Physical Sciences and Mathematics Commons^™

Self-Similarity And Symmetries Of Pascal’S Triangles And Simplices Mod P, Richard P. Kubelka

Richard P. Kubelka

No abstract provided.

The Surface Band Structure Of W(112), Yaroslav B. Losovyj, I. N. Yakovkin, Hae-Kyung Jeong, Peter A. Dowben

Peter Dowben Publications

Both the experimental and theoretical band structure of the W(112) surface are presented, with the theoretical band structure calculated by the film–LAPW (linearized augmented plane waves) method. The results permit one to compare the W(112) and Mo(112) band structures and illuminate the similarities. It is found that for the W(112) surface the main photoemission features combine contributions from both the surface and bulk, as has been previously noted for Mo(112). The main differences between the electronic structures of the furrowed W(112) and Mo(112) surfaces are seen in the width of occupied bands. The differences are attributed to the extent of …

Chaos-Induced Pulse Trains In The Ionization Of Hydrogen, K. A. Mitchell, J. P. Handley, B. Tighe, A. Flower, John B. Delos

Arts & Sciences Articles

We predict that a hydrogen atom in parallel electric and magnetic fields, excited by a short laser pulse to an energy above the classical saddle, ionizes via a train of electron pulses. These pulses are a consequence of classical chaos induced by the magnetic field. We connect the structure of this pulse train (e.g., pulse size and spacing) to fractal structure in the classical dynamics. This structure displays a weak self-similarity, which we call “epistrophic self-similarity.” We demonstrate how this self-similarity is reflected in the pulse train.

Magical Miscellany, Francis Su

All HMC Faculty Publications and Research

What is a Math Fun Fact, you ask? A Math Fun Fact is any mathematical tidbit that can be presented or grasped quickly, is surprising or captivating, can be generally enjoyed by friends of mathematics, and is hopefully fun! Of course, part of the fun is thinking about why the Fun Fact is true--so we won't spoil the fun. Though, we may give you some hints and references

However, since there are infinitely many Math Fun Facts (prove this), we can only bring you a few each time... here are a few whose conclusions might be considered "magical".

High-Quality, Melt-Grown Zno Single Crystals, D. C. Reynolds, C. W. Litton, David C. Look, J. E. Joelscher, B. Claflin, T. C. Collins, J. Nause, B. Nemeth

Physics Faculty Publications

High-quality, melt-grown ZnO crystals are reported. The reflection and emission spectra of the melt-grown samples are compared with the same spectra from high-quality, vapor-grown ZnO crystals. We isolate the reflection and emission spectra predominantly related to the intrinsic properties associated with the wurtzite structure of the crystals. The quality of the crystals is reflected in the spectral reproduction of the intrinsic properties of the crystals. Both the ground state and the n=2 state of the free excitons associated with the A, B, and C valence bands of the crystals are spectrally observed in reflection. Assuming a hydrogenic character for …

No News Is Bad News: Characteristics Of Adolescents Who Provide Neither Parental Consent Nor Refusal For Participation In School-Based Survey Research, C. Anderson Johnson, Jennifer B. Unger, Peggy E. Gallaher, Paula Palmer, Lourdes Baezconde-Garbanati, Dennis R. Trinidad, Steven Cen

CGU Faculty Publications and Research

Schools offer a convenient setting for research on adolescents.However, obtaining active written parental consent is difficult. In a 6th-grade smoking study, students were recruited with two consent procedures: active consent (parents must provide written consent for their children to participate) and implied consent (children may participate unless their parents provide written refusal). Of 4,427 invited students, 3,358 (76%) provided active parental consent, 420 (9%) provided active parental refusal, and 649 (15%) provided implied consent (parental nonresponse). The implied consent procedure recruited more boys, African Americans, students with poor grades, and smokers. This dual-consent procedure is useful for collecting some limited …

Jahn-Teller Distortions, Cation Ordering And Octahedral Tilting In Perovskites, Michael W. Lufaso, Patrick M. Woodward

Chemistry Faculty Research and Scholarship

In transition metal oxides, preferential occupation of specific d orbitals on the transition metal ion can lead to the development of a long-range ordered pattern of occupied orbitals. This phenomenon, referred to as orbital ordering, is usually observed indirectly from the cooperative Jahn-Teller distortions (CJTDs) that result as a consequence of the orbital ordering. This paper examines the interplay between orbital ordering, octahedral tilting and cation ordering in perovskites. Both ternary AMX₃ perovskites containing an active Jahn-Teller (J-T) ion on the octahedral site and quaternary A₂MM'X₆ perovskites containing a J-T ion on one-half of …

Application Of Photopolymer Holographic Gratings, Emilia Mihaylova, Izabela Naydenova, Hosam Sherif, Suzanne Martin, Vincent Toal

Conference Papers

Two optical set-ups for electronic speckle pattern shearing interferometry (ESPSI) using photopolymer diffractive optical elements are presented. Holographic gratings are recorded using an acrylamide based photopolymer material. Since the polymerisation process occurs during recording, the holograms are produced without any development or processing. In both ESPSI systems the photopolymer gratings are used to shear the image. In the first ESPSI system only one grating is used in combination with a sheet of ground glass. The distance between the grating and the ground glass can be used to control the amount of the shear. The sheared images on the ground glass …

Novel Polymerically-Modified Clays Permit The Preparation Of Intercalated And Exfoliated Nanocomposites Of Styrene And Its Copolymers By Melt Blending, Shengpei Su, David D. Jiang, Charles A. Wilkie

Chemistry Faculty Research and Publications

Two new organically-modified clays have been made and used to produce nanocomposites of polystyrene, high impact polystyrene and acrylonitrile–butadiene–styrene terploymer. At a minimum, intercalated nanocomposites of all of these polymers have been produced by melt blending in a Brabender mixer and, in some cases, exfoliated nanocomposites have been obtained. The systems have all been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry and the measurement of mechanical properties. These novel new clays open new opportunities for melt blending of polymers with clays to obtain nanocomposites with important properties.

Geomorphic And Environmental Change Around A Large, Aging Reservoir: Lake C. W. Mcconaughy, Western Nebraska, Usa, R. Matthew Joeckel, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Lake C. W. McConaughy, a 63-year-old manmade reservoir in the North Platte Valley of western Nebraska, is the largest standing body of water in the state. From the time that Kingsley Dam was completed in 1941 until the present day (2004), many geomorphic and environmental changes have occurred along the shores and within the North Platte Valley. Erosion on the southeastern shoreline of the lake had been perceived as a problem for landowners and managers for at least three decades, but the full scale of erosion was revealed only after a cumulative 18-m drawdown in lake level: bedrock platforms, extending …

Trophic Ecology Of The Deep-Sea Fish Malacosteus Niger (Pisces: Stomiidae): An Enigmatic Feeding Ecology To Facilitate A Unique Visual System?, Tracey Sutton

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The ‘dragonfishes’ and their relatives (family Stomiidae) are among the top predators of the mesopelagic zone of the open ocean. Based on feeding morphology (e.g., large gape, long fangs, and no gill-rakers or ethmoid membrane), the meso/bathypelagic fish Malacosteus niger would also be expected to be a large-item predator, as are the other members of its family. However, analysis of specimens from different ocean basins revealed that the most common prey items are calanoid copepods, despite an apparent inability to handle such small prey. Malacosteus niger is considered advanced within the Stomiidae, so this feeding mode represents a secondary reversion …

Interactions Between Zooplankton And Karenia Brevis In The Gulf Of Mexico., Kristen M. Lester, Gabriel A. Vargo, John J. Walsh, Cynthia A. Heil, Mary B. Neely, Danylle N. Spence, Susan Murasko, Tracey Sutton, Scott E. Burghart, Andrew Remsen, T. L. Hopkins, Richard N. Bohrer

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Blooms of the toxic dinoflagellate K. brevis are common in the Gulf of Mexico, yet no in situ studies of the interactions between zooplankton and K. brevis in the Gulf of Mexico have been conducted. Zooplankton numerical abundance, biomass and taxonomic composition of nonbloom and K. brevis bloom stations within the ECOHAB study area were compared. At nonbloom stations, the most important determinant species were Parvolcalanus crassirostris, Oithona colcarva and Paracalanus quasimodo at the 5-m isobath and P. quasimodo, O. colcarva and Oikopleura dioka at the 25-m isobath. There was considerable overlap between the 5 and 25-m isobaths, with …

The Case For An Optically-Thick High-Velocity Broad-Line Region, Stephanie A. Snedden, C. Martin Gaskell

Department of Physics and Astronomy: Faculty Publications

A combined analysis of the profiles of the main broad quasar emission lines in both Hubble Space Telescope and optical spectra shows that while the profiles of the strong UV lines are quite similar, there is frequently a strong increase in the Lyα/Hα ratio in the high-velocity gas. We show that the suggestion that the high velocity gas is optically-thin presents many problems. We show that the relative strengths of the high velocity wings arise naturally in an optically-thick BLR component. An optically-thick model successfully explains the equivalent widths of the lines, the Lyα/Hα ratios and flatter Balmer decrements in …

Projecting Range Expansion Of Invasive European Green Crabs (Carcinus Maenas) To Alaska: Temperature And Salinity Tolerance Of Larvae, Anson Hines, Greg Ruiz, Natasha Gray Hitchcock, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

The European Green Crab (Carcinus maenas) is a global invader, successfully colonizing many world regions and having significant ecological and economic impacts. The Green Crab colonized western North America in the late 1980s, spreading primarily northward from the initial establishment in San Francisco Bay to several other bays in northern California, Oregon, and Washington. Initial analysis, based largely upon temperature tolerance of postlarval crabs, suggests Green Crabs will continue to spread and become established throughout much of Alaska. However, establishment of self-sustaining populations in Alaska may be restricted by environmental conditions for reproduction and larval development, instead of the broad …

A Carbocation Substituted Clay And Its Styrene Nanocomposite, Jinguo Zhang, Charles A. Wilkie

Chemistry Faculty Research and Publications

A substituted tropylium ion can be ion-exchanged onto montmorillonite to give a novel organically-modified clay. One can prepare a polystyrene nanocomposite of this clay by emulsion, but not bulk, polymerization. This is the first example of a clay that contains a carbocation and its use to prepare a polymer-clay nanocomposite. Both the clay and its nanocomposites exhibit outstanding thermal stability. Characterization by X-ray diffraction, transmission electron microscopy, cone calorimetry, thermogravimetric analysis and the evaluation of mechanical properties shows that a mixed intercalated-exfoliated nanocomposite is obtained.

Establishing A Uae Database Using Str Loci, Ibrahim Abdullah Ali Al-Housani

Theses

The analysis of DNA polymorphism has become an indispensable tool in forensic science and criminal cases. Today, the amplification of Short Tandem Repeat (STR) loci using PCR is the perfect method for typing biological evidence found at crime scenes. Forensic laboratories all over the world have been progressively expanding their databases for better discrimination among individuals and suspects of crimes.

The objective of this thesis was to analyze the DNA profile of native and non-native populations, and to study the similarities and dissimilarities among them. Blood samples were collected from three non-natives (Egyptian, Indian and Pakistani) and native populations from …

On The Number Of Embeddings Of Minimally Rigid Graphs, Ciprian Borcea, Ileana Streinu

Computer Science: Faculty Publications

Rigid frameworks in some Euclidean space are embedded graphs having a unique local realization (up to Euclidean motions) for the given edge lengths, although globally they may have several. We study the number of distinct planar embeddings of minimally rigid graphs with $n$ vertices. We show that, modulo planar rigid motions, this number is at most ${{2n-4}\choose {n-2}} \approx 4^n$. We also exhibit several families which realize lower bounds of the order of $2^n$, $2.21^n$ and $2.28^n$. For the upper bound we use techniques from complex algebraic geometry, based on the (projective) Cayley--Menger variety ${\it CM}^{2,n}(C)\subset P_{{{n}\choose {2}}-1}(C)$ over the …

Grassland Reserve Program, Environmental Assessment, Natural Resources Conservation Service, Farm Service Agency, United States Department Of Agriculture

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.

Microsatellite Variation In Red-Winged Blackbirds (Agelaius Phoeniceus), C. Lenney Williams, H.J. Homan, J.J. Johnston, G. M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Territorial male red-winged blackbirds from five locations in the United States and Canada were genotyped using a suite of six microsatellite loci. Each population possessed unique alleles, but numbers of alleles per locus (range = 7.3–8.8) and expected multilocus heterozygosities (range = 0.76–0.80) were similar in all populations. Significant overall allele frequency differences were detected between some population pairs, and some pairwise F_st values were significant (but small). However, F_st among populations, although significant, was also small (0.009). Despite revealing low levels of population structure, the high multilocus polymorphism indicates these loci will be valuable in the genetic …

Existence Of Solutions To A Hamiltonian System Without Convexity Condition On The Nonlinearity, Gregory S. Spradlin

Publications

We study a Hamiltonian system that has a superquadratic potential and is asymptotic to an autonomous system. In particular, we show the existence of a nontrivial solution homoclinic to zero. Many results of this type rely on a convexity condition on the nonlinearity, which makes the problem resemble in some sense the special case of homogeneous (power) nonlinearity. This paper replaces that condition with a different condition, which is automatically satisfied when the autonomous system is radially symmetric. Our proof employs variational and mountain-pass arguments. In some similar results requiring the convexity condition, solutions inhabit a submanifold homeomorphic to the …

The Thermal Degradation Of Nanocomposites That Contain An Oligomeric Ammonium Cation On The Clay, Shengpei Su, Charles A. Wilkie

Chemistry Faculty Research and Publications

The thermal degradation of polystyrene, high-impact polystyrene, ABS terpolymer, poly(methyl methacrylate), polypropylene and polyethylene nanocomposites has been studied using thermogravimetric analysis coupled to Fourier transform infrared spectroscopy, TGA/FT-IR. The nanocomposites that have been studied include immiscible, intercalated and exfoliated systems and the evolved gases do not depend upon the type of nanocomposite and are qualitatively similar to those of the virgin polymer. In the case of the styrenics, the presence of clay promotes the production of oligomer, rather than monomer. It is suggested that this change in evolved products may offer an explanation for why some polymers give large reduction …

Poly(Methyl Methacrylate), Polypropylene And Polyethylene Nanocomposite Formation By Melt Blending Using Novel Polymerically-Modified Clays, Shengpei Su, David D. Jiang, Charles A. Wilkie

Chemistry Faculty Research and Publications

Two new organically-modified clays that contain an oligomeric styrene or methacrylate have been prepared and used to produce nanocomposites of poly(methyl methacryate), polypropylene and polyethylene. Intercalated nanocomposites and, in some cases, exfoliated or mixed intercalated/exfoliated nanocomposites of all of these polymers have been produced by melt blending in a Brabender mixer. The use of the styrene-containing clay permits the direct blending of the clay with polypropylene, without the usual need for maleation, to produce the nanocomposites. The systems have all been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry and the measurement of mechanical properties. These novel …

Systems-Based Design Of Bi-Ligand Inhibitors Of Oxidoreductases: Filling The Chemical Proteomic Toolbox, Daniel S. Sem, Bonnie Bertolaet, Brian Baker, Edcon Chang, Aurora Demertrina Costache, Stephen Coutts, Qing Dong, Mark Hansen, Victor Hong, Xuemei Huang, Richard M. Jack, Richard Kho, Henk Lang, Chen-Ting Ma, David Meininger, Maurizio Pellacchia, Fabrice Pierre, Hugo Villar, Lin Yu

Chemistry Faculty Research and Publications

Genomics-driven growth in the number of enzymes of unknown function has created a need for better strategies to characterize them. Since enzyme inhibitors have traditionally served this purpose, we present here an efficient systems-based inhibitor design strategy, enabled by bioinformatic and NMR structural developments. First, we parse the oxidoreductase gene family into structural subfamilies termed pharmacofamilies, which share pharmacophore features in their cofactor binding sites. Then we identify a ligand for this site and use NMR-based binding site mapping (NMR SOLVE) to determine where to extend a combinatorial library, such that diversity elements are directed into the adjacent substrate site. …

Double Whammy: Collateral Consequences Of Conviction And Imprisonment For Sustainable Communities And The Environment, Avi Brisman

William & Mary Environmental Law and Policy Review

No abstract provided.

Influence Of The Hall Term On Kh Instability And Reconnection Inside Kh Vortices, K. Nykyri, A. Otto

Publications

The Kelvin-Helmholtz instability (KHI) in its nonlinear stage can develop small-scale filamentary field and current structures at the flank boundaries of the magnetosphere. It has been shown previously with MHD simulations that magnetic reconnection can occur inside these narrow current layers, resulting in plasma transport from the solar wind into the magnetosphere. During periods of northward IMF, this transport is sufficient to generate a cold, dense plasma sheet on time scales consistent with satellite observations. However, when the length scales of these narrow current layers approach the ion inertia scale, the MHD approximation is not valid anymore and the Hall …

Book Review: The Big Bang: A View From The 21st Century, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of The Big Bang : a View from the 21st Century by David M. Harland. Springer/Praxis, 2003 262p, 1-85233-713-3 $39.95.

Laser Induced Desorption Time Of Flight Mass Spectrometer Analysis Of Adsorbed Contaminants On Vacuum Ultraviolet Lithography Optic Materials, Susan D. Allen, Yamini Surpaneni

Publications

Adsorbed surface contaminants on optical elements absorb light energy in an optical lithography system and, if left unclean, will result in reduced wafer yield. In order to nondestructively analyze the surface adsorbate of different CaF2 samples, a laser induced desorption-Time of Flight Mass Spectrometer (LID-TOFMS) technique was developed. The main object of this technique is to investigate the surface composition of adsorbed contaminants as a function of position on the sample. An Er:YAG laser at 2.94 μm was used as the light source to induce desorption. Electron impact ionization was used to obtain ionization of desorbed molecules. The detection of …

The Biodiversity And Biogeochemistry Of Cryoconite Holes From Mcmurdo Dry Valley Glaciers, Antarctica, Dorota L. Porazinska, Andrew G. Fountain, Thomas H. Nylen, Martyn Tranter, Ross A. Virginia, Diana H. Wall

Geography Faculty Publications and Presentations

Once thought of as inert, ice has been increasingly recognized as a habitat suitable for life. The landscape of the MCMurdo Dry Valleys (MCM) of Antarctica is dominated by glaciers, and glacier melt is the primary water source for life in soils, streams, and lakes. The glaciers, despite their cold and lifeless appearance, offer functioning habitats for life. The major objective of this study was to examine biogeochemical characteristics of miniecosystems present in cryoconite holes and to determine links to other components (soils, streams, and lakes) of the dry valley landscape. We examined cryoconite holes from 5 glaciers spanning the …

Narrogin Townsite Test Pumping Results 2003, Louise Hopgood

Resource management technical reports

Test pumping of a production bore in Narrogin took place for 24 hours in August 2003. Data generated by the test pumping was analysed along with groundwater monitoring, climate and geological data. Laboratory analyses of water samples from the production bore indicate very high levels of salinity and hardness which may lead to severe scaling and corrosion of pumps, pipes and pipe fittings.

Finite Horizon Riemann Structures And Ergodicity, Victor J. Donnay, Charles Pugh

Mathematics Faculty Research and Scholarship

In this paper we show that any surface in R-3 can be modified by gluing on small 'focusing caps' so that its geodesic flow becomes ergodic. A new concept, finite horizon cap geometry, is what makes the construction work.