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Numerical Modeling Of A Gravity Wave Packet Ducted By The Thermal Structure Of The Atmosphere, Yonghui Yu, Michael P. Hickey Ph.D. Jun 2007

Numerical Modeling Of A Gravity Wave Packet Ducted By The Thermal Structure Of The Atmosphere, Yonghui Yu, Michael P. Hickey Ph.D.

Publications

A time-dependent and fully nonlinear numerical model is employed to solve the Navier-Stokes equations in two spatial dimensions and to describe the propagation of a Gaussian gravity wave packet generated in the troposphere. A Fourier spectral analysis is used to analyze the frequency power spectra of the wave packet, which propagates through and dwells within several thermal ducting regions. The frequency power spectra of the wave packet are derived at several discrete altitudes, which allow us to determine the evolution of the packet. This spectral analysis also clearly reveals the existence of a stratospheric duct, a mesospheric and lower thermospheric …

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Internet Enabled Remote Driving Of A Combat Hybrid Electric Power System For Duty Cycle Measurement, Jarrett Goodell, Marc Compere, Wilford Smith, Mark Brudnak, Mike Pozolo, Et Al. Jun 2007

Internet Enabled Remote Driving Of A Combat Hybrid Electric Power System For Duty Cycle Measurement, Jarrett Goodell, Marc Compere, Wilford Smith, Mark Brudnak, Mike Pozolo, Et Al.

Publications

This paper describes a human-in-the-loop motion-based simulator interfaced to hybrid-electric power system hardware, both of which were used to measure the duty cycle of a combat vehicle in a virtual simulation environment. The project discussed is a greatly expanded follow-on to the experiment published in [1,7]. This paper is written in the context of [1,7] and therefore highlights the enhancements. The most prominent of these enhancements is the integration (in real-time) of the Power & Energy System Integration Lab (P&E SIL) with a motion base simulator by means of a “long haul” connection over the Internet (a geographical distance of …

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The New Class Of Dusty Daz White Dwarfs, Ted Von Hippel, Et Al. Jun 2007

The New Class Of Dusty Daz White Dwarfs, Ted Von Hippel, Et Al.

Publications

Our mid-infrared survey of 124 white dwarfs with the Spitzer Space Telescope and the IRAC imager has revealed an infrared excess associated with the white dwarf WD 2115-560 naturally explained by circumstellar dust. This object is the fourth white dwarf observed to have circumstellar dust. All four are DAZ white dwarfs, i.e., they have both photospheric Balmer lines and photospheric metal lines. We discuss these four objects as a class, which we abbreviate "DAZd," where the "d" stands for "dust." Using an optically thick, geometrically thin disk model analogous to Saturn's rings, we find that the inner disk edges are …

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Translocation Of Swamp Rabbits In Southern Illinois, Angela M. Watland, Eric M. Schauber, Alan Woolf Jun 2007

Translocation Of Swamp Rabbits In Southern Illinois, Angela M. Watland, Eric M. Schauber, Alan Woolf

Publications

Habitat of Sylvilagus aquaticus (swamp rabbits) in Illinois has been reduced and fragmented due to human land use. Translocation may enable swamp rabbits to colonize isolated habitat patches. We live-trapped and translocated 9 male and 8 female swamp rabbits to unoccupied habitat in southern Illinois in January and February 2004. Eight of 17 translocated rabbits died within 7 days after release. However, mortality rates appeared to drop rapidly over time after release. Predators killed at least 10 of 14 rabbits that died. For conserving swamp rabbits, translocation success is limited by poor live-trapping success and high levels of post-release predation. …

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Space Use And Survival Of White-Tailed Deer In An Exurban Landscape, Daniel J. Storm, Clayton K. Nielsen, Eric M. Schauber, Alan Woolf Jun 2007

Space Use And Survival Of White-Tailed Deer In An Exurban Landscape, Daniel J. Storm, Clayton K. Nielsen, Eric M. Schauber, Alan Woolf

Publications

Exurban development is nonmetropolitan, residential development characterized by a human population density and average property size intermediate between suburban and rural areas. Although growth in exurban areas is outpacing that of urban, suburban, or rural landscapes, studies of deer (Odocoileus spp.) ecology in exurban areas are nonexistent. During 2003–2005, we studied space use (i.e., seasonal home-range and core-area size and habitat use relative to human dwellings) and survival of 43 female white-tailed deer (O. virginianus) in an exurban setting near Carbondale, Illinois. Deer had larger home ranges than most suburban deer populations and generally smaller home ranges …

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Lp 133-373: A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, T. R. Vaccaro, M. Rudkin, A. Kawka, S. Vennes, Terry D. Oswalt, Et Al. Jun 2007

Lp 133-373: A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, T. R. Vaccaro, M. Rudkin, A. Kawka, S. Vennes, Terry D. Oswalt, Et Al.

Publications

We report the discovery of the partially eclipsing binary LP 133-373. Nearly identical eclipses along with observed photometric colors and spectroscopy indicate that it is a pair of chromospherically active dM4 stars in a circular 1.6 day orbit. Light and velocity curve modeling to our differential photometry and velocity data show that each star has a mass and radius of 0:340 ± 0:014 MꙨ and 0:33 ± 0:02 RꙨ. The binary is itself part of a common proper motion pair with LP 133-374, a cool DC or possible DA white dwarf with a mass of 0.49Y0.82 M …

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Optical Absorption, Depolarization, And Scatter Of Epitaxial Single-Crystal Chemical-Vapor-Deposited Diamond At 1.064 Μm, Giorgio Turri, Ying Chen, Michael Bass Jun 2007

Optical Absorption, Depolarization, And Scatter Of Epitaxial Single-Crystal Chemical-Vapor-Deposited Diamond At 1.064 Μm, Giorgio Turri, Ying Chen, Michael Bass

Publications

No abstract provided.

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Lp133-373 A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, T. R. Vaccaro, T. D. Oswalt, M. Rudkin, Adela Kawka, Stephane Vennes, Et Al. Jun 2007

Lp133-373 A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, T. R. Vaccaro, T. D. Oswalt, M. Rudkin, Adela Kawka, Stephane Vennes, Et Al.

Publications

We report the discovery of the partially eclipsing binary LP 133-373. Nearly identical eclipses along with observed photometric colors and spectroscopy indicate that it is a pair of chromospherically active dM4 stars in a circular 1.6 day orbit. Light and velocity curve modeling to our differential photometry and velocity data show that each star has a mass and radius of 0.340 ± 0.014 M☉ and 0.33 ± 0.02 R☉. The binary is itself part of a common proper motion pair with LP 133-374, a cool DC or possible DA white dwarf with a mass of 0.49-0.82 M☉, …

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Discovery Of Photospheric Calcium Line-Strength Variations In The Dazd White Dwarf G29-38, Ted Von Hippel, Susan E. Thompson May 2007

Discovery Of Photospheric Calcium Line-Strength Variations In The Dazd White Dwarf G29-38, Ted Von Hippel, Susan E. Thompson

Publications

Metals in the photospheres of white dwarfs with Teff between 12,000 and 25,000 K should gravitationally settle out of these atmospheres in 1 ̶ 2 weeks. Temporal variations in the line strengths of these metals could provide a direct measurement of episodic metal accretion. Using archival VLT and Keck spectroscopy, we find evidence that the DAZd white dwarf G29-38 shows significant changes in its Ca П K line strength. At the two best-observed epochs, we find that the Ca line equivalent width (EW) = 165 ̶ 4 mǺ (in 1996.885) and 280 ± 8 mǺ (in 1999.653), which is …

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Magnetic Behavior Of Manganese-Doped Znse Quantum Dots, Amit D. Lad, Ch. Rajesh, Mahmud Khan, Naushad Ali, I. K. Gopalakrishnan, S. K. Kulshreshtha, Shailaja Mahamuni May 2007

Magnetic Behavior Of Manganese-Doped Znse Quantum Dots, Amit D. Lad, Ch. Rajesh, Mahmud Khan, Naushad Ali, I. K. Gopalakrishnan, S. K. Kulshreshtha, Shailaja Mahamuni

Publications

Magnetic properties of manganese-doped ZnSe quantum dots with the size of approximately 3.6 nm are investigated. The amount of Mn in the ZnSe quantum dots has been varied from 0.10% to 1.33%. The doping level in the quantum dots is much less than that used in the precursor. The co-ordination of Mn in the ZnSe lattice has been determined by electron paramagnetic resonance (EPR). Two different hyperfine couplings 67.3×10−4 and 60.9×10−4 cm−1 observed in the EPR spectrum imply that Mn atoms occupy two distinct sites; one uncoordinated (near the surface) and other having a cubic symmetric environment …

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An Algorithm For Implementing Gibbs Sampling For 2pno Irt Models (Fortran), Yanyan Sheng, Todd C. Headrick May 2007

An Algorithm For Implementing Gibbs Sampling For 2pno Irt Models (Fortran), Yanyan Sheng, Todd C. Headrick

Publications

A Fortran 77 subroutine is provided for implementing the Gibbs sampling procedure to a normal ogive IRT model for binary item response data with the choice of uniform and normal prior distributions for item parameters. The subroutine requires the user to have access to the IMSL library.

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Magnetocaloric Properties Of Fe And Ge Doped Ni2mn1−Xcuxga, Mahmud Khan, Shane Stadler, Naushad Ali May 2007

Magnetocaloric Properties Of Fe And Ge Doped Ni2mn1−Xcuxga, Mahmud Khan, Shane Stadler, Naushad Ali

Publications

The magnetocaloric properties of Fe and Ge doped Ni2Mn0.75Cu0.25Ga Heusler alloys have been investigated. Using Ni2Mn0.75Cu0.25Ga as the parent material, the Fe doped system (Ni2Mn1−x(Cu–Fe)xGa) and a Ge doped system (Ni2Mn1−xCuxGa1−xGex) were studied. The manipulation of the Mn–Cu subsystem with Fe doping results in a decrease of the first order magnetostructural transition temperature, whereas the substitution of Ge for the Mn–Cu–Ga subsystems results in an increase of the magnetostructural …

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Testing A Mahalanobis Distance Model Of Black Bear Habitat Use In The Ouachita Mountains Of Oklahoma, Eric C. Hellgren, Sara L. Bales, Mark S. Gregory, David M. Leslie, Jr., Joseph D. Clark May 2007

Testing A Mahalanobis Distance Model Of Black Bear Habitat Use In The Ouachita Mountains Of Oklahoma, Eric C. Hellgren, Sara L. Bales, Mark S. Gregory, David M. Leslie, Jr., Joseph D. Clark

Publications

Regional wildlife–habitat models are commonly developed but rarely tested with truly independent data. We tested a published habitat model for black bears (Ursus americanus) with new data collected in a different site in the same ecological region (i.e., Ouachita Mountains of Arkansas and Oklahoma, USA). We used a Mahalanobis distance model developed from relocations of black bears in Arkansas to produce a map layer of Mahalanobis distances on a study area in neighboring Oklahoma. We tested this modeled map layer with relocations of black bears on the Oklahoma area. The distributions of relocations of female black bears were …

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Spatial Selection And Inheritance: Applying Evolutionary Concepts To Population Dynamics In Heterogeneous Space., Eric M Schauber, Brett J Goodwin, Clive G Jones, Richard S Ostfeld May 2007

Spatial Selection And Inheritance: Applying Evolutionary Concepts To Population Dynamics In Heterogeneous Space., Eric M Schauber, Brett J Goodwin, Clive G Jones, Richard S Ostfeld

Publications

Organisms in highly suitable sites generally produce more offspring, and offspring can inherit this suitability by not dispersing far. This combination of spatial selection and spatial inheritance acts to bias the distribution of organisms toward suitable sites and thereby increase mean fitness (i.e., per capita population increase). Thus, population growth rates in heterogeneous space change over time by a process conceptually analogous to evolution by natural selection, opening avenues for theoretical cross-pollination between evolutionary biology and ecology. We operationally define spatial inheritance and spatial selective differential and then combine these two factors in a modification of the breeder's equation, derived …

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Uaa Student Showcase Journal: Recognizing Excellence (2007), N/A N/A Apr 2007

Uaa Student Showcase Journal: Recognizing Excellence (2007), N/A N/A

Publications

No abstract provided.

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Warm Gas In The Inner Disks Around Young Intermediate-Mass Stars, Sean D. Brittain, Theodore Simon, Joan R. Najita, Terrence W. Rettig Apr 2007

Warm Gas In The Inner Disks Around Young Intermediate-Mass Stars, Sean D. Brittain, Theodore Simon, Joan R. Najita, Terrence W. Rettig

Publications

The characterization of gas in the inner disks around young stars is of particular interest because of its connection to planet formation. In order to study the gas in inner disks, we have obtained high-resolution K- and M-band spectroscopy of 14 intermediate-mass young stars. In sources that have optically thick inner disks, i.e., E(K-L)>1, our detection rate of the rovibrational CO transitions is 100%, and the gas is thermally excited. Of the five sources that do not have optically thick inner disks, we only detect the rovibrational CO transitions from HD 141569. In this case, we show that the …

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A Lean Modeling Protocol For Evaluating Green Project Delivery, Leidy E. Klotz, Michael Horman, Mark Bodenschatz Apr 2007

A Lean Modeling Protocol For Evaluating Green Project Delivery, Leidy E. Klotz, Michael Horman, Mark Bodenschatz

Publications

The first vital step to leaning an operation is to model or map the processes used to deliver value in that operation. This allows the requisite understanding of where waste and non value-adding activity exists, and provides the foundation for improvement. Current protocols for modeling operations present the basic tenets for lean mapping, but tend to be based in manufacturing language, and are not easily adapted to capital facilities projects. “Green” or “sustainable” capital projects delivered using current project delivery systems seem to be laden with hidden waste. These projects tend to be more challenging to deliver due increased levels …

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Infrared High-Resolution Spectroscopy Of Post-Agb Circumstellar Disks. I. Hr 4049: The Winnowing Flow Observed?, Kenneth H. Hinkle, Sean D. Brittain, David L. Lambert Apr 2007

Infrared High-Resolution Spectroscopy Of Post-Agb Circumstellar Disks. I. Hr 4049: The Winnowing Flow Observed?, Kenneth H. Hinkle, Sean D. Brittain, David L. Lambert

Publications

High-resolution infrared spectroscopy in the 2.3-4.6 micron region is reported for the peculiar A supergiant, single-lined spectroscopic binary HR 4049. Lines from the CO fundamental and first overtone, OH fundamental, and several H2O vibration-rotation transitions have been observed in the near-infrared spectrum. The spectrum of HR 4049 appears principally in emission through the 3 and 4.6 micron region and in absorption in the 2 micron region. The 4.6 micron spectrum shows a rich 'forest' of emission lines. All the spectral lines observed in the 2.3-4.6 micron spectrum are shown to be circumbinary in origin. The presence of OH and H2O …

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Associating Larvae And Adults Of Chinese Hydropsychidae Caddiflies (Insecta:Trichoptera) Using Dna Sequences, Xin Zhou, Karl M. Kjer, John C. Morse Apr 2007

Associating Larvae And Adults Of Chinese Hydropsychidae Caddiflies (Insecta:Trichoptera) Using Dna Sequences, Xin Zhou, Karl M. Kjer, John C. Morse

Publications

The utility of hydropsychid (Trichoptera:Hydropsychidae) caddisfly larvae for freshwater biomonitoring has been demonstrated, but the major impediment to its implementation has been the lack of species-level larval descriptions and illustrations. A rapid and reliable molecular protocol that also uses morphology is proposed because conventional approaches to associating undescribed larvae with adults have been slow and problematic. Male adults were identified before DNA sequence analyses were used. These identifications established morphospecies boundaries that were mapped on phylograms constructed from 2 independent gene fragments: mitochondrial cytochrome c oxidase subunit I (COI) and large subunit (28S) nuclear ribosomal DNA expansion fragment D2 (D2). …

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Possible Identification Of A Metal-Rich Old Moving Group: High-Resolution Spectroscopy Of Candidate Members, Abigail R. Daane, Jeremy R. King, Simon C. Schuler Apr 2007

Possible Identification Of A Metal-Rich Old Moving Group: High-Resolution Spectroscopy Of Candidate Members, Abigail R. Daane, Jeremy R. King, Simon C. Schuler

Publications

Using new high-resolution spectroscopic observations from both the McDonald Observatory 2.7 m and Kitt Peak National Observatory 4 m telescopes, we observed four candidate members of the Ursa Major moving group previously suggested to instead belong to a significantly older kinematic assemblage. The Fe abundances we measure strongly suggest that these stars are not UMa members but form a more metal-rich group of stars (+0.10 ≤ [Fe/H] ≤ +0.18) with an age near 3 Gyr. Our [Ca/H] determinations corroborate this result. The apparent similarities in metallicity and previously discovered UVW space motions lend credence to prior suggestions that these stars …

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Entitles: Booker T. Washington's Signs Of Play, Susanna Ashton Apr 2007

Entitles: Booker T. Washington's Signs Of Play, Susanna Ashton

Publications

No abstract provided.

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Warm Hcn, C2h2, And Co In The Disk Of Gv Tau, E L. Gibb, K A. Vanbrunt, Sean D. Brittain, T W. Rettig Apr 2007

Warm Hcn, C2h2, And Co In The Disk Of Gv Tau, E L. Gibb, K A. Vanbrunt, Sean D. Brittain, T W. Rettig

Publications

We present the first high-resolution, ground-based observations of HCN and C2H2 toward the T Tauri binary star system GV Tau. We detected strong absorption due to HCN nu3 and weak C2H2 [nu3 and nu2+(nu4+nu5)0+] absorption toward the primary (GV Tau S) but not the infrared companion. We also report CO column densities and rotational temperatures, and present abundances relative to CO of HCN/CO~0.6% and C2H/CO~1.2% and an upper limit for CH4/CO

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From The Reference Desk To River City: A Bibliography Of The Writings Of Robert C. Berring, Frank G. Houdek Apr 2007

From The Reference Desk To River City: A Bibliography Of The Writings Of Robert C. Berring, Frank G. Houdek

Publications

Professor Houdek documents the prolific and eclectic body of work of Robert C. Berring, including the books, chapters, articles, and assorted other materials he has written to date on subjects ranging from law libraries and legal information to legal research instruction and Chinese law and history.

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Numerical Computing And Graphics For The Power Method Transformation Using Mathematica, Todd C. Headrick, Yanyan Sheng, Flaviu-Adrian Hodis Apr 2007

Numerical Computing And Graphics For The Power Method Transformation Using Mathematica, Todd C. Headrick, Yanyan Sheng, Flaviu-Adrian Hodis

Publications

This paper provides the requisite information and description of software that perform numerical computations and graphics for the power method polynomial transformation. The software developed is written in the Mathematica 5.2 package PowerMethod.m and is associated with fifth-order polynomials that are used for simulating univariate and multivariate non-normal distributions. The package is flexible enough to allow a user the choice to model theoretical pdfs, empirical data, or a user's own selected distribution(s). The primary functions perform the following (a) compute standardized cumulants and polynomial coefficients, (b) ensure that polynomial transformations yield valid pdfs, and (c) graph power method pdfs and …

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Shark Porn: Film Genre, Reception Studies, And Chris Kentis' Open Water, Walter C. Metz Apr 2007

Shark Porn: Film Genre, Reception Studies, And Chris Kentis' Open Water, Walter C. Metz

Publications

This essay develops the notion of "anti-genre" as a reception frame for thinking about the relationship between pornography and the horror film, Open Water (Chris Kentis, 2003).

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The Case For Teaching Network Protocols To Computer Forensics Examiners, Gary C. Kessler, Matt Fasulo Apr 2007

The Case For Teaching Network Protocols To Computer Forensics Examiners, Gary C. Kessler, Matt Fasulo

Publications

"Most computer forensics experts are well-versed in basic computer hardware technology, operating systems, common software applications, and computer forensics tools. And while many have rudimentary knowledge about the Internet and simple network-lookup tools, they are not trained in the analysis of network communication protocols and the use of packet sniffers. This paper describes digital forensics applications for network analysis and includes four case studies."

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Derivation And Application Of A Conserved Orbital Energy For The Inverted Pendulum Bipedal Walking Model, Jerry E. Pratt, Sergey V. Drakunov Apr 2007

Derivation And Application Of A Conserved Orbital Energy For The Inverted Pendulum Bipedal Walking Model, Jerry E. Pratt, Sergey V. Drakunov

Publications

We present an analysis of a point mass, point foot, planar inverted pendulum model for bipedal walking. Using this model, we derive expressions for a conserved quantity, the “Orbital Energy”, given a smooth Center of Mass trajectory. Given a closed form Center of Mass Trajectory, the equation for the Orbital Energy is a closed form expression except for an integral term, which we show to be the first moment of area under the Center of Mass path. Hence, given a Center of Mass trajectory, it is straightforward and computationally simple to compute phase portraits for the system. In fact, for …

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Doppler Ducting Of Short-Period Gravity Waves By Midaltitude Tidal Wind Structure, Jonathan B. Snively, Victor P. Pasko, Michael J. Taylor, Wayne K. Hocking Mar 2007

Doppler Ducting Of Short-Period Gravity Waves By Midaltitude Tidal Wind Structure, Jonathan B. Snively, Victor P. Pasko, Michael J. Taylor, Wayne K. Hocking

Publications

Multiwavelength airglow image data depicting a short-period (∼4.9 min) atmospheric gravity wave characterized by a sharp leading front have been analyzed together with synoptic meteor radar wind data recorded simultaneously from Bear Lake Observatory, Utah (41.6°N, 111.6°W). The wind data suggest the presence of a semidiurnal tide with horizontal winds peaking at around 60 m/s along the SSE direction of motion (170° from north) of this short-period wave. It was found that the gravity wave was most probably ducted because of the Doppler shift imposed by this wind structure. A marked 180° phase shift was observed between the near-infrared OH …

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New Techniques To Determine Ages Of Open Clusters Using White Dwarfs, E. J. Jeffery, Ted Von Hippel, Et Al. Mar 2007

New Techniques To Determine Ages Of Open Clusters Using White Dwarfs, E. J. Jeffery, Ted Von Hippel, Et Al.

Publications

Currently there are two main techniques for independently determining the ages of stellar populations: main-sequence evolution theory (via cluster isochrones) and white dwarf cooling theory. Open clusters provide the ideal environment for the calibration of these two clocks. Because current techniques to derive cluster ages from white dwarfs are observationally challenging, we discuss the feasibility of determining white dwarf ages from the brighter white dwarfs alone. This would eliminate the requirement of observing the coolest (i.e., faintest) white dwarfs. We discuss our method for testing this new idea, as well as the required photometric precision and prior constraints on metallicity, …

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Poisson-Boltzmann Calculations Of Nonspecific Salt Effects On Protein-Protein Binding Free Energies, Claudia Bertonati, Barry Honig, Emil Alexov Mar 2007

Poisson-Boltzmann Calculations Of Nonspecific Salt Effects On Protein-Protein Binding Free Energies, Claudia Bertonati, Barry Honig, Emil Alexov

Publications

The salt dependence of the binding free energy of five protein-protein hetero-dimers and two homo-dimers/tetramers was calculated from numerical solutions to the Poisson-Boltzmann equation. Overall, the agreement with experimental values is very good. In all cases except one involving the highly charged lactoglobulin homo-dimer, increasing the salt concentration is found both experimentally and theoretically to decrease the binding affinity. To clarify the source of salt effects, the salt-dependent free energy of binding is partitioned into screening terms and to self-energy terms that involve the interaction of the charge distribution of a monomer with its own ion atmosphere. In six of …

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