Physical Sciences and Mathematics Commons^™

Interagency Science And Research: Quarterly Progress Report, Period Ending September 30, 2005, Margaret N. Rees

Interagency Science and Research Strategy

• Search for project manager was successfully completed in September 2005
• Project manager Debra Dandridge will start half-time (telecommuting) on November 1, 2005, and begins in Las Vegas full-time on January 1, 2006

Take Pride In America In Southern Nevada: Quarterly Progress Report, Period Ending September 30, 2005, Take Pride In America In Southern Nevada

Anti-littering Programs

• Interagency Anti-Litter Team met on August 22 and September 14, 2005.
• Community Anti-Litter Steering Committee participants have been identified.
• Project Manager Doug Joslin has been recommended for appointment to the new county-wide Southern Nevada Recycling Advisory Committee.
• Five Take Pride in America public service announcements were produced and delivered to television stations in southern Nevada.
• A messaging campaign proposal will be shared with the federal land managers on October 27, 2005.
• An initial review of progress on the Spring Mountains anti-litter pilot project has been conducted.
• Three Take Pride in America clean-up events were supported by the Anti-Litter Team. The …

Afci Quarterly Input – Unlv July 1 Through September 30, 2005, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

Quarterly report highlighting research projects, activities and objectives of the Transmutation Research Program at the Nuclear Science & Technology Division, Harry Reid Research Center.The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.

Crystalline Particle Packings On A Sphere With Long Range Power Law Potentials, Mark Bowick, Angelo Cacciuto, David R. Nelson, Alex Travesset

Physics - All Scholarship

The original Thomson problem of "spherical crystallography" seeks the ground state of electron shells interacting via the Coulomb potential; however one can also study crystalline ground states of particles interacting with other potentials. We focus here on long range power law interactions of the form 1/r^gamma (0 < \gamma < 2), with the classic Thomson problem given by gamma=1. At large R/a, where R is the sphere radius and a is the particle spacing, the problem can be reformulated as a continuum elastic model that depends on the Young's modulus of particles packed in the plane and the universal (independent of the pair potential) geometrical interactions between disclination defects. The energy of the continuum model can be expressed as an expansion in powers of the total number of particles, M sim (R/a)^2, with coefficients explicitly related to both geometric and potential-dependent terms. For icosahedral configurations of twelve 5-fold disclinations, the first non-trivial coefficient of the expansion agrees with explicit numerical evaluation for discrete particle arrangements to 4 significant digits; the discrepancy in the 5th digit arises from a contribution to the energy that is sensitive to the particular icosadeltahedral configuration and that is neglected in the continuum calculation. In the limit of a very large number of particles, an instability toward grain boundaries can be understood in terms of a "Debye{--}Huckel" solution, where dislocations have continuous Burgers' vector "charges". Discrete dislocations in grain boundaries for intermediate particle numbers are discussed as well.

Footprints Of Statistical Anisotropies, Christian Armendariz-Picon

Physics - All Scholarship

We propose and develop a formalism to describe and constrain statistically anisotropic primordial perturbations. Starting from a decomposition of the primordial power spectrum in spherical harmonics, we find how the temperature fluctuations observed in the CMB sky are directly related to the coefficients in this harmonic expansion. Although the angular power spectrum does not discriminate between statistically isotropic and anisotropic perturbations, it is possible to define analogous quadratic estimators that are direct measures of statistical anisotropy. As a simple illustration of our formalism we test for the existence of a preferred direction in the primordial perturbations using full-sky CMB maps. …

Feature-Specific Penalized Latent Class Analysis For Genomic Data, E. Andres Houseman, Brent A. Coull, Rebecca A. Betensky

Harvard University Biostatistics Working Paper Series

No abstract provided.

Expanding The Use Of Cellular Automata, Joseph Bertles

Computer Science Honors Theses

Cellular automata are a type of simulation based upon dividing space into cells. More specifically, cellular automata are characterized by parallelism, locality, and homogeneity. A simulation is run by conducting a series of updates, consisting of running a set of rules that all cells follow. The rules typically consist of looking at a cell's immediate neighbors and/or itself to determine what will be in the cell at the next step. The rules are applied to all the cells at exactly the same time in exactly the same manner. The use of cellular automata has been limited to computer scientists, those …

Rate-Adaptive Runlength Limited Encoding For High-Speed Infrared Communication, James Cyril Funk

Theses and Dissertations

My thesis will demonstrate that Rate Adaptive Runlength Limited encoding (RA-RLL) achieves high data rates with acceptable error rate over a wide range of signal distortion/attenuation, and background noise. RA-RLL has performance superior to other infrared modulation schemes in terms of bandwidth efficiency, duty cycle control, and synchronization frequency. Rate adaptive techniques allow for quick convergence of RA-RLL parameters to acceptable values. RA-RLL may be feasibly implemented on systems with non-ideal timing and digital synchronization.

Steady States Of A Nonequilibrium Lattice Gas, Edward Lyman, Beate Schmittmann

Beate Schmittmann

We present a Monte Carlo study of a lattice gas driven out of equilibrium by a local hopping bias. Sites can be empty or occupied by one of two types of particles, which are distinguished by their response to the hopping bias. All particles interact via excluded volume and a nearest-neighbor attractive force. The main result is a phase diagram with three phases: a homogeneous phase and two distinct ordered phases. Continuous boundaries separate the homogeneous phase from the ordered phases, and a first-order line separates the two ordered phases. The three lines merge in a nonequilibrium bicritical point.

Limits Of Quintessence, R. R. Caldwell, Eric V. Linder

Dartmouth Scholarship

We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase plane of w and w′, the dark energy equation of state and its time derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely a scalar field can resemble a cosmological constant. These results, indicating a desired measurement resolution of order σ(w′)≈(1+w), …

Development Of Database And Web Site For D3multisport, Jay Garrison

Regis University Student Publications (comprehensive collection)

Before this project, D3Multisport.com did not have a software application to track and monitor personal and progress information on athletes training for triathlon events. The previous process was manual, and although it helped provide a training schedule for an athlete it required the data be updated by hand. The process of developing a training program on an excel spreadsheet provided a good basis for the athlete to start the program, but was not suited to make dynamic adjustments if not optimally suited for the athlete. The application created in this project was designed to keep a coach updated on the …

Hs 2331+3905: The Cataclysmic Variable That Has It All, S. Araujo-Betancor, B. T. Gänsicke, H.-J. Hagen, T. R. Marsh, E T. Harlaftis, J Thorstensen

Dartmouth Scholarship

We report detailed follow-up observations of the cataclysmic variable HS 2331+3905, identified as an emission- line object in the Hamburg Quasar Survey. An orbital period of 81.08 min is unambiguously determined from the detection of eclipses in the light curves of HS 2331+3905. A second photometric period is consistently detected at P ≃ 83.38 min, ∼2.8% longer than Porb, which we tentatively relate to the presence of permanent superhumps. High time resolution photometry exhibits short-timescale variability on time scales of ≃5−6 min which we interpret as non-radial white dwarf pulsations, as well as a coherent signal at 1.12 min, which …

Continuations From Generalized Stack Inspection, Greg Pettyjohn, John Clements, Joe Marshall, Shriram Krishnamurthi, Matthias Felleisen

Computer Science and Software Engineering

Implementing first-class continuations can pose a challenge if the target machine makes no provisions for accessing and re-installing the run-time stack. In this paper, we present a novel translation that overcomes this problem. In the first half of the paper, we introduce a theoretical model that shows how to eliminate the capture and the use of first-class continuations in the presence of a generalized stack inspection mechanism. The second half of the paper explains how to translate this model into practice in two different contexts. First, we reformulate the servlet interaction language in the PLT Web server, which heavily relies …

A Facile Synthesis Of (Tert-Alkoxy)Amines, Hasan Palandoken, Chris M. Bocian, Michelle R. Mccombs, Michael H. Nantz

Chemistry and Biochemistry

Tertiary alcohols react with stoichiometric BF₃·Et₂O and N-hydroxyphthalimide to yield N-alkoxyphthalimides. Subsequent hydrazinolyses afford the title compounds.

Marginal Regression Modeling Under Irregular, Biased Sampling, Petra Buzkova, Thomas Lumley

UW Biostatistics Working Paper Series

In longitudinal studies observations are often obtained at continuous subject-specific times. Frequently the availability of outcome data may be related to the outcome measure or other covariates that are related to the outcome measure. Under such biased sampling designs unadjusted regression analysis yield biased estimates. Building on the work of Lin & Ying (2001) that integrates counting processes techniques with longitudinal data settings we propose a class of estimators that can handle biased sampling. We call those estimators ``inverse--intensity--rate--ratio--weighted'' (IIRR) estimators. Of major focus is a mean--response model where we examine the marginal effect of the covariate X at time …

Longitudinal Data Analysis For Generalized Linear Models Under Irregular, Biased Sampling: Situations With Follow-Up Dependent On Outcome Or Auxiliary Outcome-Related Variables, Petra Buzkova, Thomas Lumley

UW Biostatistics Working Paper Series

In longitudinal studies, observations are often obtained at subject-specific observation times. Those times can be continuous times, not at a set of prespecified times. Frequently the observation times may be related to the outcome measure or other auxiliary variables that are related to the outcome measure but undesirable to condition upon in the regression model for outcome. Regression analysis unadjusted for such sampling designs yield biased estimates. Based on estimating equations, we propose a class of estimators in generalized linear regression models that can handle biased sampling under continuous observation times. We call those estimators ``inverse--intensity rate--ratio--weighted'' (IIRR) estimators. The …

Semiparametric Loglinear Regression For Longitudinal Measurements Subject To Irregular, Biased Follow-Up, Petra Buzkova, Thomas Lumley

UW Biostatistics Working Paper Series

We propose a method for analysis of loglinear regression models for longitudinal data that are subject to continuous and irregular follow-up. Frequently, if the follow-up is irregular, the availability of outcome data may be related to the outcome measure or other covariates that are related to the outcome measure. Under such biased sampling designs unadjusted regression analysis yield biased estimates. We examine the marginal association of the covariates X at time t and the logarithm of the mean of response Y at time t. We focus on semiparametric regression with unspecified baseline function of time. To predict the follow-up times …

Dynamics Of Trapped Bright Solitons In The Presence Of Localized Inhomogeneities, G. Herring, Panos Kevrekidis, R. Carretero-Gonzalez, B. A. Malomed, D. J. Frantzeskakis, A. R. Bishop

Panos Kevrekidis

We examine the dynamics of a bright solitary wave in the presence of a repulsive or attractive localized ``impurity'' in Bose-Einstein condensates (BECs). We study the generation and stability of a pair of steady states in the vicinity of the impurity as the impurity strength is varied. These two new steady states, one stable and one unstable, disappear through a saddle-node bifurcation as the strength of the impurity is decreased. The dynamics of the soliton is also examined in all the cases (including cases where the soliton is offset from one of the relevant fixed points). The numerical results are …

Metal Hybridization And Electronic Structure Of Tris(8-Hydroxyquinolato)Aluminum (Alq3), Anthony N. Caruso, D. L. Schulz, Peter A. Dowben

Peter Dowben Publications

The metal-organic complex Tris(8-hydroxyquinolato)aluminum (Alq₃) has been studied by energy and light polarization dependent photoemission. Resonant photoemission was used to identify the molecular orbitals involved in metal chelation. When adsorbed on cobalt and gold surfaces, marked differences in the Alq₃ metal-to-ligand bonds were observed. The results indicate intramolecular aluminum-to-ligand bonding through the oxygen heteroatom when Alq₃ is adsorbed on gold, but through the nitrogen heteroatom when on cobalt. These results indicate that substrate interfacial complex formation plays an important role in the Alq₃ molecular configuration and intramolecular bonding.

Structured Object-Oriented Co-Analysis/Co-Design Of Hardware/Software For The Facts Powers System, Matt Ryan, Sojan Markose, Xiaoqing Frank Liu, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

There are several approaches to the hardware/software design in embedded systems, ranging from the traditional sequential methods which focus on the determination of the hardware architecture prior to software design, to newer object-oriented approaches that attempt to apply software engineering methods to hardware design without a systematic process. This paper discusses a structured object-oriented methodology for the integrated co-analysis and co-design of hardware/software systems using an extended high order object-oriented modeling technique (HOOMT). This methodology offers a uniform method for hardware and software developers to jointly develop the specifications for and partitioning of the hardware and software components of a …

Can A Divorced Mom/Dad Take Care Of The Child?, Vijay Dialani

Vijay Dialani

Laziness Without All The Hard Work: Combining Lazy And Strict Languages For Teaching, Eli Barzilay, John Clements

Computer Science and Software Engineering

Students have trouble understanding the difference between lazy and strict programming. It is difficult to compare the two directly, because popular strict languages and popular lazy languages differ in their syntax, in their type systems, and in other ways unrelated to the lazy/strict evaluation discipline. While teaching programming languages courses, we have discovered that an extension to PLT Scheme allows the system to accommodate both lazy and strict evaluation in the same system. Moreover, the extension is simple and transparent. Finally, the simple nature of the extension means that the resulting system provides a rich environment for both lazy and …

South Florida Coastal Water Quality Monitoring Network - 4-6/05 Quarterly Report (C-15397), Joseph N. Boyer

SERC Research Reports

No abstract provided.

A Bacillus Thuringiensis Isolation Method Utilizing A Novel Stain, Low Selection And High Throughput Produced Atypical Results, Joanne Rampersad-Ammons, David R. Ammons

Chemistry Faculty Publications and Presentations

Background

Bacillus thuringiensis is a bacterium known for producing protein crystals with insecticidal properties. These toxins are widely sought after for controlling agricultural pests due to both their specificity and their applicability in transgenic plants. There is great interest in isolating strains with improved or novel toxin characteristics, however isolating B. thuringiensis from the environment is time consuming and yields relatively few isolates of interest. New approaches to B. thuringiensis isolation have been, and continue to be sought. In this report, candidate B. thuringiensis isolates were recovered from environmental samples using a combination of a novel stain, high throughput and …

A Pseudolikelihood Approach For Simultaneous Analysis Of Array Comparative Genomic Hybridizations (Acgh), David A. Engler, Gayatry Mohapatra, David N. Louis, Rebecca Betensky

Harvard University Biostatistics Working Paper Series

DNA sequence copy number has been shown to be associated with cancer development and progression. Array-based Comparative Genomic Hybridization (aCGH) is a recent development that seeks to identify the copy number ratio at large numbers of markers across the genome. Due to experimental and biological variations across chromosomes and across hybridizations, current methods are limited to analyses of single chromosomes. We propose a more powerful approach that borrows strength across chromosomes and across hybridizations. We assume a Gaussian mixture model, with a hidden Markov dependence structure, and with random effects to allow for intertumoral variation, as well as intratumoral clonal …

A Motion Planning Processor On Reconfigurable Hardware, Nuzhet Atay, Burchan Bayazit

All Computer Science and Engineering Research

Motion planning algorithms enable us to find feasible paths for moving objects. These algorithms utilize feasibility checks to differentiate valid paths from invalid ones. Unfortunately, the computationally expensive nature of such checks reduces the effectiveness of motion planning algorithms. However, by using hardware acceleration to speed up the feasibility checks, we can greatly enhance the performance of the motion planning algorithms. Of course, such acceleration is not limited to feasibility checks; other components of motion planning algorithms can also be accelerated using specially designed hardware. A Field Programmable Gate Array (FPGA) is a great platform to support such an acceleration. …

Search For New Physics Using High-Mass Tau Pairs From 1.96 Tev Pp̅ Collisions, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We present the results of a search for anomalous resonant production of tau lepton pairs with large invariant mass, the first such search using the CDF II Detector in Run II of the Tevatron pp̅ collider. Such anomalous production could arise from various new physics processes. In a data sample corresponding to 195 pb^-1 of integrated luminosity we predict 2.8±0.5 events from standard model background processes and observe 4. We use this result to set limits on the production of heavy scalar and vector particles decaying to tau lepton pairs.

Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly

Theses and Dissertations

Polymeric materials have seen increasing use as microfluidic device substrates due to their low cost and the simplicity of templated fabrication procedures. I showed that poly(methyl methacrylate) (PMMA) microdevices could be enclosed in a boiling water bath, which allowed the seal to form more quickly than in conventional approaches, and enabled microchannels to remain hydrated throughout the bonding process. Microchip capillary electrophoresis (µ-CE) devices were fabricated using water-based enclosure, and a mixture of fluorescently labeled amino acids was separated in 30 s in these microchips. To create more robust capillary electrophoresis (CE) microdevices with improved separation performance, phase-changing sacrificial materials …

Lake-Level Influences On Chironomid-Based Reconstructions Of Paleotemperature, Ann Dieffenbacher-Krall

University of Maine Office of Research Administration: Grant Reports

This award is for support of a study to determine the influence of lake-level changes on chironomid-based temperature estimates. A transect of cores from within each of two lakes in northern Maine will be examined for evidence of past water levels. Chironomid analysis will be performed on cores from both lakes. Geologic/chronologic evidence of Younger Dryas-age ice readvance in northern Maine will provide the data necessary to apply a well-developed glaciological model to determine the range of temperature and precipitation that could possibly have prevailed during this period. Chironomid estimates of temperature will be reconciled with the temperature range derived …

Catena-Poly[[Bis(Α-Thenoyltrifluoroacetonato)Copper(Ii)]-Μ-1,4-Di-4-Pyridyl-2,3-Diazabuta-1,3-Diene], William J. Perkins, Tamara Maxwell, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

In the one-dimensional title polymer, [Cu(C₈H₄F₃O₂S)₂(C₁₂H₁₀N₄)]_n or [Cu(L)₂(tta)₂] [tta is -thenoyltrifluoroacetonato and L is 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene], Cu²⁺ lies on a center of inversion. It is axially coordinated by two pyridyl N atoms from two different L ligands and equatorially coordinated by four O atoms from two chelating tta ligands. The ligand L propagates the one-dimensional chain structure by serving as a bridging ligand between two Cu octahedra via Cu-N coordinate bonds.