaborative work plan to improve freeze tolerance and mitigate freeze-thaw effect failure modes within innovative material handling equipment fuel cell systems designed for use in freezer forklift applications. Freeze tolerance remains an area where additional research and understanding can help fuel cells to become commercially viable. This project evaluated both stack level and system level solutions to improve fuel cell stack freeze tolerance. At this time, the most cost effective solutions are at the system level. The freeze mitigation strategies developed …
Date: February 14, 2012
Creator: Hancock, David, W.
Object Type: Report
System: The UNT Digital Library
SuperB Progress Report for Physics (open access)

SuperB Progress Report for Physics

SuperB is a high luminosity e{sup +}e{sup -} collider that will be able to indirectly probe new physics at energy scales far beyond the reach of any man made accelerator planned or in existence. Just as detailed understanding of the Standard Model of particle physics was developed from stringent constraints imposed by flavour changing processes between quarks, the detailed structure of any new physics is severely constrained by flavour processes. In order to elucidate this structure it is necessary to perform a number of complementary studies of a set of golden channels. With these measurements in hand, the pattern of deviations from the Standard Model behavior can be used as a test of the structure of new physics. If new physics is found at the LHC, then the many golden measurements from SuperB will help decode the subtle nature of the new physics. However if no new particles are found at the LHC, SuperB will be able to search for new physics at energy scales up to 10-100 TeV. In either scenario, flavour physics measurements that can be made at SuperB play a pivotal role in understanding the nature of physics beyond the Standard Model. Examples for using the interplay …
Date: February 14, 2012
Creator: O'Leary, B.; Matias, J.; Ramon, M.; Pous, E.; De Fazio, F.; Palano, A. et al.
Object Type: Report
System: The UNT Digital Library
The DEEP2 Galaxy Redshift Survey: The Voronoi-Delaunay Method Catalog of Galaxy Groups (open access)

The DEEP2 Galaxy Redshift Survey: The Voronoi-Delaunay Method Catalog of Galaxy Groups

We use the first 25% of the DEEP2 Galaxy Redshift Survey spectroscopic data to identify groups and clusters of galaxies in redshift space. The data set contains 8370 galaxies with confirmed redshifts in the range 0.7 {<=} z {<=} 1.4, over one square degree on the sky. Groups are identified using an algorithm (the Voronoi-Delaunay Method) that has been shown to accurately reproduce the statistics of groups in simulated DEEP2-like samples. We optimize this algorithm for the DEEP2 survey by applying it to realistic mock galaxy catalogs and assessing the results using a stringent set of criteria for measuring group-finding success, which we develop and describe in detail here. We find in particular that the group-finder can successfully identify {approx}78% of real groups and that {approx}79% of the galaxies that are true members of groups can be identified as such. Conversely, we estimate that {approx}55% of the groups we find can be definitively identified with real groups and that {approx}46% of the galaxies we place into groups are interloper field galaxies. Most importantly, we find that it is possible to measure the distribution of groups in redshift and velocity dispersion, n({sigma}, z), to an accuracy limited by cosmic variance, for …
Date: February 14, 2012
Creator: Gerke, Brian F.; Newman, Jeffrey A.; Davis, Marc; Marinoni, Christian; Yan, Renbin; Coil, Alison L. et al.
Object Type: Article
System: The UNT Digital Library
Branching Fraction Measurements of the Color-Suppressed Decays B0bar to D(*)0 pi0, D(*)0 eta, D(*)0 omega, and D(*)0 eta_prime and Measurement of the Polarization in the Decay B0bar to D*0 omega (open access)

Branching Fraction Measurements of the Color-Suppressed Decays B0bar to D(*)0 pi0, D(*)0 eta, D(*)0 omega, and D(*)0 eta_prime and Measurement of the Polarization in the Decay B0bar to D*0 omega

We report updated branching fraction measurements of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}', and D*{sup 0}{eta}'. We measure the branching fractions (x10{sup -4}): {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}) = 2.69 {+-} 0.09 {+-} 0.13, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{pi}{sup 0}) = 3.05 {+-} 0.14 {+-} 0.28, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}) = 2.53 {+-} 0.09 {+-} 0.11, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}) = 2.69 {+-} 0.14 {+-} 0.23, {Beta}({bar B}{sup 0} {yields} D{sup 0}{omega}) = 2.57 {+-} 0.11 {+-} 0.14, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{omega}) = 4.55 {+-} 0.24 {+-} 0.39, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}') = 1.48 {+-} 0.13 {+-} 0.07, and {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}') = 1.49 {+-} 0.22 {+-} 0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D*{sup 0}{omega}, f{sub L} = (66.5 {+-} 4.7 {+-} 1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance, with …
Date: February 14, 2012
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
Object Type: Article
System: The UNT Digital Library
Ab-initio description of quasiparticle band structures and optical near-edge absorption of transparent conducting oxides (open access)

Ab-initio description of quasiparticle band structures and optical near-edge absorption of transparent conducting oxides

None
Date: February 14, 2012
Creator: Schleife, A & Bechstedt, F
Object Type: Article
System: The UNT Digital Library
Integrated genome-based studies of Shewanella ecophysiology (open access)

Integrated genome-based studies of Shewanella ecophysiology

This project was a component of the Shewanella Federation and, as such, contributed to the overall goal of applying the genomic tools to better understand eco-physiology and speciation of respiratory-versatile members of Shewanella genus. Our role at Boston University was to perform bioreactor and high throughput gene expression microarrays, and combine dynamic flux balance modeling with experimentally obtained transcriptional and gene expression datasets from different growth conditions. In the first part of project, we designed the S. oneidensis microarray probes for Affymetrix Inc. (based in California), then we identified the pathways of carbon utilization in the metal-reducing marine bacterium Shewanella oneidensis MR-1, using our newly designed high-density oligonucleotide Affymetrix microarray on Shewanella cells grown with various carbon sources. Next, using a combination of experimental and computational approaches, we built algorithm and methods to integrate the transcriptional and metabolic regulatory networks of S. oneidensis. Specifically, we combined mRNA microarray and metabolite measurements with statistical inference and dynamic flux balance analysis (dFBA) to study the transcriptional response of S. oneidensis MR-1 as it passes through exponential, stationary, and transition phases. By measuring time-dependent mRNA expression levels during batch growth of S. oneidensis MR-1 under two radically different nutrient compositions (minimal lactate and …
Date: February 14, 2012
Creator: Daniel, Segre & Qasim, Beg
Object Type: Report
System: The UNT Digital Library
A Natural Language for AdS/CFT Correlators (open access)

A Natural Language for AdS/CFT Correlators

We provide dramatic evidence that 'Mellin space' is the natural home for correlation functions in CFTs with weakly coupled bulk duals. In Mellin space, CFT correlators have poles corresponding to an OPE decomposition into 'left' and 'right' sub-correlators, in direct analogy with the factorization channels of scattering amplitudes. In the regime where these correlators can be computed by tree level Witten diagrams in AdS, we derive an explicit formula for the residues of Mellin amplitudes at the corresponding factorization poles, and we use the conformal Casimir to show that these amplitudes obey algebraic finite difference equations. By analyzing the recursive structure of our factorization formula we obtain simple diagrammatic rules for the construction of Mellin amplitudes corresponding to tree-level Witten diagrams in any bulk scalar theory. We prove the diagrammatic rules using our finite difference equations. Finally, we show that our factorization formula and our diagrammatic rules morph into the flat space S-Matrix of the bulk theory, reproducing the usual Feynman rules, when we take the flat space limit of AdS/CFT. Throughout we emphasize a deep analogy with the properties of flat space scattering amplitudes in momentum space, which suggests that the Mellin amplitude may provide a holographic definition of …
Date: February 14, 2012
Creator: Fitzpatrick, A. Liam; Kaplan, Jared; Penedones, Joao; Raju, Suvrat & van Rees, Balt C.
Object Type: Article
System: The UNT Digital Library
Scattering States in AdS/CFT (open access)

Scattering States in AdS/CFT

We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.
Date: February 14, 2012
Creator: Fitzpatrick, A.Liam; U., /Boston & Kaplan, Jared
Object Type: Report
System: The UNT Digital Library
Evaluation of Representative Smart Grid Investment Grant Project Technologies: Thermal Energy Storage (open access)

Evaluation of Representative Smart Grid Investment Grant Project Technologies: Thermal Energy Storage

This document is one of a series of reports estimating the benefits of deploying technologies similar to those implemented on the Smart Grid Investment Grant (SGIG) projects. Four technical reports cover the various types of technologies deployed in the SGIG projects, distribution automation, demand response, energy storage, and renewables integration. A fifth report in the series examines the benefits of deploying these technologies on a national level. This technical report examines the impacts of energy storage technologies deployed in the SGIG projects.
Date: February 14, 2012
Creator: Tuffner, Francis K. & Bonebrake, Christopher A.
Object Type: Report
System: The UNT Digital Library
SuperB Progress Report: Detector (open access)

SuperB Progress Report: Detector

This report describes the present status of the detector design for SuperB. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.
Date: February 14, 2012
Creator: Grauges, E.; /Barcelona U., ECM; Donvito, G.; Spinoso, V.; /INFN, Bari /Bari U.; Manghisoni, M. et al.
Object Type: Report
System: The UNT Digital Library
Evaluation of Representative Smart Grid Investment Project Technologies: Demand Response (open access)

Evaluation of Representative Smart Grid Investment Project Technologies: Demand Response

This document is one of a series of reports estimating the benefits of deploying technologies similar to those implemented on the Smart Grid Investment Grant (SGIG) projects. Four technical reports cover the various types of technologies deployed in the SGIG projects, distribution automation, demand response, energy storage, and renewables integration. A fifth report in the series examines the benefits of deploying these technologies on a national level. This technical report examines the impacts of a limited number of demand response technologies and implementations deployed in the SGIG projects.
Date: February 14, 2012
Creator: Fuller, Jason C.; Prakash Kumar, Nirupama & Bonebrake, Christopher A.
Object Type: Report
System: The UNT Digital Library
Three-dimensional modeling and analysis of a high energy density Kelvin-Helmholtz experiment (open access)

Three-dimensional modeling and analysis of a high energy density Kelvin-Helmholtz experiment

None
Date: February 14, 2012
Creator: Raman, K. S.; Hurricane, O. A.; Park, H. S.; Remington, B. A.; Robey, H. & Smalyuk, V. A.
Object Type: Article
System: The UNT Digital Library
Magnetorotational Turbulence Transports Angular Momentum in Stratified Disks with Low Magnetic Prandtl Number but Magnetic Reynolds Number above a Critical Value (open access)

Magnetorotational Turbulence Transports Angular Momentum in Stratified Disks with Low Magnetic Prandtl Number but Magnetic Reynolds Number above a Critical Value

The magnetorotational instability (MRI) may dominate outward transport of angular momentum in accretion disks, allowing material to fall onto the central object. Previous work has established that the MRI can drive a mean-field dynamo, possibly leading to a self-sustaining accretion system. Recently, however, simulations of the scaling of the angular momentum transport parameter {alpha}{sub SS} with the magnetic Prandtl number Pm have cast doubt on the ability of the MRI to transport astrophysically relevant amounts of angular momentum in real disk systems. Here, we use simulations including explicit physical viscosity and resistivity to show that when vertical stratification is included, mean field dynamo action operates, driving the system to a configuration in which the magnetic field is not fully helical. This relaxes the constraints on the generated field provided by magnetic helicity conservation, allowing the generation of a mean field on timescales independent of the resistivity. Our models demonstrate the existence of a critical magnetic Reynolds number Rm{sub crit}, below which transport becomes strongly Pm-dependent and chaotic, but above which the transport is steady and Pm-independent. Prior simulations showing Pm-dependence had Rm < Rm{sub crit}. We conjecture that this steady regime is possible because the mean field dynamo is not …
Date: February 14, 2012
Creator: Oishi, Jeffrey S.; /KIPAC, Menlo Park; Low, Mordecai-Mark Mac & Hist., /Amer. Museum Natural
Object Type: Article
System: The UNT Digital Library
Composite Octet Searches with Jet Substructure (open access)

Composite Octet Searches with Jet Substructure

Many new physics models with strongly interacting sectors predict a mass hierarchy between the lightest vector meson and the lightest pseudoscalar mesons. We examine the power of jet substructure tools to extend the 7 TeV LHC sensitivity to these new states for the case of QCD octet mesons, considering both two gluon and two b-jet decay modes for the pseudoscalar mesons. We develop both a simple dijet search using only the jet mass and a more sophisticated jet substructure analysis, both of which can discover the composite octets in a dijet-like signature. The reach depends on the mass hierarchy between the vector and pseudoscalar mesons. We find that for the pseudoscalar-to-vector meson mass ratio below approximately 0.2 the simple jet mass analysis provides the best discovery limit; for a ratio between 0.2 and the QCD-like value of 0.3, the sophisticated jet substructure analysis has the best discovery potential; for a ratio above approximately 0.3, the standard four-jet analysis is more suitable.
Date: February 14, 2012
Creator: Bai, Yang & Shelton, Jessie
Object Type: Article
System: The UNT Digital Library
SuperB Progress Report for Accelerator (open access)

SuperB Progress Report for Accelerator

This report details the progress made in by the SuperB Project in the area of the Collider since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008. With this document we propose a new electron positron colliding beam accelerator to be built in Italy to study flavor physics in the B-meson system at an energy of 10 GeV in the center-of-mass. This facility is called a high luminosity B-factory with a project name 'SuperB'. This project builds on a long history of successful e+e- colliders built around the world, as illustrated in Figure 1.1. The key advances in the design of this accelerator come from recent successes at the DAFNE collider at INFN in Frascati, Italy, at PEP-II at SLAC in California, USA, and at KEKB at KEK in Tsukuba Japan, and from new concepts in beam manipulation at the interaction region (IP) called 'crab waist'. This new collider comprises of two colliding beam rings, one at 4.2 GeV and one at 6.7 GeV, a common interaction region, a new injection system at full beam energies, and one of the two beams longitudinally polarized at the IP. Most …
Date: February 14, 2012
Creator: Biagini, M. E.; Boni, R.; Boscolo, M.; Buonomo, B.; Demma, T.; Drago, A. et al.
Object Type: Report
System: The UNT Digital Library
Rains County Leader (Emory, Tex.), Vol. 125, No. 35, Ed. 1 Tuesday, February 14, 2012 (open access)

Rains County Leader (Emory, Tex.), Vol. 125, No. 35, Ed. 1 Tuesday, February 14, 2012

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: February 14, 2012
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Low-Dimensional Water on Ru(0001)Model System for X-ray Absorption Spectroscopy Studies of Liquid Water (open access)

Low-Dimensional Water on Ru(0001)Model System for X-ray Absorption Spectroscopy Studies of Liquid Water

We present an x-ray absorption spectroscopy results for fully broken to a complete H-bond network of water molecules on Ru(0001) by varying the morphology from isolated water molecules via two-dimensional clusters to a fully covered monolayer as probed by scanning tunneling microscopy. The sensitivity of x-ray absorption to the symmetry of H-bonding is further elucidated for the amino (-NH{sub 2}) group in glycine adsorbed on Cu(110) where the E-vector is parallel either to the NH donating an H-bond or to the non-H-bonded NH. The results give further evidence for the interpretation of the various spectral features of liquid water and for the general applicability of x-ray absorption spectroscopy to analyze H-bonded systems.
Date: February 14, 2012
Creator: Nordlund, D.
Object Type: Article
System: The UNT Digital Library
North Texas Daily (Denton, Tex.), Vol. 99, No. 17, Ed. 1 Tuesday, February 14, 2012 (open access)

North Texas Daily (Denton, Tex.), Vol. 99, No. 17, Ed. 1 Tuesday, February 14, 2012

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state, and campus news along with advertising.
Date: February 14, 2012
Creator: Gorman, Sean
Object Type: Newspaper
System: The Portal to Texas History
Sweetwater Reporter (Sweetwater, Tex.), Vol. 114, No. 024, Ed. 1 Tuesday, February 14, 2012 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 114, No. 024, Ed. 1 Tuesday, February 14, 2012

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: February 14, 2012
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Understanding Energy Code Acceptance within the Alaska Building Community (open access)

Understanding Energy Code Acceptance within the Alaska Building Community

This document presents the technical assistance provided to the Alaska Home Financing Corporation on behalf of PNNL regarding the assessment of attitudes toward energy codes within the building community in Alaska. It includes a summary of the existing situation and specific assistance requested by AHFC, the results of a questionnaire designed for builders surveyed in a suburban area of Anchorage, interviews with a lender, a building official, and a research specialist, and recommendations for future action by AHFC.
Date: February 14, 2012
Creator: Mapes, Terry S.
Object Type: Report
System: The UNT Digital Library
$A^t_{FB}$ Meets LHC (open access)

$A^t_{FB}$ Meets LHC

The recent Tevatron measurement of the forward-backward asymmetry of the top quark shows an intriguing discrepancy with Standard Model expectations, particularly at large t{bar t} invariant masses. Measurements of this quantity are subtle at the LHC, due to its pp initial state, however, one can define a forward-central-charge asymmetry which captures the physics. We study the capability of the LHC to measure this asymmetry and find that within the SM a measurement at the 5{sigma} level is possible with roughly 60 fb{sup -1} at {radical}s = 14 TeV. If nature realizes a model which enhances the asymmetry (as is necessary to explain the Tevatron measurements), a significant difference from zero can be observed much earlier, perhaps even during early LHC running at {radical}s = 7 TeV. We further explore the capabilities of the 7 TeV LHC to discover resonances or contact interactions which modify the t{bar t} invariant mass distribution using recent boosted top tagging techniques. We find that TeV-scale color octet resonances can be discovered, even with small coupling strengths and that contact interactions can be probed at scales exceeding 6 TeV. Overall, the LHC has good potential to clarify the situation with regards to the Tevatron forward-backward measurement.
Date: February 14, 2012
Creator: Hewett, JoAnne L.; /SLAC; Shelton, Jessie; U., /Yale; Spannowsky, Michael; U., /Oregon et al.
Object Type: Article
System: The UNT Digital Library