Digital Commons Network^™

Local Systems On Nilpotent Orbits And Weighted Dynkin Diagrams, Pramod N. Achar, Eric N. Sommers

Faculty Publications

We study the Lusztig-Vogan bijection for the case of a local system. We compute the bijection explicitly in type A for a local system and then show that the dominant weights obtained for different local systems on the same orbit are related in a manner made precise in the paper. We also give a conjecture (putatively valid for all groups) detailing how the weighted Dynkin diagram for a nilpotent orbit in the dual Lie algebra should arise under the bijection. © 2002 American Mathematical Society.

An Extension Of Elton's L(1)(N) Theorem To Complex Banach Spaces, S J. Dilworth, Joseph P. Patterson

Faculty Publications

No abstract provided.

Review: Kants Naturtheoretische Begriffe (1747-1780). Eine Datenbank Zu Ihren Expliziten Und Impliziten Vernetzungen., Konstantin Pollok

Faculty Publications

No abstract provided.

Comparative Proteome Analysis Of Brucella Melitensis Vaccine Strain Rev 1 And A Virulent Strain, 16m, Michel Eschenbrenner, Mary Ann Wagner, Troy A. Horn, Jo Ann Kraycer, Cesar V. Mujer, Sue Hagius, Philip Elzer, Vito G. Delvecchio

Faculty Publications

The genus Brucella consists of bacterial pathogens that cause brucellosis, a major zoonotic disease characterized by undulant fever and neurological disorders in humans. Among the different Brucella species, Brucella melitensis is considered the most virulent. Despite successful use in animals, the vaccine strains remain infectious for humans. To understand the mechanism of virulence in B. melitensis, the proteome of vaccine strain Rev 1 was analyzed by two-dimensional gel electrophoresis and compared to that of virulent strain 16M. The two strains were grown under identical laboratory conditions. Computer-assisted analysis of the two B. melitensis proteomes revealed proteins expressed in either 16M …

Alteration Of Oriented Deposition Of Cellulose Microfibrils By Mutation Of A Katanin-Like Microtubule-Severing Protein, David H. Burk, Zheng Hua Ye

Faculty Publications

It has long been hypothesized that cortical microtubules (MTs) control the orientation of cellulose microfibril deposition, but no mutants with alterations of MT orientation have been shown to affect this process. We have shown previously that in Arabidopsis, the fra2 mutation causes aberrant cortical MT orientation and reduced cell elongation, and the gene responsible for the fra2 mutation encodes a katanin-like protein. In this study, using field emission scanning electron microscopy, we found that the fra2 mutation altered the normal orientation of cellulose microfibrils in walls of expanding cells. Although cellulose microfibrils in walls of wild-type cells were oriented transversely …

Non-Semisimple Hopf Algebras Of Dimension P2, Siu Hung Ng

Faculty Publications

Let H be, finite-dimensional Hopf algebra with antipode S of dimension pq over an algebraically closed field of characteristic 0, where p ≤ q are odd primes. If H is not semisimple, then the order of S4 is p, and Tr(S2p) is an integer divisible by p2. In particular, if dim H = p2, we prove that H is isomorphic to a Taft algebra. This completes the classification for the Hopf algebras of dimension p2. © 2002 Elsevier Science (USA). All rights reserved.

Su(3) Versus Deformed Hartree-Fock State, Calvin W. Johnson, Ionel Stetcu, J. P. Draayer

Faculty Publications

Deformation is fundamental to understanding nuclear structure. We compare two ways to efficiently realize deformation for many-fermion wave functions, the leading SU(3) irreducible representation and the angularmomentum-projected Hartree-Fock state. In the absence of single-particle spin-orbit splitting the two are nearly identical. With realistic forces, however, the difference between the two is nontrivial, with the angular-momentum-projected Hartree-Fock state better approximating an "exact" wave function calculated in the fully interacting shell model. The difference is driven almost entirely by the single-particle spin-orbit splitting.

Active Alu Element "A-Tails": Size Does Matter, Astrid M. Roy-Engel, Abdel Halim Salem, Oluwatosin O. Oyeniran, Lisa Deininger, Dale J. Hedges, Gail E. Kilroy, Mark A. Batzer, Prescott L. Deininger

Faculty Publications

Long and short interspersed elements (LINEs and SINEs) are retroelements that make up almost half of the human genome. L1 and Alu represent the most prolific human LINE and SINE families, respectively. Only a few Alu elements are able to retropose, and the factors determining their retroposition capacity are poorly understood. The data presented in this paper indicate that the length of Alu "A-tails" is one of the principal factors in determining the retropositional capability of an Alu element. The A stretches of the Alu subfamilies analyzed, both old (Alu S and J) and young (Ya5), had a Poisson distribution …

Inhibition Of Amyloid-Β Aggregation And Caspase-3 Activation By The Ginkgo Biloba Extract Egb761, Yuan Luo, Julie V. Smith, Vijaykumar Paramasivam, Adam Burdick, Kenneth J. Curry, Justin P. Buford, Ikhlas Khan, William J. Netzer, Huaxi Xu, Peter Butko

Faculty Publications

Standardized extract from the leaves of the Ginkgo biloba tree, labeled EGb761, has been used in clinical trials for its beneficial effects on brain functions, particularly in connection with age-related dementias and Alzheimer's disease (AD). Substantial experimental evidence indicates that EGb761 protects against neuronal damage from a variety of insults, but its cellular and molecular mechanisms remain unknown. Using a neuroblastoma cell line stably expressing an AD-associated double mutation, we report that EGb761 inhibits formation of amyloid-β (Aβ) fibrils, which are the diagnostic, and possibly causative, feature of AD. The decreased Aβ fibrillogenesis in the presence of EGb761 was observed …

Evolution And Dynamics Of Tropical River Plumes In The Great Barrier Reef: An Integrated Remote Sensing And In Situ Study, D.M. Burrage, M.L. Heron, J.M. Hacker, T.C. Stieglitz, C.R. Steinberg, A. Prytz

Faculty Publications

[1] The short-lived but intense discharge of freshwater from tropical rivers into the Great Barrier Reef (GBR) Lagoon and the associated salinity reductions are a critical consideration in marine research and management of the ecologically sensitive GBR World Heritage Area. Salinity provides a unique tracer that gives clues to the origin of river-borne contaminants and allows the influences of storm-induced resuspension and river discharge on turbidity to be clearly distinguished. We describe a field investigation of the evolution and dynamics of the Herbert River plume in the central GBR. Its primary goals were to use an airborne salinity mapper and …

Are Hung Juries A Problem?, Paula Hannaford-Agor, Valerie P. Hans, Nicole L. Mott, G. Thomas Munsterman

Faculty Publications

Providing an empirical picture of hung juries was the principal objective for this 4-year study by the National Center for State Courts (NCSC) with funding by the National Institute of Justice (NIJ). The research methodology was envisioned as a two-phase process. In the first phase, the NCSC proposed to conduct a broad-based survey of hung jury rates in state and federal courts while the second phase consisted of an in-depth examination of jury behavior in 10 jurisdictions to compare case and jury characteristics in felony trials that result in a verdict to those that result in jury deadlock. The types …

Modeling The Thermal Behavior Of A Surface-Micromachined Linear-Displacement Thermomechanical Microactuator, Christian D. Lott, Timothy W. Mclain, John N. Harb, Larry L. Howell

Faculty Publications

Thermomechanical microactuators possess a number of desirable attributes including ease of fabrication and large force and displacement capabilities relative to other types of microactuators. These advantages provide motivation for improving thermomechanical microactuator designs that are more energy efficient and thus better suited for low-power applications. To this end, this paper describes the development and experimental validation of a finite-difference thermal model of a thermomechanical in-plane microactuator (TIM). Comparisons between the model and experimental results demonstrate the importance of including the temperature dependence of several parameters in the model. Strategies for reducing the power and energy requirements of the TIM were …

Captain Moroni's Wartime Strategies: An Application For The Spiritual Battles Of Our Day, Richard J. Mcclendon

Faculty Publications

As Mormon abridged the Nephite record he included what he deemed most relevant for latter-day Israel including stories of war. The so-called war chapters provide a rich resource of modern-day spiritual applications for teachers and students of the gospel (see Alma 43-62). One way to apply these chapters is to draw a parallel between the physical and the spiritual between Moroni's physical battles on the field and the spiritual battles that we face in our own lives today. To be more specific we might ask these questions: (1) What strategies did Captain Moroni use to prepare and protect himself and …

Integrating Marriage Education Into Perinatal Education, Alan J. Hawkins, Tamara Gilliland, Glenda Christiaens, Jason S. Carroll

Faculty Publications

Couples making the transition to parenthood experience challenges that can threaten the quality and stability of their relationships and the health of family members. Currently, the educational infrastructure to support the delivery of couple-relationship education during the transition to parenthood is limited. Because new-parent couples interact with the health care system at many points during this transition time, an opportunity exists for strengthening couple relationships within the system to improve the well-being of adults and children. in this article, we propose a productive collaboration between marriage/couple educators and health care systems to integrate couple-relationship education into the standard of perinatal …

Seeking Salvation For Accountability, Melvin J. Dubnick

Faculty Publications

This is a paper in defense of a concept that is threatened by its popularity and undermined by those who use it most. It is a call for a reexamination and reaffirmation of “accountability” from the perspective of its central role in modern governance. It is a plea for saving the concept of accountability from the abuses it suffers in the hands of friends and advocates. It is an effort at salvation for a concept that has lost its meaningful “soul” in a world filled with rhetoricians, reformers, and functionalists – all well intentioned, but each contributing to accountability’s fall …

Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt

Faculty Publications

Background

This paper examines the mechanism of ultrasonic enhanced drug delivery from Pluronic micelles. In previous publications by our group, fluorescently labeled Pluronic was shown to penetrate HL-60 cells with and without the action of ultrasound, while drug uptake was increased with the application of ultrasound.

Methods

In this study, the amount of uptake of two fluorescent probes, Lysosensor Green (a pH-sensitive probe) and Cell Tracker Orange CMTMR (a pH-independent probe), was measured in HL-60 and HeLa cells.

Results

The results of our experiments show that the increase in drug accumulation in the cells as a result of ultrasonication is …

Correlation Between Volcanic And Tectonic Segmentation Of Fast-Spreading Ridges: Evidence From Volcanic Structures And Lava Flow Morphology On The East Pacific Rise At 9˚-10˚N, Scott M. White, Rachel M. Haymon, D J. Fornari, Michael R. Perfit, Ken C. Macdonald

Faculty Publications

Combined analyses of volcanic features in DSL-120 sonar data and Argo I images along the ridge crest of the East Pacific Rise, 9_090–540N reveal a consistent decrease in inferred lava effusion rate toward the ends of third-order segments. The correlation of tectonic segmentation and volcanic style suggests that third-order segmentation corresponds to the volcanic segmentation of the ridge. Along-axis changes in volcanic structures (from collapse troughs to basaltic lava domes) and lava morphology (from sheet to pillow flows) coincide with the boundaries of morphologically defined third order tectonic segments of the ridge crest visible in shipboard multibeam bathymetry. Pillow lava …

Leading Neutron Production In E+ P Collisions At Hera, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan

Faculty Publications

The production of neutrons carrying at least 20% of the proton beam energy (xL > 0.2) in e+ p collisions has been studied with the ZEUS detector at HERA for a wide range of Q2, the photon virtuality, from photoproduction to deep inelastic scattering. The neutron-tagged cross section, ep → e′ Xn, is measured relative to the inclusive cross section, ep → e′ X, thereby reducing the systematic uncertainties. For xL > 0.3, the rate of neutrons in photoproduction is about half of that measured in hadroproduction, which constitutes a clear breaking of factorisation. There is about a 20% rise in the …

Algebraic Methods For Computer Aided Geometric Design, Thomas W. Sederberg, Jianmin Zheng

Faculty Publications

CAGD draws from several branches of mathematics and computer science, such as approximation theory, differential geometry, and numerical analysis. This chapter reviews some of the tools of algebra and algebraic geometry that have been brought to bear on problems in CAGD.

Metabotropic Glutamate Receptor 5 And Calcium Signaling In Retinal Amacrine Cells, Romina Sosa, Brian Hoffpauir, Michele L. Rankin, Richard C. Bruch, Evanna L. Gleason

Faculty Publications

To begin to understand the modulatory role of glutamate in the inner retina, we examined the mechanisms underlying metabotropic glutamate receptor 5 (mGluR5)-dependent Ca2+ elevations in cultured GABAergic amacrine cells. A partial sequence of chicken retinal mGluR5 encompassing intracellular loops 2 and 3 suggests that it can couple to both Gq and Gs. Selective activation of mGluR5 stimulated Ca2+ elevations that varied in waveform from cell to cell. Experiments using high external K+ revealed that the mGluR5-dependent Ca2+ elevations are distinctive in amplitude and time course from those engendered by depolarization. Experiments with a Ca2+-free external solution demonstrated that the …

A Metadata Approach To Preservation Of Digital Resources: The University Of North Texas Libraries' Experience, Daniel Gelaw Alemneh, Samantha K. Hastings, Cathy Hartman

Faculty Publications

Preserving long-term access to digital information resources is one of the key challenges facing libraries and information centers today. The University of North Texas (UNT) Libraries has entered into partnership agreements with federal and state agencies to ensure permanent storage and public access to a variety of government information sources. As digital resource preservation encompasses a wide variety of interrelated activities, the UNT Libraries are taking a phased approach to ensure the long-term access to its digital resources. Formulation of preservation policy and creation of preservation metadata for electronic files and digital collections are among the most important steps. This …

Effects Of Prescribed Burning On Vegetation And Fuel Loading In Three East Texas State Parks, S. Rideout, Brian P. Oswald

Faculty Publications

-This study was conducted to evaluate the initial effectiveness of prescribed burning in the ecological restoration of forests within selected parks in east Texas. Twenty-four permanent plots were installed to monitor fuel loads, overstory, sapling, seedling, shrub and herbaceous layers within bum and control units of Mission Tejas, Tyler and Village Creek state parks. Measurements were taken during the summers of 1999 and 2000. Prescribed burning was conducted between these sampling periods in early spring 2ooo. Results indicated that the current applications of prescribed burning do not significantly influence vegetation or fuels. Sustained drought, prior management practices and imposed local …

Element Ratios And Aquatic Food Webs, R. Eugene Turner

Faculty Publications

Organic matter is the result of concentrating a few non-metals that are relatively rare in the earth’s crust. Most of these essential elements are in a rough proportionality within phylogenetic groupings. Life is thus working against a concentration gradient to extract or accumulate these elements, and this metabolic work is accomplished in interrelated and often subtle ways for many other elements. The physiological requirement to sustain these elemental ratios (commonly discussed in terms of the N∶P ratios, but also C∶N, C∶P, and Si∶N ratios) constrains organization at the cellular, organism, and community level. Humans, as geochemical engineers, significantly influence the …

Echoes In X-Ray Binaries, K. O'Brien, Keith Horne, R. I. Hynes, W. Chen, C. A. Haswell, M. D. Still

Faculty Publications

We present a method of analysing the correlated X-ray and optical/UV variability in X-ray binaries, using the observed time delays between the X-ray driving light curves and their reprocessed optical echoes. This allows us to determine the distribution of reprocessing sites within the binary. We model the time-delay transfer functions by simulating the distribution of reprocessing regions, using geometrical and binary parameters. We construct best-fitting time-delay transfer functions, showing the regions in the binary responsible for the reprocessing of X-rays. We have applied this model to observations of the soft X-ray transient GRO J1655-40. We find that the optical variability …

Experimental Demonstration Of Multiple Robot Cooperative Target Intercept, Timothy W. Mclain, Randal W. Beard, Jed M. Kelsey

Faculty Publications

This paper presents experimental results for the simultaneous intercept of preassigned targets by a team of mobile robots. The robots are programmed to mimic the dynamic behavior of unmanned air vehicles in constant-altitude flight. In proceeding to their targets, robots must avoid both known static threats and pop-up threats. An overview of the cooperative control strategy followed is given, as well as a description of the robot hardware and software used. Experimental results demonstrating simultaneous intercept of targets by the robot team are presented.

Application Of The New Vanishing Interfacial Tension Technique To Evaluate Miscibility Conditions For The Terra Nova Offshore Project, Dandina N. Rao, J. I. Lee

Faculty Publications

Terra Nova oil pool is the second largest oil pool discovered in the Grand Banks of the Canadian East Coast and is under development. As a part of the oil recovery process selection criteria, miscibility conditions were determined for Terra Nova oil with various enrichment levels of gas available from the offshore production facilities using the recently developed vanishing interfacial tension (VIT) technique. The VIT technique is based on the concept that the interfacial tension between the gas and crude oil phases at reservoir temperature must reduce to zero as these two phases approach the point of miscibility. The concept …

Low-Loss High Power Rf Switching Using Multifinger Algan/Gan Moshfets, Alexei Koudymov, Xuhong Hu, Kirill Simin, Grigory Simin, Mohammod Ali, Jinwei Yang, M. Asif Khan

Faculty Publications

We demonstrate a novel RF switch based on a multifinger AlGan/GaN MOSHFET. Record high saturation current and breakdown voltage, extremely low gate leakage current and low gate capacitance of the III-N MOSHFETs make them excellent active elements for RF switching. Using a single element test circuit with 1-mm wide multifinger MOSHFET we achieved 0.27 dB insertion loss and more than 40 dB isolation. These parameters can be further improved by impedance matching and by using submicron gate devices. The maximum switching power extrapolated from the results for 1a/mm 100 mum wide device exceeds 40 W for a 1-mm wide 2-a/mm …

Intellectual Access: Introduction To The Organization Of Information, Anita Coleman

Faculty Publications

This is a presentation to the Strong Start program (new MLS students) at the University of Arizona on 19 August 2002. There are 32 slides. Contents: Definitions, Assumptions, Limitations; What are Information Environments? The Roles We Play; Knowledge Organization (KO); The Cataloging/Metadata Process; Metadata â standards, types, initiatives; Q & A; Discussion; Resources. Interestingly, dLIST is mentioned and volunteers solicited!

Simulations Of The Instability Of The M = 1 Self-Shielding Diocotron Mode In Finite-Length Non-Neutral Plasmas, Grant W. Mason, Ross L. Spencer

Faculty Publications

The "self-shielding" m = 1 diocotron mode in Malmberg-Penning traps has been known for over a decade to be unstable for finite length non-neutral plasmas with hollow density profiles. Early theoretical efforts were unsuccessful in accounting for the exponential growth and/or the magnitude of the growth rate. Recent theoretical work has sought to resolve the discrepancy either as a consequence of the shape of the plasma ends or as a kinetic effect resulting from a modified distribution function as a consequence of the protocol used to form the hollow profiles in experiments. Both of these finite length mechanisms have been …

Viewpoint: Experimental Recovery Of Geometrically Necessary Dislocation Density In Polycrystals, Brent L. Adams, Bassem S. El-Dasher, Anthony D. Rollett

Faculty Publications

The authors wish to thank The Alcoa Technical Research Center for supplying the specimens and performing the compression tests. This work was supported primarily by the MRSEC program of the National Science Foundation under DMR-0079996. Application of electron backscattering diffraction methods to recover estimates of the geometrically necessary dislocation density is described. The limitations of the method arising from the opacity of crystalline materials and the spatial and angular resolution limits are discussed.