Physical Sciences and Mathematics Commons^™

Properties Of Z≥6 Galaxies In Cosmological Sph Simulations, Jason Jaacks

Undergraduate Research Opportunities Program (UROP)

Recent upgrades to the Hubble Space Telescope have given observers their deepest look into our Universe yet, seeing nearly 13 billion years into the past. This new observational data has presented those of us that use simulations to study the early Universe a benchmark opportunity to evaluate the ability of these codes to reproduce the photometric properties being observed. Establishing this agreement allows us to probe deeper into the physical properties such as mass, star formation histories and star formation rates of these early galaxies. This research lays the ground work for examining the contribution of primordial galaxies to the …

Chemical Weathering Of Serpentinite Rocks And Implications For Atmospheric Co2 Carbonation, Valerie Tu, Julie Baumeister, Elisabeth Hausrath

Undergraduate Research Opportunities Program (UROP)

No abstract provided.

Hydrostaticity Of Pressure Transmitting Medium Of 4:1 Methanol: Ethanol At High Pressure And Low Temperature, Christopher Salvo, Andrew Cornelius

Undergraduate Research Opportunities Program (UROP)

In high pressure physics a key element is the pressure transmitting medium. The purpose of this research is to study the hydrostatic limits of pressure transmitting media such as 4:1 Methanol: Ethanol and Silicone Fluid at low temperatures and high pressures.This will be done using a Merrill-Bassett diamond anvil cell (DAC) placed inside of a cryostat capable of reaching temperatures as low as 30 Kelvin for a range to 300 Kelvin. The hydrostaticity of 4:1 Methanol:Ethanol has been heavily studied at room temperature using the fluorescence of ruby by fitting the R1 and R2 lines to pseudo-Voigt functions. The full …

Potassium Chlorate Decomposition Under High Pressure, Harrison Ruiz, Michael G. Pravica, Martin Galley

Undergraduate Research Opportunities Program (UROP)

High pressure physics involves placing various substances under high pressure and observing changes in that substance. In this experiment this high amount of pressure is induced using a diamond anvil cell. A diamond anvil cell uses a metal gasket to hold the sample between two diamonds, which will press on the sample to reach high pressures. High pressures are reached with a moderate amount of force by exerting that force over a small area. Diamonds are used for the compression because of their hardness and ability to resist compression. The pressure being exerted on the sample using a diamond anvil …

Thin Film Optical Filter Fabrication And Characterization, Adam G. Hammouda, David P. Shelton

Undergraduate Research Opportunities Program (UROP)

Thin film coatings have a large number of applications. For example, one can eliminate unwanted reflection on a photographic lens or unwanted wavelengths of light in optics experimentation. The fabrication and characterization of films whose refractive indices can be arbitrarily modulated (‘Rugate Filters’) is an ongoing exploration in materials science1,2. Therefore, calibrating a process which can manufacture such films is a relevant pursuit in forwarding such explorations. Reactive magnetron sputter deposition is a commonly used technique for the productions of thin films3,4. This technique steadily flows reactive gas (RG) into a vacuum chamber in which an electric field has been …

Geochemistry Of Pyrite And Whole Rock Samples From The Getchell Carlin–Type Gold Deposit, Humboldt County, Nevada, Tim A. Howell, Jean S. Cline

Undergraduate Research Opportunities Program (UROP)

Carlin-type gold deposits were not recognized as a new major type of gold deposit until the 1960’s. The Getchell deposit, which is now known to be a Carlin-type gold deposit, was discovered in 1934 (Joralemon, 1951). This deposit is located in north central Nevada (Fig. 1). Much is known about the physical characteristics of Carlin-type gold deposits (Cline et al., 2005). An unusual characteristic of these deposits is that free gold is generally not present. Instead, gold occurs as sub-micrometer particles in the mineral pyrite or marcasite. The marcasite and pyrite that are gold bearing commonly occur as rims on …

Synthesis Of Bis-Styrylbenzene Derivatives Via Wittig-Horner Reaction, Joseph K. Wray, Tae Soo Jo, Pradip K. Browmik

Undergraduate Research Opportunities Program (UROP)

Alzheimer’s Disease is now one of the most common diseases affecting the elderly population. Recently, bis-styrylbenzene derivatives have been shown to reduce the formation of Beta-amyloid plaques in the brain which are profoundly correlated with this disease. Finding new biologically active compounds which can reduce or prevent Alzheimer’s Disease has drawn much attention over the past few decades. Georg Wittig, Nobel Prize Winner in Chemistry, 1979.

Undergraduate Research Opportunities Program 2010, University Of Nevada, Las Vegas

Undergraduate Research Opportunities Program (UROP)

The Undergraduate Research Opportunities Program (UROP) cultivates and supports research partnerships and invites undergraduates to work as the junior colleagues of faculty. The program offers the opportunity to work on cutting edge research—whether you join established research projects or pursue your own ideas. As participants, undergraduates engage in each phase of standard research activity: developing research plans, writing proposals, conducting research, analyzing data. and presenting research results in oral and written form. The projects take place over the summer, and research can be done in any academic department or interdisciplinary laboratory. Projects can last for an entire semester, and many …

Intelligent Software For Ecological Building Design, Jens G. Pohl, Hisham Assal, Kym J. Pohl

Collaborative Agent Design (CAD) Research Center

Building design is a complex process because of the number of elements and issues involved and the number of relationships that exist among them. Adding sustainability issues to the list increases the complexity of design by an order of magnitude. There is a need for computer assistance to manage the increased complexity of design and to provide intelligent collaboration in formulating acceptable design solutions. Software development technology today offers opportunities to design and build an intelligent software system environment that can serve as a reliable intelligent partner to the human designer.

In this paper the authors discuss the requirements for …

Preconference Proceedings On Advances In Adaptive Planning Capabilities, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

No abstract provided.

Existence Of Energy-Minimal Diffeomorphisms Between Doubly Connected Domains, Tadeusz Iwaniec, Ngin-Tee Koh, Leonid V. Kovalev, Jani Onninen

Mathematics - All Scholarship

The paper establishes the existence of homeomorphisms between two planar domains that minimize the Dirichlet energy. Specifically, among all homeomorphisms f : omega -> omega* between bounded doubly connected domains such that Mod (omega) < Mod (omega*) there exists, unique up to conformal authomorphisms of omega, an energy-minimal diffeomorphism. No boundary conditions are imposed on f. Although any energy-minimal diffeomorphism is harmonic, our results underline the major difference between the existence of harmonic diffeomorphisms and the existence of the energy-minimal diffeomorphisms. The existence of globally invertible energy-minimal mappings is of primary pursuit in the mathematical models of nonlinear elasticity and is also of interest in computer graphics.

Interview With Garrett Moon, The Commons Project, 2010 (Audio), Garrett Moon

All Sustainability History Project Oral Histories

Interview of Garrett Moon by Rayne Walter-Young at Portland State University on August 3rd, 2010.

The interview index is available for download.

A New Receiver Placement Scheme Using Delaunay Refinement-Based Triangulation, Mohammed Rana Basheer, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a sub-optimal solution to the receiver placement and number of receiver determination problem is introduced. to achieve this overall goal, first, localization error for a received signal strength indicator (RSSI)-Based N-receiver system localizing a transmitter is estimated. Subsequently, this estimator error along with the 2D-tessellation techniques such as Delaunay refinement are used to position candidate receivers not only to minimize their number needed to meet the location error threshold but also to reduce the dilution of localization accuracy due to the layout of receivers. Rigorous mathematical analysis indicates that the receiver count generated by our Delaunay Refinement-Based …

A New Adaptive Compression Scheme For Data Aggregation In Wireless Sensor Networks, Priya Kasirajan, Carl Larsen, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless sensor nodes typically have limited processing capabilities and are powered by batteries. the amount of energy expended in transmitting a single data bit would be several orders of magnitude higher when compared to the energy needed for a 32-bit computation. Thus, to maximize network lifetime, data transmissions should be minimized without losing vital information. in this paper, a novel adaptive compression scheme using nonlinear estimation theory is proposed for data aggregation. Satisfactory performance of the proposed compression scheme in the presence of noise, distortion, and quantization errors is demonstrated using Lyapunov approach. the proposed scheme is contrasted with existing …

Mutation Size Optimizes Speciation In An Evolutionary Model, Nathan Dees, Sonya Bahar

Physics Faculty Works

The role of mutation rate in optimizing key features of evolutionary dynamics has recently been investigated in various computational models. Here, we address the related question of how maximum mutation size affects the formation of species in a simple computational evolutionary model. We find that the number of species is maximized for intermediate values of a mutation size parameter μ; the result is observed for evolving organisms on a randomly changing landscape as well as in a version of the model where negative feedback exists between the local population size and the fitness provided by the landscape. The same result …

A Method To Implement Location Transparency In A Web Service Environment, Xiaoshan Pan, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Location transparency offers some significant benefits in the areas of middleware, Service-Oriented Architecture (SOA) and Cloud Computing. However, methods for achieving location transparency in a Web service environment are scarcely presented in the literature. This paper introduces such a method by describing a design and HTTP protocol-based implementation of location transparency. A number of benefits, including support for the creation of a virtual platform and increased mobility, availability and scalability of services, are elaborated. Two significant capabilities -performance-based load balancing and failover -are demonstrated as part of the experimental results.

On The Road To Intelligent Web Applications, Hisham Assal, Kym J. Pohl, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Increasing access to data sources on the Internet offers expanding opportunities for equipping intelligent applications with the content they require whether broad in scope or rich in detail. Although typically originating within the web in a semi-structured form, with the use of inference-based translation and analysis mechanisms such content can be transformed into useful information and ultimately into actionable knowledge. Service-Oriented Architecture (SOA) offers a platform for accessing the web as invocable resources and effectively incorporating multiple sources of data and capabilities on the Internet into enterprise applications. Adding inference capabilities to SOA-based applications not only aids in the translation …

Solving The Data Deluge Problem, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

The paper postulates that the information technology revolution that is commonly referred to as the Information Age is currently in a transition stage between data-processing and knowledge management that should be more aptly referred to as the Data Age. Symptoms of this transition stage are a data deluge problem that is evidenced by the inability of human computer-users to effectively analyze and draw useful conclusions from the overwhelming volume of data that is being collected, the increasing complexity of networked systems, and the acknowledged vulnerability of virtually all existing digital systems to cyber security threats.

The author suggests that the …

Bilinear Programming And Protein Structure Alignment, J. Cain, D. Kamenetsky, N. Lavine

Mathematical Sciences Technical Reports (MSTR)

Proteins are a primary functional component of organic life, and understanding their function is integral to many areas of research in biochemistry. The three-dimensional structure of a protein largely determines this function. Protein structure alignment compares the structure of a protein with known function to that of a protein with unknown function. A protein’s three-dimensional structure can be transformed through a smooth piecewise-linear sigmoid function to a real symmetric contact matrix that represents the functional significance of certain parts of the protein. We address the protein alignment problem as a minimization of the 2-norm difference of two proteins’ contact matrices. …

Heralded Single-Photon Partial Coherence, P. Ben Dixon, Gregory A. Howland, Mehul Malik, David J. Starling, R. W. Boyd, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We study transverse spatial coherence of approximately localized single-photon states. We demonstrate nonlocal control over single-photon spatial coherence via projective measurements of an entangled twin and provide a theoretical interpretation from quantum coherence theory. Our results show that the spatial coherence of a single-photon state behaves similarly to that of a classical optical field, although the coincidence measurement adds a degree of freedom.

Combined Measurement And Qcd Analysis Of The Inclusive E ±P Scattering Cross Sections At Hera, F. D. Aaron, H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, M. Aldaya Martin, C. Alexa, V. Andreev, S. Antonelli, P. Antonioli, A. Antonov, B. Antunovic, M. Arneodo, V. Aushev, O. Bachynska, S. Backovic, A. Baghdasaryan, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, E. Barrelet, W. Bartel, D. Bartsch, M. Basile, K. Begzsuren, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, Margarita C. K. Mattingly

Faculty Publications

A combination is presented of the inclusive deep inelastic cross sections measured by the H1 and ZEUS Collaborations in neutral and charged current unpolarised e±p scattering at HERA during the period 1994-2000. The data span six orders of magnitude in negative four-momentum-transfer squared, Q2, and in Bjorken x. The combination method used takes the correlations of systematic uncertainties into account, resulting in an improved accuracy. The combined data are the sole input in a NLO QCD analysis which determines a new set of parton distributions, HERAPDF1.0, with small experimental uncertainties. This set includes an estimate of the model and parametrisation …

Scraping Behavior In Male White-Tailed Deer As A Potential Means Of Transmitting Chronic Wasting Disease, Travis C. Kinsell

School of Natural Resources: Dissertations, Theses, and Student Research

Chronic wasting disease (CWD) has become a concern for wildlife managers and hunters across the United States. High prevalence of chronic wasting disease (CWD) in older male white-tailed deer (Odocoileus virginianus) suggests that sex-specific social behavior may contribute to the spread of the disease among males. Scraping is a marking behavior performed by male white-tailed deer during the rut in which a pawed depression and associated over-hanging branch are marked with saliva, glandular secretions, urine, and feces. We placed 71 and 35 motion-activated cameras on scrapes in DeSoto National Wildlife Refuge in western Nebraska and eastern Iowa from …

Steps Toward Butternut (Juglans Cinerea L.) Restoration, Sunshine L. Brosi

Doctoral Dissertations

Butternut (Juglans cinerea L.), a lesser-known relative of black walnut (Juglans nigra L.), is a native tree species beneficial for wildlife, valuable for timber, and part of the great diversity of species in the eastern forests of North America. Populations of butternut are being devastated by butternut canker disease, caused by the fungus Sirococcus clavigignenti-juglandacearum (V.M.G. Nair, Kostichka, & Kuntz), which is thought to be introduced to North America. The disease causes multiple branch and stem cankers that eventually girdle trees. Small population sizes, lack of sprouting, and shade intolerance exacerbates the disease and results in permanent losses of butternut …

Polymeric Loop Formation At Hard And Soft Interfaces, Earl Ashcraft

Doctoral Dissertations

Copolymers are used to increase the interfacial strength of immiscible components and suppress recombination of the minor phase by steric hindrance. The experiments conducted in these studies are designed to investigate in situ polymer loop formation at soft interfaces and functionalized nanotube surfaces. Block copolymers are the most effective type of copolymer for compatibilization because they extend perpendicular to the interface, allowing good entanglement with the homopolymer chains. Multiblock copolymers are more effective than diblock copolymers for strengthening the interface because they can cross the interface multiple times, forming “loops” in each phase that provide entanglement points for the homopolymer. …

Sources And Transport Pathways Of Fecal Bacteria And Pathogens To Aquifers In Rural Bangladesh, Peter S. K. Knappett

Doctoral Dissertations

During the 1980’s millions of households in Bangladesh switched from drinking surface water to private groundwater wells to reduce their exposure to fecal microorganisms. Sadly, this switch to shallow groundwater resulted in the largest example of drinking water poisoning in history, with approximately 100 million people exposed to high concentrations of naturally occurring Arsenic in the groundwater. Spatial distribution of Arsenic in the shallow aquifers tends to be patchy, so the most economical mitigation option has been lateral switching from high Arsenic wells to nearby low Arsenic wells. The recently developed Arsenic flushing conceptual model, which explains the spatial distribution …

Density Functional Calculation Of X-Ray Absorption Spectra Within The Core Hole Approximation: An Implementation In Nwchem, William Ben Carlen

Doctoral Dissertations

Density functional theory is used to calculate the core excitation spectra of titanium structures. Specifically, the core-hole approximation is used. In this scenario, the excitation energies of core electrons are calculated using the approximation that the core energy level be frozen throughout the relaxation process of the orbitals. This allows a more acurate determination of the resulting X-ray spectra. The method described has been implemented in an NWChem module.

Supported Aqueous-Phase Catalysis For Atom Transfer Radical Polymerization, Ravi Aggarwal

Doctoral Dissertations

Atom transfer radical polymerization (ATRP) which utilizes transition metal based catalysts is a versatile methodology for the synthesis of a wide spectrum of polymers with controlled architectures. However, high concentrations of soluble catalyst required in an ATRP process makes the final polymer colored and toxic. Thus, the catalyst removal/reduction/recycling remains a challenge in the field of ATRP. Supported catalysts on insoluble solids such as silica gel, polystyrene beads, etc. have been used in ATRP to facilitate the catalyst recovery and recycling. However, the ability of the supported catalysts to mediate a polymerization is substantially reduced due to their reduced mobility …

Surface And Subsurface Structures Of The Western Valley And Ridge In Tennessee And Geometry And Kinematics That Permit Reconstruction Of The Tennessee Salient, Southern Appalachians, Jennifer Kathleen Whisner

Doctoral Dissertations

The southern and central Appalachian foreland fold-thrust belt comprises a series of orogen -scale curves that extend from Alabama to New York. One of these is the Tennessee salient, a foreland-convex curve that extends from Cartersville, Georgia, to Roanoke, Virginia. Development of a kinematic model for deformation in the salient has been hindered by a paucity of penetrative deformation in this generally low temperature, low volume-loss portion of the orogen.

Industry seismic reflection lines provide greater resolution of subsurface geometry of both the basement surface and the overlying fold-thrust belt, confirming some previous interpretations and changing others. A series of …

Multidimensional Liquid Chromatography Separations, Jacob N. Fairchild

Doctoral Dissertations

Many mixtures important to research consist of hundreds or even thousands of individual components of interest. These types of mixtures are far too complex to separate by a single chromatographic dimension in any reasonable amount of time. However, if a multidimensional approach is used, where a complex mixture is separated by an initial dimension, simpler fractions of that separation are collected and each of those fractions are analyzed individually, highly complex mixtures can be resolved in relatively short amounts of time. This dissertation serves as a guide to multidimensional chromatography, in particular, two-dimension liquid chromatography. There are many aspects of …

Spatiotemporal Dynamics In A Lower Montane Tropical Rainforest, Robert Michael Lawton

Doctoral Dissertations

Disturbance in a forest’s canopy, whether caused by treefall, limbfall, landslide, or fire determines not only the distribution of well-lit patches at any given time, but also the ways in which the forest changes over time. In this dissertation, I use a 25 year record of treefall gap formation find a novel and highly patterned process of forest disturbance and regeneration, providing a local mechanism by examining the factors that influence the likelihood of treefall. I then develop a stochastic cellular automaton for disturbance and regeneration based on the analysis of this long term data set and illustrate the potential …