Digital Commons Network^™

Accumulation Of A Polyisoprene-Linked Amino Sugar In Polymyxin-Resistant Salmonella Typhimurium And Escherichia Coli: Structural Characterization And Transfer To Lipid A In The Periplasm, M. Stephen Trent, Anthony A. Ribeiro, William T. Doerrler, Shanhua Lin, Robert J. Cotter, Christian R.H. Raetz

Faculty Publications

Polymyxin-resistant mutants of Escherichia coli and Salmonella typhimurium accumulate a novel minor lipid that can donate 4-amino-4-deoxy-L-arabinose units (L-Ara4N) to lipid A. We now report the purification of this lipid from a pss- pmrAC mutant of E. coli and assign its structure as undecaprenyl phosphate-α-L-Ara4N. Approximately 0.2 mg of homogeneous material was isolated from an 8-liter culture by solvent extraction, followed by chromatography on DEAE-cellulose, C18 reverse phase resin, and silicic acid. Matrix-assisted laser desorption ionization/time of flight mass spectrometry in the negative mode yielded a single species [M - H]- at m/z 977.5, consistent with undecaprenyl phosphate-α-L-Ara4N (Mr = …

Annotated Bibliography Of Research In The Teaching Of English, Deborah Brown, Judith Kalman, Macrina Gómez, Gert Rijlaarsdam, Anne D'Antonio Stinson, Melissa E. Whiting

Faculty Publications

Twice a year, in the May and November issues, RTE publishes a selected bibliography of recent research in literacy education, Most of the studies appeared during the six-month period preceding the compilation of the bibliography (January through June, 2001 for the present bibliography), but studies that appeared earlier are occasionally included. The listing is selective;; we make no attempt to include all research and research-related articles that appeared in the period tinder review Comments on the bibliography and suggestions about items for inclusion may be directed to the bibliography editors. We encourage you to send your suggestions to [email protected], [email protected], …

Ca4Iro6, Ca3Mgiro6 And Ca3Zniro6, Matthew J. Davis, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

Single crystals of tetracalcium iridium hexaoxide, Ca₄IrO₆, tricalcium magnesium iridium hexaoxide, Ca₃MgIrO₆, and tricalcium zinc iridium hexaoxide, Ca₃ZnIrO₆, were prepared via high-temperature flux growth and structurally characterized by single-crystal X-ray diffraction. The three compounds are isostructural and adopt the K₄CdCl₆ structure type, comprised of chains of alternating face-shared [CaO₆], [MgO₆] or [ZnO₆] trigonal prisms and [IrO₆] octahedra, surrounded by columns of Ca²⁺ ions.

Formula: Ca₄IrO₆, Ca_3.34Mg_0.66IrO₆ and …

High-Pressure Elastic Properties Of Major Materials Of Earth's Mantle From First Principles, Bijaya B. Karki, Lars Stixrude, Renata M. Wentzcovitch

Faculty Publications

The elasticity of materials is important for our understanding of processes ranging from brittle failure, to flexure, to the propagation of elastic waves. Seismologically revealed structure of the Earth's mantle, including the radial (one-dimensional) profile, lateral heterogeneity, and anisotropy are determined largely by the elasticity of the materials that make up this region. Despite its importance to geophysics, our knowledge of the elasticity of potentially relevant mineral phases at conditions typical of the Earth's mantle is still limited: Measuring the elastic constants at elevated pressure-temperature conditions in the laboratory remains a major challenge. Over the past several years, another approach …

Concentration Gradient, Diffusion, And Flow Through Open Porous Medium Near Percolation Threshold Via Computer Simulations, Ras B. Pandey, J.F. Gettrust, D. Stauffer

Faculty Publications

The interacting lattice gas model is used to simulate fluid flow through an open percolating porous medium with the fluid entering at the source-end and leaving from the opposite end. The shape of the steady-state concentration profile and therefore the gradient field depends on the porosity (p). The root mean square (rms) displacements of fluid and its constituents (tracers) show a drift power-law behavior, R∝t in the asymptotic regime (t→∞). The flux current density (j) is found to scale with the porosity according to, j∝(Δp)^β with Δp …

Host-Switching Does Not Circumvent The Ni-Based Defence Of The Ni Hyperaccumulator Streptanthus Polygaloides (Brassicaceae), Micheal A. Davis, Robert S. Boyd, James H. Cane

Faculty Publications

Elevated tissue concentrations of metals have been shown to defend metal-hyperaccumulating plants against both herbivores and pathogens. Tolerance of metal-based defences presents a challenge to herbivores, because heavy metals cannot be degraded or metabolized. One strategy that herbivores can employ to counter high-metal defences is dietary dilution, or host switching. Highly mobile herbivores are most likely to use this strategy, but less mobile lepidopteran larvae can also Improve their performance on toxic hosts if early instar development occurs on more favourable hosts. We examined the effects of host switching on growth and survival of a generalist folivore. Specifically, we tested …

A Dipolar Coupling Based Strategy For Simultaneous Resonance Assignment And Structure Determination Of Protein Backbones, Fang Tian, Homayoun Valafar, James H. Prestegard

Faculty Publications

A new approach for simultaneous protein backbone resonance assignment and structure determination by NMR is introduced. This approach relies on recent advances in high-resolution NMR spectroscopy that allow observation of anisotropic interactions, such as dipolar couplings, from proteins partially aligned in field ordered media. Residual dipolar couplings are used for both geometric information and a filter in the assembly of residues in a sequential manner. Experimental data were collected in less than one week on a small redox protein, rubredoxin, that was 15N enriched but not enriched above 1% natural abundance in 13C. Given the acceleration possible with partial 13C …

Economic Hardship As Coercion Under The Protocol On International Trafficking In Persons By Organized Crime Elements, Linda A. Malone

Faculty Publications

No abstract provided.

Using Ssm Proxies To Provide Efficient Multiple-Source Multicast Delivery, Daniel Zappala, Aaron Fabbri

Faculty Publications

We consider the possibility that single-source multicast (SSM) will become a universal multicast service, enabling large-scale distribution of content from a few well-known sources to a general audience. Operating under this assumption, we explore the problem of building the traditional IP model of any-source multicast on top of SSM. Toward this end, we design an SSM proxy service that allows any sender to efficiently deliver content to a multicast group. We demonstrate the performance improvements this service offers over standard SSM and describe extensions for access control, dynamic proxy discovery, and multicast proxy distribution.

Ortho-Planar Linear-Motion Springs, John J. Parise, Larry L. Howell, Spencer P. Magleby

Faculty Publications

This paper presents an ortho-planar spring design that operates by raising or lowering its platform relative to the base with no rotation. The compact nature of the design, and its non-rotating motion, eliminates the problem of rotation against adjoining surfaces and is less sensitive to variation in assemblies than many current compact springs. Nomenclature is presented to identify different configurations, mathematical equations are provided that accurately model the force-defection relationships, and a pneumatic valve positioner application is demonstrated.

Stacked Subwavelength Gratings As Circular Polarization Filters, Gregory P. Nordin, P. C. Deguzman

Faculty Publications

We have stacked subwavelength gratings (SWGs) on a single substrate to create a compact, integrated circular polarization filter. The SWGs consist of a wire grid polarizer and a broadband form-birefringent quarter-wave plate (QWP). Rigorous coupled-wave analysis was used to design the QWP for operation over the 3.5-5.0 m wavelength range. The fabricated silicon broadband QWP exhibited a phase retardance of 82-97° across this wavelength range. Two stacked structures are presented, each with a different wire grid polarizer fabricated on an organic planarization layer (SU-8) that is deposited on a QWP grating. Transmittance measurements of the first structure when illuminated with …

Si3N4/Algan/Gan-Metal-Insulator-Semiconductor Heterostructure Field-Effect Transistors, X. Hu, A. Koudymov, Grigory Simin, J. Yang, M. Asif Khan, A. Tarakji, M. S. Shur, R. Gaska

Faculty Publications

We report on a metal–insulator–semiconductor heterostructurefield-effect transistor (MISHFET) using Si₃N₄ film simultaneously for channel passivation and as a gate insulator. This design results in increased radio-frequency (rf) powers by reduction of the current collapse and it reduces the gate leakage currents by four orders of magnitude. A MISHFET room temperature gate current of about 90 pA/mm increases to only 1000 pA/mm at ambient temperature as high as 300 °C. Pulsed measurements show that unlike metal–oxide–semiconductor HFETs and regular HFETs, in a Si₃N₄ MISHFET, the gate voltage amplitude required for current collapse is much higher …

Long-Slit Observations Of Extended C Ii Λ1335 Emission Around V854 Centauri And Ry Sagittarii, G. C. Clayton, T. R. Ayres

Faculty Publications

We have obtained long-slit far-ultraviolet (1150-1730 Å) spectra of the R Coronae Borealis (RCB) stars V854 Cen and RY Sgr near maximum light and pulsational phase zero with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. The far-UV spectrum of each star shows a photospheric continuum rising steeply toward longer wavelengths and a prominent emission feature at C II λ1335. RY Sgr displays a second, but fainter, emission attributed to Cl I λ1351 (which is radiatively fluoresced by C II λ1335), but Cl I is weak or absent in V854 Cen. Most surprisingly, the C II emission …

Modeling The Effects Of Transforming Growth Factor-Beta On Extracellular Matrix Alignment In Dermal Wound Repair, J. C. Dallon, J. A. Sherratt, P. K. Maini

Faculty Publications

We present a novel mathematical model for collagen deposition and alignment during dermal wound healing, focusing on the regulatory effects of TGF. Our work extends a previously developed model which considers the interactions between fibroblasts and extracellular matrix, composed of collagen and a fibrin based blood clot, by allowing fibroblasts to orient the collagen matrix, and produce and degrade the extracellular matrix, while the matrix can direct the fibroblasts and control their speed. Here we extend the model by allowing a time varying concentration of TGF to alter the properties of the fibroblasts. Thus we are able to simulate experiments …

Review Of The Healing Wound: Experiences And Reflections, Germany, 1938-2000, Michael F. Russo

Faculty Publications

No abstract provided.

Induced Strain Mechanism Of Current Collapse In Algan/Gan Heterostructure Field-Effect Transistors, Grigory Simin, A. Koudymov, A. Tarakji, X. Hu, J. Yang, M. Asif Khan, M. S. Shur, R. Gaska

Faculty Publications

Gated transmission line model pattern measurements of the transient current–voltage characteristics of AlGaN/GaN heterostructurefield-effect transistors(HFETs) and metal–oxide–semiconductor HFETs were made to develop a phenomenological model for current collapse. Our measurements show that, under pulsed gate bias, the current collapse results from increased source–gate and gate–drain resistances but not from the channel resistance under the gate. We propose a model linking this increase in series resistances (and, therefore, the current collapse) to a decrease in piezoelectriccharge resulting from the gate bias-induced nonuniform strain in the AlGaN barrier layer.

Deformations Of The Fermion Realization Of The Sp(4) Algebra And Its Subalgebras, K. D. Sviratcheva, A. I. Georgieva, V. G. Gueorguiev, J. P. Draayer, M. I. Ivanov

Faculty Publications

With a view towards future applications in nuclear physics, the fermion realization of the compact symplectic sp(4) algebra and its q-deformed versions are investigated. Three important reduction chains of the sp(4) algebra are explored in both the classical and deformed cases. The deformed realizations are based on distinct deformations of the fermion creation and annihilation operators. For the primary reduction, the su(2) substructure can be interpreted as either the spin, isospin or angular momentum algebra, whereas for the other two reductions su(2) can be associated with pairing between fermions of the same type or pairing between two distinct fermion types. …

Origin Of Lateral Variation Of Seismic Wave Velocities And Density In The Deep Mantle, Shun Ichiro Karato, Bijaya B. Karki

Faculty Publications

Strong constraints can be placed on the origin of heterogeneity of seismic wave velocities and density if the observed ratios of various parameters are compared with mineral physics predictions. They include the shear to compressional wave velocity heterogeneity ratio, R ≡ δ log V / δ log V , the bulk sound to shear wave velocity heterogeneity ratio, R ≡ δ log V / δ log V , and the density to velocity heterogeneity ratio, R ≡ δ log ρ / δ log V . Using mineral physics considerations, we calculate these ratios in the lower mantle corresponding to the …

Readout And Control Of A Power-Recycled Interferometric Gravitational-Wave Antenna, Peter Fritschel, Rolf Bork, Gabriela González, Nergis Mavalvala, Dale Ouimette, Haisheng Rong, Daniel Sigg, Michael Zucker

Faculty Publications

Interferometric gravitational-wave antennas are based on Michelson interferometers whose sensitivity to small differential length changes has been enhanced by the addition of multiple coupled optical resonators. The use of optical cavities is essential for reaching the required sensitivity but sets challenges for the control system, which must maintain the cavities near resonance. The goal for the strain sensitivity of the Laser Interferometer Gravitational-Wave Observatory (LIGO) is 10-21 rms, integrated over a 100-Hz bandwidth centered at 150 Hz. We present the major design features of the LIGO length and frequency sensing and control system, which will hold the differential length to …

Chromosomal Inversions And The Reproductive Isolation Of Species, M. A.F. Noor, K. L. Gratos, L. A. Bertucci, J. Reiland

Faculty Publications

Recent genetic studies have suggested that many genes contribute to differences between closely related species that prevent gene exchange, particularly hybrid male sterility and female species preferences. We have examined the genetic basis of hybrid sterility and female species preferences in Drosophila pseudoobscura and Drosophila persimilis, two occasionally hybridizing North American species. Contrary to findings in other species groups, very few regions of the genome were associated with these characters, and these regions are associated also with fixed arrangement differences (inversions) between these species. From our results, we propose a preliminary genic model whereby inversions may contribute to the speciation …

Two Different One-Dimensional Structural Motifs In The Same Coordination Polymer: A Novel Interpenetration Of Infinite Ladders By Bundles Of Infinite Chains, Badruz Zaman, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

A coordination polymer with a novel structural motif
consisting of stacks of infinite ladders interpenetrated by
bundles of infinite chains is described; geometrical arguments
are made for the requirements that can lead to such
interpenetration as a function of ligand dimensions.

Statistics And Supermetallicity: The Metallicity Of Mu Leonis, B. J. Taylor

Faculty Publications

For the often-studied "SMR" giant µ Leo, Smith & Ruck (2000) have recently found that [Fe/H] approximately + 0.3 dex. Their conclusion is tested here in a "statistical" paradigm, in which statistical principles are used to select published high-dispersion µ Leo data and assign error bars to them. When data from Smith & Ruck and from Takeda et al. (1998) are added to a data base compiled in 1999, it is found that conclusions from an earlier analysis (Taylor 1999c) are essentially unchanged: the mean value of [Fe/H] approximately + 0.23 ± 0.025 dex, and values ≤ + 0.2 dex …

Jesus The Way, The Cross, And The World According To The Gospel Of John, Craig R. Koester

Faculty Publications

According to the internal logic of John's Gospel, Jesus' claim to be "the way, the truth, and the life" is a remarkably inclusive statement, with none of the exclusive character sometimes attributed to it.

The American Militia And The Origin Of Conscription: A Reassessment, Jeffrey Rogers Hummel

Faculty Publications

No abstract provided.

Introducing Cooperative Learning Through A Faculty Instructional Development Program, Nikos J. Mourtos, Emily L. Allen

Faculty Publications

Cooperative Learning was officially introduced in the College of Engineering at San Jose State University in 1995 with a two-day workshop. The Faculty Instructional Development Program in the college maintains interest in the subjsect and provides support for instructors who use Cooperative Learning, through workshops and informal discussions (Conversations on Teaching). This paper discusses the effectiveness of the program in introducing, promoting, and implementing Cooperative Learning among the faculty and students in the college of engineering. A variety of performance criteria have been used in this assessment, some faculty-centered and some student-centered. The results indicate that although a relatively small …

Top Ten Reasons To Be A Law School Dean, R. Lawrence Dessem

Faculty Publications

Serving as a law school dean can be tough duty. Many people, particularly law school faculty members, have asked over the years why anyone would ever take such a position. This question is particularly relevant because the likely alternative for most deans is service as a full-time professor on a law school faculty-which is, without a doubt, one of the world's truly great jobs..

Distilling The Essence Of Contract Terms: An Anti-Antiformalist Approach To Contract And Employment Law, Rafael Gely

Faculty Publications

A look at the development of labor and employment law in the U.S. reveals one astonishing principle. There is an underlying assumption that employers own the time and activities of employees, and thus any change in the allocation of rights between employers and employees has to be justified against the “interference” with the rights of employers. For example, whenever legislation has been introduced intended to protect workers' rights, employers have argued that such protections will interfere with the right of employers to control their employees. This argument has been successfully made many times, and it has, I argue, shaped the …

Review Of Interrogations: The Nazi Elite In Allied Hands, Michael F. Russo

Faculty Publications

No abstract provided.

Tort Recovery For Loss Of A Chance, David A. Fischer

Faculty Publications

Tort lawyers in the United States often think of “loss of a chance” as a theory of “probabilistic causation” that only applies to medical malpractice misdiagnosis cases. The theory is that if a physician negligently fails to diagnose a curable disease, and the patient is harmed by the disease, the physician should be liable for causing the “loss of a chance” of a cure. We shall see that if the chance of a cure is less than 50 percent, the plaintiff cannot prove by a preponderance of evidence that the negligence caused the harm, and would recover no damages under …

A Tale Of Three Statutes . . . (And One Industry): A Case Study On The Competitive Effects Of Regulation, Rafael Gely

Faculty Publications

The comparison of the three labor regulatory regimes raises an interesting counterexample to the traditional model of regulation. Instead of adopting a one-size-fits-all model, could a regulatory model be conceptualized where a menu of regulatory options is made available to the target population? Under such an approach those affected by the regulatory regime will choose among the various regulatory options and adopt those that better fit their particular situations. Part IV.B develops the basic parameters of this proposal. The article ends with a brief conclusion.