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Faculty Publications

2007

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Macroh2a1 Knockdown Effects On The Peg3 Imprinted Domain, Jung Ha Choo, Jeong Do Kim, Joomyeong Kim Dec 2007

Macroh2a1 Knockdown Effects On The Peg3 Imprinted Domain, Jung Ha Choo, Jeong Do Kim, Joomyeong Kim

Faculty Publications

Background: MacroH2A1 is a histone variant that is closely associated with the repressed regions of chromosomes. A recent study revealed that this histone variant is highly enriched in the inactive alleles of Imprinting Control Regions (ICRs). Results: The current study investigates the potential roles of macroH2A1 in genomic imprinting by lowering the cellular levels of the macroH2A1 protein. RNAi-based macroH2A1 knockdown experiments in Neuro2A cells changed the expression levels of a subset of genes, including Peg3 and Usp29 of the Peg3 domain. The expression of these genes was down-regulated, rather than up-regulated, in response to reduced protein levels of the …

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Regional Body Composition In College-Aged Caucasians From Anthropometric Measures, Robert T. Davidson, Cameron B. Ritchie Dec 2007

Regional Body Composition In College-Aged Caucasians From Anthropometric Measures, Robert T. Davidson, Cameron B. Ritchie

Faculty Publications

Quantitating fat and lean tissue in isolated body regions may be helpful or required in obesity and health-outcomes research. However, current methods of regional body composition measurement require specialized, expensive equipment such as that used in computed tomography or dual energy x-ray absorptiometry (DEXA). Simple body size or circumference measurement relationships to body composition have been developed but are limited to whole-body applications. We investigated relationships between body size measurements and regional body composition. Methods Using DEXA technology we determined the fat and lean tissue composition for six regions of the body in predominantly Caucasian, college-aged men (n = 32) …

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Limits On Anomalous Triple Gauge Couplings In Pp̄ Collisions At S=1.96tev, T. Aaltonen, A. Abulencia, J. Adelman, T. Affolder, T. Akimoto, M. G. Albrow, S. Amerio, D. Amidei, A. Anastassov, K. Anikeev, A. Annovi, J. Antos, M. Aoki, G. Apollinari, T. Arisawa, A. Artikov, W. Ashmanskas, A. Attal, A. Aurisano, F. Azfar, P. Azzi-Bacchetta, P. Azzurri, N. Bacchetta, W. Badgett, A. Barbaro-Galtieri, V. E. Barnes, B. A. Barnett, S. Baroiant Dec 2007

Limits On Anomalous Triple Gauge Couplings In Pp̄ Collisions At S=1.96tev, T. Aaltonen, A. Abulencia, J. Adelman, T. Affolder, T. Akimoto, M. G. Albrow, S. Amerio, D. Amidei, A. Anastassov, K. Anikeev, A. Annovi, J. Antos, M. Aoki, G. Apollinari, T. Arisawa, A. Artikov, W. Ashmanskas, A. Attal, A. Aurisano, F. Azfar, P. Azzi-Bacchetta, P. Azzurri, N. Bacchetta, W. Badgett, A. Barbaro-Galtieri, V. E. Barnes, B. A. Barnett, S. Baroiant

Faculty Publications

We present a search for anomalous triple gauge couplings (ATGC) in WW and WZ boson production. The boson pairs are produced in pp̄ collisions at s=1.96TeV, and the data sample corresponds to 350pb-1 of integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. In this search one W decays to leptons, and the other boson (W or Z) decays hadronically. Combining with a previously published CDF measurement of Wγ boson production yields ATGC limits of -0.18<λ<0.17 and -0.46<Δκ<0.39 at the 95% confidence level, using a cutoff scale Λ=1.5TeV. © 2007 The American Physical Society.

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Digital Germany: Virtual Archives, Powerful Portals, Wise Wikis, Richard Hacken Dec 2007

Digital Germany: Virtual Archives, Powerful Portals, Wise Wikis, Richard Hacken

Faculty Publications

Presented in the Winter 2006-2007 issue of the Global Resources Newsletter, the German-North American Resources Partnership issue. Online portals and digital gateways into focused subject and area studies are both boons and blessings. For German Studies but even more extensively, for all disciplines relevant to the German-North American Resources Partnership this past year has seen explosive growth in the preparation, expansion, proofing, and proclamation of virtual libraries, scholarly digital projects, and multidisciplinary portals. German digital scholarship has reached a maturity that calls for the types of systematic registry and centralized access that are vital to researchers from Aachen to Zzyzx.

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Tidal Asymmetry And Residual Circulation Over Linear Sandbanks And Their Implication On Sediment Transport: A Process-Oriented Numerical Study, Rosario Sanay, George Voulgaris, John C. Warner Dec 2007

Tidal Asymmetry And Residual Circulation Over Linear Sandbanks And Their Implication On Sediment Transport: A Process-Oriented Numerical Study, Rosario Sanay, George Voulgaris, John C. Warner

Faculty Publications

A series of process-oriented numerical simulations is carried out in order to evaluate the relative role of locally generated residual flow and overtides on net sediment transport over linear sandbanks. The idealized bathymetry and forcing are similar to those present in the Norfolk Sandbanks, North Sea. The importance of bottom drag parameterization and bank orientation with respect to the ambient flow is examined in terms of residual flow and overtide generation, and subsequent sediment transport implications are discussed. The results show that although the magnitudes of residual flow and overtides are sensitive to bottom roughness parameterization and bank orientation, the …

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Arabian Sea Response To Monsoon Variations, Raghu Murtugudde, Richard Seager, Prasad Thoppil Dec 2007

Arabian Sea Response To Monsoon Variations, Raghu Murtugudde, Richard Seager, Prasad Thoppil

Faculty Publications

This study aims to quantify the impact of strong monsoons on the mixed layer heat budget in the Arabian Sea by contrasting forced ocean general circulation model simulations with composite strong and weak monsoon winds. Strong (weak) monsoons are defined as years with zonal component of the Somali Jet being greater (smaller) by more than a standard deviation of the long-term mean of the National Centers for Environmental Prediction reanalysis winds. Coastal upwelling is shown to be demonstrably stronger for strong monsoons leading to significant surface cooling, shallower thermoclines, and deeper mixed layers. A coupled ecosystem model shows that surface …

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Exchange Bias In Bulk Mn Rich Ni-Mn-Sn Heusler Alloys, Mahmud Khan, Igor Dubenko, Shane Stadler, Naushad Ali Dec 2007

Exchange Bias In Bulk Mn Rich Ni-Mn-Sn Heusler Alloys, Mahmud Khan, Igor Dubenko, Shane Stadler, Naushad Ali

Faculty Publications

An experimental study on the exchange bias properties of bulk polycrystalline Ni50 Mn50-x Snx Heusler alloys has been performed. Martensitic transformations have been observed in the alloys for some critical Sn concentrations. The alloys, while in their respective martensitic phases, are found to exhibit exchange bias effect. Shifts in hysteresis loops of up to 225 Oe were observed in the 50 kOe field cooled samples. The observed exchange bias behavior in Ni50 Mn50-x Snx is attributed to the coexistence of antiferromagnetic and ferromagnetic exchange interactions in the system. © 2007 American Institute of Physics.

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Concentration Of H, Si, Cl, K, Fe, And Th In The Low- And Mid-Latitude Regions Of Mars, W. V. Boynton, G. J. Taylor, Larry G. Evans, R. C. Reedy, Richard Starr, D. M. Janes, K. E. Kerry, D. M. Drake, K. J. Kim, R. M.S. Williams, M. K. Crombie, J. M. Dohm, A. E. Metzger, S. Karunatillake, J. M. Keller, H. E. Newsom, J. R. Arnold, J. Brückner, P. A.J. Englert, O. Gasnault, A. L. Sprague, I. Mitrofanov, Steven W. Squyres, Jacob I. Trombka, Lionel D'Uston, H. Wänke, D. K. Hamara Dec 2007

Concentration Of H, Si, Cl, K, Fe, And Th In The Low- And Mid-Latitude Regions Of Mars, W. V. Boynton, G. J. Taylor, Larry G. Evans, R. C. Reedy, Richard Starr, D. M. Janes, K. E. Kerry, D. M. Drake, K. J. Kim, R. M.S. Williams, M. K. Crombie, J. M. Dohm, A. E. Metzger, S. Karunatillake, J. M. Keller, H. E. Newsom, J. R. Arnold, J. Brückner, P. A.J. Englert, O. Gasnault, A. L. Sprague, I. Mitrofanov, Steven W. Squyres, Jacob I. Trombka, Lionel D'Uston, H. Wänke, D. K. Hamara

Faculty Publications

We report maps of the concentrations of H, Si, Cl, K, Fe, and Th as determined by the Gamma Ray Spectrometer (GRS) on board the 2001 Mars Odyssey Mission for ±∼45° latitudes. The procedures by which the spectra are processed to yield quantitative concentrations are described in detail. The concentrations of elements determined over the locations of the various Mars landers generally agree well with the lander values except for Fe, although the mean of the GRS Fe data agrees well with that of Martian meteorites. The water-equivalent concentration of hydrogen by mass varies from about 1.5% to 7.5% (by …

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Rising Minimum Daily Flows In Northern Eurasian Rivers: A Growing Influence Of Groundwater In The High‐Latitude Hydrologic Cycle, Laurence C. Smith, Tamlin M. Pavelsky, Glen M. Macdonald, Alexander I. Shiklomanov, Richard B. Lammers Dec 2007

Rising Minimum Daily Flows In Northern Eurasian Rivers: A Growing Influence Of Groundwater In The High‐Latitude Hydrologic Cycle, Laurence C. Smith, Tamlin M. Pavelsky, Glen M. Macdonald, Alexander I. Shiklomanov, Richard B. Lammers

Faculty Publications

A first analysis of new daily discharge data for 111 northern rivers from 1936–1999 and 1958–1989 finds an overall pattern of increasing minimum daily flows (or “low flows”) throughout Russia. These increases are generally more abundant than are increases in mean flow and appear to drive much of the overall rise in mean flow observed here and in previous studies. Minimum flow decreases have also occurred but are less abundant. The minimum flow increases are found in summer as well as winter and in nonpermafrost as well as permafrost terrain. No robust spatial contrasts are found between the European Russia, …

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Towards An Understanding Of Salient Neighborhood Boundaries: Adolescent Reports Of An Easy Walking Distance And Convenient Driving Distance, Natalie Colabianchi, Marsha Dowda, Karin A. Pfeiffer, Dwayne E. Porter, Maria João Ca Almeida, Russell R. Pate Dec 2007

Towards An Understanding Of Salient Neighborhood Boundaries: Adolescent Reports Of An Easy Walking Distance And Convenient Driving Distance, Natalie Colabianchi, Marsha Dowda, Karin A. Pfeiffer, Dwayne E. Porter, Maria João Ca Almeida, Russell R. Pate

Faculty Publications

Numerous studies have examined the association between the surrounding neighborhood environment and physical activity levels in adolescents. Many of these studies use a road network buffer or Euclidean distance buffer around an adolescent's home to represent the appropriate geographic area for study (i.e., neighborhood). However, little empirical research has examined the appropriate buffer size to use when defining this area and there is little consistency across published research as to the buffer size used. In this study, 909 12th grade adolescent girls of diverse racial and geographic backgrounds were asked to report their perceptions of an easy walking distance and …

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Towards An Understanding Of Salient Neighborhood Boundaries: Adolescent Reports Of An Easy Walking Distance And Convenient Driving Distance, Natalie Colabianchi, Marsha Dowda, Karin A. Pfeiffer, Dwayne E. Porter, Maria João C. A. Almeida, Russell R. Pate Dec 2007

Towards An Understanding Of Salient Neighborhood Boundaries: Adolescent Reports Of An Easy Walking Distance And Convenient Driving Distance, Natalie Colabianchi, Marsha Dowda, Karin A. Pfeiffer, Dwayne E. Porter, Maria João C. A. Almeida, Russell R. Pate

Faculty Publications

Numerous studies have examined the association between the surrounding neighborhood environment and physical activity levels in adolescents. Many of these studies use a road network buffer of Euclidean distance buffer around an adolescent's home to represent the appropriate geographic area for study (i.e., neighborhood). However, little empirical research has examined the appropriate buffer size to use when defining this area and there is little consistency across published research as to the buffer size used. In this study, 909 12th grade adolescent girls of diverse racial and geographic backgrounds were asked to report their perceptions of an easy walking distance …

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Search For Exclusive Γγ Production In Hadron-Hadron Collisions, T. Aaltonen, A. Abulencia, J. Adelman, T. Affolder, T. Akimoto, M. G. Albrow, S. Amerio, D. Amidei, A. Anastassov, K. Anikeev, A. Annovi, J. Antos, M. Aoki, G. Apollinari, T. Arisawa, A. Artikov, W. Ashmanskas, A. Attal, A. Aurisano, F. Azfar, P. Azzi-Bacchetta, P. Azzurri, N. Bacchetta, W. Badgett, A. Barbaro-Galtieri, V. E. Barnes, B. A. Barnett, S. Baroiant Dec 2007

Search For Exclusive Γγ Production In Hadron-Hadron Collisions, T. Aaltonen, A. Abulencia, J. Adelman, T. Affolder, T. Akimoto, M. G. Albrow, S. Amerio, D. Amidei, A. Anastassov, K. Anikeev, A. Annovi, J. Antos, M. Aoki, G. Apollinari, T. Arisawa, A. Artikov, W. Ashmanskas, A. Attal, A. Aurisano, F. Azfar, P. Azzi-Bacchetta, P. Azzurri, N. Bacchetta, W. Badgett, A. Barbaro-Galtieri, V. E. Barnes, B. A. Barnett, S. Baroiant

Faculty Publications

We have searched for exclusive γγ production in proton-antiproton collisions at s=1.96TeV, using 532pb-1 of integrated luminosity taken by the run II Collider Detector at Fermilab. The event signature requires two electromagnetic showers, each with transverse energy ET>5GeV and pseudorapidity |η|<1.0, with no other particles detected in the event. Three candidate events are observed. We discuss the consistency of the three events with γγ, π0π0, or ηη production. The probability that other processes fluctuate to 3 events is 1.7×10-4. An upper limit on the cross section of pp̄→p+γγ+p̄ production is set at 410 fb with 95% confidence level. © 2007 The American Physical Society.

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A Regional Modeling Study Of The Entraining Mediterranean Outflow, Xiaobiao Xu, E. P. Chassignet, J. F. Price, T. M. Özgökmen, H. Peters Dec 2007

A Regional Modeling Study Of The Entraining Mediterranean Outflow, Xiaobiao Xu, E. P. Chassignet, J. F. Price, T. M. Özgökmen, H. Peters

Faculty Publications

[1] We have evaluated a regional-scale simulation of the Mediterranean outflow by comparison with field data obtained in the 1988 Gulf of Cadiz Expedition. Our ocean model is based upon the Hybrid Coordinate Ocean Model (HYCOM) and includes the Richardson number-dependent entrainment parameterization of Xu et al. (2006). Given realistic topography and sufficient resolution, the model reproduces naturally the major, observed features of the Mediterranean outflow in the Gulf of Cadiz: the downstream evolution of temperature, salinity, and velocity profiles, the mean path and the spreading of the outflow plume, and most importantly, the localized, strong entrainment that has been …

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Mobile Dna Elements In Primate And Human Evolution, Jinchuan Xing, David J. Witherspoon, David A. Ray, Mark A. Batzer, Lynn B. Jorde Dec 2007

Mobile Dna Elements In Primate And Human Evolution, Jinchuan Xing, David J. Witherspoon, David A. Ray, Mark A. Batzer, Lynn B. Jorde

Faculty Publications

Roughly 50% of the primate genome consists of mobile, repetitive DNA sequences such as Alu and LINE1 elements. The causes and evolutionary consequences of mobile element insertion, which have received considerable attention during the past decade, are reviewed in this article. Because of their unique mutational mechanisms, these elements are highly useful for answering phylogenetic questions. We demonstrate how they have been used to help resolve a number of questions in primate phylogeny, including the human-chimpanzee- gorilla trichotomy and New World primate phylogeny. Alu and LINE1 element insertion polymorphisms have also been analyzed in human populations to test hypotheses about …

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Multijet Production At Low XBj In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi Dec 2007

Multijet Production At Low XBj In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi

Faculty Publications

Inclusive dijet and trijet production in deep inelastic ep scattering has been measured for 10 < Q2 < 100 GeV2 and low Bjorken x, 10-4 < xBj < 10-2. The data were taken at the HERA ep collider with centre-of-mass energy sqrt(s) = 318 GeV using the ZEUS detector and correspond to an integrated luminosity of 82 pb-1. Jets were identified in the hadronic centre-of-mass (HCM) frame using the kT cluster algorithm in the longitudinally invariant inclusive mode. Measurements of dijet and trijet differential cross sections are presented as functions of Q2, xBj, jet transverse energy, and jet pseudorapidity. As a further examination of low-xBj dynamics, multi-differential cross sections as functions of the jet correlations in transverse momenta, azimuthal angles, and pseudorapidity are also presented. Calculations at O (αs3) generally describe the trijet data well and improve the description of the dijet data compared to the calculation at O (αs2). © 2007 Elsevier B.V. All rights reserved.

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Measurement Of (Anti)Deuteron And (Anti)Proton Production In Dis At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi Dec 2007

Measurement Of (Anti)Deuteron And (Anti)Proton Production In Dis At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi

Faculty Publications

The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300-318 GeV using an integrated luminosity of 120 pb-1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3 < pT / M < 0.7. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements. © 2007 Elsevier B.V. All rights reserved.

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Attosecond Control Of Ionization By Wave-Packet Interference, P. Johnsson, J. Mauritsson, T. Remetter, A. L'Huillier, K. J. Schafer Dec 2007

Attosecond Control Of Ionization By Wave-Packet Interference, P. Johnsson, J. Mauritsson, T. Remetter, A. L'Huillier, K. J. Schafer

Faculty Publications

A train of attosecond pulses, synchronized to an infrared (IR) laser field, is used to create a series of electron wave packets (EWPs) that are below the ionization threshold in. helium. The ionization probability is found to strongly oscillate with the delay between the IR and attosecond fields twice per IR laser cycle. Calculations that reproduce the experimental results demonstrate that this ionization control results from interference between transiently bound EWPs created by different pulses in the train. In this way, we are able to observe, for the first time, attosecond wave-packet interference in a strongly driven atomic system. © …

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The Effect Of Contact Length On Adhesion Between Carbon Nanotubes On Silicon Dioxide, Robert C. Davis, Kaylee Mcelroy, Aaron R. Hopkins Dec 2007

The Effect Of Contact Length On Adhesion Between Carbon Nanotubes On Silicon Dioxide, Robert C. Davis, Kaylee Mcelroy, Aaron R. Hopkins

Faculty Publications

The force of adhesion was measured for single walled carbon nanotubes grown over lithographically defined silicon dioxide trenches. We varied contact lengths between the nanotubes and silicon dioxide from 230 to 850 nm. Suspended nanotubes were pushed vertically into the trenches with an atomic force microscope tip, causing them to slip along the surface. Previous work done at shorter contact lengths found that tension was constant with contact length [J. D. Whittaker et al., Nano Lett. 6, 953 (2006)]. This study finds that when the nanotube contact length approaches 1 µm, the tension at which nanotubes slip begins to increase …

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Recoil Velocities From Equal-Mass Binary Black-Hole Mergers: A Systematic Investigation Of Spin-Orbit Aligned Configurations, Denis Pollney, Christian Reisswig, Luciano Rezzolla, Béla Szilágyi, Marcus Ansorg, Barrett Deris, Peter Diener, Ernst Nils Dorband, Michael Koppitz, Alessandro Nagar, Erik Schnetter Dec 2007

Recoil Velocities From Equal-Mass Binary Black-Hole Mergers: A Systematic Investigation Of Spin-Orbit Aligned Configurations, Denis Pollney, Christian Reisswig, Luciano Rezzolla, Béla Szilágyi, Marcus Ansorg, Barrett Deris, Peter Diener, Ernst Nils Dorband, Michael Koppitz, Alessandro Nagar, Erik Schnetter

Faculty Publications

Binary black-hole systems with spins aligned with the orbital angular momentum are of special interest, as studies indicate that this configuration is preferred in nature due to non-vacuum environmental interactions, as well as post-Newtonian (PN) spin-orbit couplings. If the spins of the two bodies differ, there can be a prominent beaming of the gravitational radiation during the late plunge, causing a recoil of the final merged black hole. In this paper we perform an accurate and systematic study of recoil velocities from a sequence of equal-mass black holes whose spins are aligned with the orbital angular momentum, and whose individual …

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). Size Dependency Of The Elastic Modulus Of Zno Nanowires: Surface Stress Effect, Guofeng Wang, Xiaodong Li Dec 2007

). Size Dependency Of The Elastic Modulus Of Zno Nanowires: Surface Stress Effect, Guofeng Wang, Xiaodong Li

Faculty Publications

Relation between the elastic modulus and the diameter (D) of ZnOnanowires was elucidated using a model with the calculated ZnOsurface stresses as input. We predict for ZnOnanowires due to surface stress effect: (1) when D>20nm, the elastic modulus would be lower than the bulk modulus and decrease with the decreasing diameter, (2) when 20nm>D>2nm, the nanowires with a longer length and a wurtzite crystal structure could be mechanically unstable, and (3) when D<2nm, the elastic modulus would be higher than that of the bulk value and increase with a decrease in nanowire diameter.

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Moments And Commutators Of Probability Measures, Luigi Accardi, Hui Hsiung Kuo, Aurel Stan Dec 2007

Moments And Commutators Of Probability Measures, Luigi Accardi, Hui Hsiung Kuo, Aurel Stan

Faculty Publications

Let a0, a- and a+ be the preservation, annihilation, and creation operators of a probability measure μ on ℝd, respectively. The operators a0 and [a -, a+] are proven to uniquely determine the moments of μ. We discuss the question: "What conditions must two families of operators satisfy, in order to ensure the existence of a probability measure, having finite moments of any order, so that, its associated preservation operators and commutators between the annihilation and creation operators are the given families of operators?" For the case d = 1, a satisfactory answer to this question is obtained as a …

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Fluxes Of Iron And Manganese Across The Sediment-Water Interface Under Various Redox Conditions, Svetlana V. Pakhomova, Per O.J. Hall, Mikhail Yu Kononets, Alexander G. Rozanov, Anders Tengberg, Andrei V. Vershinin Dec 2007

Fluxes Of Iron And Manganese Across The Sediment-Water Interface Under Various Redox Conditions, Svetlana V. Pakhomova, Per O.J. Hall, Mikhail Yu Kononets, Alexander G. Rozanov, Anders Tengberg, Andrei V. Vershinin

Faculty Publications

Fluxes of dissolved forms of iron and manganese across the sediment-water interface were studied in situ in the Gulf of Finland and the Vistula Lagoon (Baltic Sea), and in the Golubaya Bay (Black Sea) from 2001 to 2005. Fluxes were measured using chamber incubations, and sediment cores were collected and sliced to assess the porewater and solid phase metal distribution at different depths. Measured and calculated benthic fluxes of manganese and iron were directed out of sediment for all sites and were found to vary between 70-4450 and 5-1000 μmole m- 2 day- 1 for manganese and iron, respectively. The …

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The Need For Proper Vouchering In Phylogenetic Studies Of Birds, A. Townsend Peterson, Robert G. Moyle, Árpád S. Nyári, Mark B. Robbins, Robb T. Brumfield, J. V. Remsen Dec 2007

The Need For Proper Vouchering In Phylogenetic Studies Of Birds, A. Townsend Peterson, Robert G. Moyle, Árpád S. Nyári, Mark B. Robbins, Robb T. Brumfield, J. V. Remsen

Faculty Publications

No abstract provided.

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From Population Sources To Sieves: The Matrix Alters Host-Parasitoid Source-Sink Structure, James T. Cronin Dec 2007

From Population Sources To Sieves: The Matrix Alters Host-Parasitoid Source-Sink Structure, James T. Cronin

Faculty Publications

Field experiments that examine the impact of immigration, emigration, or landscape structure (e.g., the composition of the matrix) on the source-sink dynamics of fragmented populations are scarce. Here, planthoppers (Prokelisia crocea) and egg parasitoids (Anagrus columbi) were released among host-plant patches that varied in structural (caged, isolated, or in a network of other patches) and functional (mudflat matrix that impedes dispersal vs. brome-grass matrix that facilitates dispersal) connectivity. Planthoppers and parasitoids on caged patches exhibited density-dependent growth rates, achieved high equilibrium densities, and rarely went extinct. Therefore, experimental cordgrass patches were classified as population sources. Because access to immigrants did …

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Shared Parasitoids In A Metacommunity: Indirect Interactions Inhibit Herbivore Membership In Local Communities, James T. Cronin Dec 2007

Shared Parasitoids In A Metacommunity: Indirect Interactions Inhibit Herbivore Membership In Local Communities, James T. Cronin

Faculty Publications

The interaction between species, mediated by a shared natural enemy (i.e., apparent competition), has been the subject of much theoretical and empirical investigation. However, we lack field experiments that assess the importance of apparent competition to metacommunity structure. Here, I conducted a series of field experiments to test whether apparent competition, mediated by shared egg parasitoids (Anagrus nigriventris and A. columbi), occurs between two abundant planthopper species (Delphacodes scolochloa and Prokelisia crocea) of the North American Great Plains. The two planthoppers feed on different plant species within prairie potholes (wet depressions) and, thus, do not interact directly. At the scale …

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Density Gradient Enrichment Of Escherichia Coli Conditional Msba Mutants, William T. Doerrler Dec 2007

Density Gradient Enrichment Of Escherichia Coli Conditional Msba Mutants, William T. Doerrler

Faculty Publications

Insight into the mechanism of lipid transport to the outer membrane of gram-negative bacteria has been hampered by the lack of an effective genetic screen for defective mutants. This work demonstrates an enrichment of conditional mutants defective in lipopolysaccharide export by Ludox density gradient centrifugation and selection for detergent resistance. New temperature-sensitive mutants with lipid export defects were isolated with single missense mutations in msbA. The results demonstrate the power of this approach for the study of lipid export in Escherichia coli. Copyright © 2007, American Society for Microbiology. All Rights Reserved.

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Elachista Saccharella (Lepidoptera: Elachistidae), A Leafminer Infesting Sugarcane In Louisiana, W. H. White, T. E. Reagan, C. Carlton, W. Akbar, J. M. Beuzelin Dec 2007

Elachista Saccharella (Lepidoptera: Elachistidae), A Leafminer Infesting Sugarcane In Louisiana, W. H. White, T. E. Reagan, C. Carlton, W. Akbar, J. M. Beuzelin

Faculty Publications

The leafminer, Elachista saccharella (Busck) (Lepidoptera: Elachistidae) was found in Louisiana on 12 Jul 2006 and documented as a new distribution record for Louisiana. The leafminer was found in 17 of 20 sugarcane producing parishes surveyed. Although distributed generally throughout the sugarcane growing region, only 11% of the stalks sampled (n = 1600) were infested and 69% of the samples collected were parasitized. The lesions made by the leafminer constituted only 3% of the total leaf area, and were usually detected on older leaves deep within the canopy. For these reasons, it does not appear that E. saccharella will be …

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Monitoring The Low-Energy Gamma-Ray Sky Using Earth Occultation With Glast Gbm, G. L. Case, C. A. Wilson-Hodge, M. L. Cherry, R. M. Kippen, J. C. Ling, R. G. Radocinski, W. A. Wheaton Dec 2007

Monitoring The Low-Energy Gamma-Ray Sky Using Earth Occultation With Glast Gbm, G. L. Case, C. A. Wilson-Hodge, M. L. Cherry, R. M. Kippen, J. C. Ling, R. G. Radocinski, W. A. Wheaton

Faculty Publications

Long term all-sky monitoring of the 20 keV - 2 MeV gamma-ray sky using the Earth occultation technique was demonstrated by the BATSE instrument on the Compton Gamma Ray Observatory. The principles and techniques used for the development of an end-to-end earth occultation data analysis system for BATSE can be extended to the GLAST Burst Monitor (GBM), resulting in multiband light curves and time-resolved spectra in the energy range 8 keV to above 1 MeV for known gamma-ray sources and transient outbursts, as well as the discovery of new sources of gamma-ray emission. In this paper we describe the application …

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Superexponential Distortion Of Subgroups Of Cat(-1) Groups, Josh Barnard, Noel Brady, Pallavi Dani Dec 2007

Superexponential Distortion Of Subgroups Of Cat(-1) Groups, Josh Barnard, Noel Brady, Pallavi Dani

Faculty Publications

We construct 2 -dimensional CAT(1) groups which contain free subgroups with arbitrary iterated exponential distortion, and with distortion higher than any iterated exponential. © 2007 Mathematical Sciences Publishers.

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Signature-Tagged Mutagenesis Of Edwardsiella Ictaluri Identifies Virulence-Related Genes, Including A Salmonella Pathogenicity Island 2 Class Of Type Iii Secretion Systems, Ronald L. Thune, Denise H. Fernandez, Jennifer L. Benoit, Maria Kelly-Smith, Matthew L. Rogge, Natha J. Booth, Christie A. Landry, Rachel A. Bologna Dec 2007

Signature-Tagged Mutagenesis Of Edwardsiella Ictaluri Identifies Virulence-Related Genes, Including A Salmonella Pathogenicity Island 2 Class Of Type Iii Secretion Systems, Ronald L. Thune, Denise H. Fernandez, Jennifer L. Benoit, Maria Kelly-Smith, Matthew L. Rogge, Natha J. Booth, Christie A. Landry, Rachel A. Bologna

Faculty Publications

Edwardsieila ictaluri is the leading cause of mortality in channel catfish culture, but little is known about its pathogenesis. The use of signature-tagged mutagenesis in a waterborne infection model resulted in the identification of 50 mutants that were unable to infect/survive in catfish. Nineteen had minitransposon insertions in miscellaneous genes in the chromosome, 10 were in genes that matched to hypothetical proteins, and 13 were in genes that had no significant matches in the NCBI databases. Eight insertions were in genes encoding proteins associated with virulence in other pathogens, including three in genes involved in lipopolysaccharide biosynthesis, three in genes …

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