Physical Sciences and Mathematics Commons^™

Interaction Between Metal Fission Products And Triso Coating Materials, Clemens Heske

Fuels Campaign (TRP)

In this project the chemical bonding and interface formation of metal fission products with the coating materials used in TRISO fuel particles is investigated. The interface formation of Pd, Cs, and Ag with SiC and pyrolytic carbon is studied in detail. Using the SiC single crystals and TRISO coating materials as substrates, interfaces are prepared under controlled conditions in an ultra-high vacuum environment and are studied with a photoelectron spectroscopy, Auger electron spectroscopy, Inverse Photoemission, X-ray emission spectroscopy, and X-ray absorption spectroscopy. Recent additions to the experimental approach include microscopic techniques (Transmission Electron Microscopy, Scanning Tunneling Microscopy, Atomic Force Microscopy) …

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix, Kenneth Czerwinski

Fuels Campaign (TRP)

This project examines inert fuels containing ZrO₂ and MgO as the inert matrix, with the relative amount of MgO varied from 30% to 70% in ZrO₂. Reactor physics calculations are used to examine suitable quantities of burnable poisons from the candidate elements Gd, Er, or Hf with reactor grade Pu providing the fissile component, with up to 10% of ²³⁹Pu. Ceramics are synthesized and characterized based on the reactor physics results. The solubility of the fuel ceramics, in reactor conditions, reprocessing conditions, and repository conditions, are investigated in a manner to provide thermodynamic data necessary for …

University Of Nevada, Las Vegas Transmutation Research Program Annual Report Academic Year 2005-2006, Anthony Hechanova, Rebecca Arbour

Transmutation Research Program Reports (TRP)

It is my pleasure to present the UNLV Transmutation Research Program’s fifth annual report that highlights the academic year 2005 – 2006. Supporting this document are the many technical reports and scientific papers that have been generated over the past five years.

In the fifth year of our program, we saw amazing growth in the Radiochemistry Ph.D. program with a total of 12 students in the second year of the program (twice the number we anticipated in the program proposal). In the back of this issue, under Infrastructure Augmentation, you will find some news about the new academic programs sponsored …

Restoration Of Frequency-Dependent Depression Of The H-Reflex By Passive Exercise In Spinal Rats, N. B. Reese, R. D. Skinner, D. Mitchell, C. C. Yates, Christina B. Cooley, T. S. Kiser, E. E. García-Rill

Chemistry Faculty Research

Hyper-reflexia, measured as a decrease of low frequency-dependent depression of the H-reflex, is known to occur in both humans and animals after spinal cord injury (SCI). Previous studies have shown that passive exercise for 3 months could be used to restore low frequency-dependent depression of the H-reflex after SCI. To determine the effects of various periods of time on the ability of passive exercise to restore low frequency-dependent depression of the H-reflex. Spinal Cord Injury Mobilization Program of the Center for Translational Neuroscience, the research arm of the Jackson T Stephens Spine and Neuroscience Institute, Little Rock, AR, USA. Adult …

Spectroscopic And Thermodynamic Analysis Of Co Rebinding And Photodissociation From Fe (Ii) Lpo, Dustin Michael Lockney

Theses, Dissertations and Capstones

Lactoperoxidase (LPO) is a heme peroxidase found in tears, milk, saliva, and cervical fluids that has bactericidal activity. The bactericidal nature of LPO is due to its ability to oxidize halides and pseudohalides in the presence of H2O2. Full understanding of the catalytic cycle of LPO requires detailed characterization of the mechanism of ligand binding to the enzyme active site. This includes a dynamic and energetic description of conformational changes associated with heme-ligand interactions. Photoacoustic calorimetry is applied to determine the kinetics and magnitude of reaction volume and enthalpy changes for CO dissociation from CO-LPO. Time-resolved absorption spectroscopy was used …

Scanning Probe Microscopy And Oxidation Of Silicon At Breakdown Voltages, Thabo Gcwabaza

Theses, Dissertations and Capstones

The growing importance of Scanning Probe Microscopy (SPM) as a tool for nanofabrication is opening many avenues in lithography nano-science. One type of Scanning Probe Lithography involves electrochemistry at the tip/substrate interface. Atomic Force Microscopy (AFM) with conductive tips and substrates was used in our study to both pattern and image those patterns on silicon substrates. Our long-term objective is to design and fabricate micron-scale patterns of nanometer sized spots on silicon chips that can serve as attachment sites for DNA based nano-arrays. In order to fabricate such substrates a study of the underlying electrochemistry was required. A most promising …

Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol

Faculty Publications, Biological Sciences

Three mammalian nuclear lamin proteins, lamin B1, lamin B2 and the lamin A precursor, prelamin A, undergo canonical farnesylation and processing at CAAX motifs. In the case of prelamin A, there is an additional farnesylation-dependent endoproteolysis, which is defective in two congenital diseases: Hutchinson-Gilford progeria (HGPS) and restrictive dermopathy (RD). These two diseases arise respectively from defects in the prelamin A substrate and the enzyme (ZmpSte24) that processes it. Recent work has shed light on the roles of the lamin proteins and the enzymes involved in their farnesylation-dependent maturation. Other experimental work, including mouse model studies, have examined the possibility …

Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou

Faculty Publications, Biological Sciences

The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their …

Nmr Investigations Of Natural Organic Matter In Forest Ecosystems, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Preparation Of Some Substituted Terephthalic Acids, Susanna Branion, Vladimir Benin

Chemistry Faculty Publications

We report in detail the preparation of two substituted terephthalic acids: 2‐sulfomethylterephthalic acid (1) and 2‐phosphonoterephthalic acid (2). Efficient, short syntheses have been developed for both compounds. They are potentially useful monomers for construction of acid‐pendant polymer chains.

Preparation, Characterization And Dft Studies Of Some New N-Nitrosocarbamates And N-Nitrosoureas, Ragavan Narayanan, Helene Hedian, Eric Shamo, Vladimir Benin

Chemistry Faculty Publications

We are presenting the preparation, characterization and density functional theory (DFT) studies {B3LYP/6-31+G(d)) of several reiated classes of N-nitrosocarbamates and N-nitrosoureas. The iong-range goal is the design and preparation of compounds, which would undergo photochemical or hydrolytic decomposition, to yield stabilized cyclic cations that can serve as alkylating agents at various nucleophilic centers, including DNA bases.

Magnetic Order In The Quasi-One-Dimensional Spin-1/2 Molecular Chain Compound Copper Pyrazine Dinitrate, T Lancaster, S J. Blundell, M L. Brooks, P J. Baker, F L. Pratt, Jamie L. Manson, C P. Landee, C Baines

Chemistry and Biochemistry Faculty Publications

We present evidence of magnetic order in the quasi-one-dimensional spin-1/2 molecular chain compound, copper pyrazine dinitrate Cu(C4H4N2)(NO3)(2). Zero field muon-spin relaxation measurements made at dilution refrigerator temperatures show oscillations in the measured asymmetry characteristic of a quasistatic magnetic field at the muon sites. Our measurements provide convincing evidence for long-range magnetic order below a temperature T-N=107(1) mK. This leads to an estimate of the interchain coupling constant of vertical bar J'vertical bar/k(B)=0.046 K and to a ratio of vertical bar J'/J vertical bar=4.4x10(-3).

Ecoscale, A Semi-Quantitative Tool To Select An Organic Preparation Based On Economical And Ecological Parameters, Koen Van Aken, Lucjan Strekowski, Luc Patiny

Chemistry Faculty Publications

A novel post-synthesis analysis tool is presented which evaluates quality of the organic preparation based on yield, cost, safety, conditions and ease of workup/purification. The proposed approach is based on assigning a range of penalty points to these parameters. This semi-quantitative analysis can easily be modified by other synthetic chemists who may feel that some parameters should be assigned different relative penalty points. It is a powerful tool to compare several preparations of the same product based on safety, economical and ecological features.

Ventrolateral Prefrontal Cortex Activation And Attentional Bias In Response To Angry Faces In Adolescents With Generalized Anxiety Disorder, Christopher Monk, Eric E. Nelson, Erin B. Mcclure, Karin Mogg, Brendan P. Bradley, Ellen Leibenluft, James R. Blair, Geng Chen, Dennis S. Charney, Monique Ernst, Daniel S. Pine

Chemistry Faculty Publications

Objective: While adolescent anxiety disorders represent prevalent, debilitating conditions, few studies explore their brain physiology. Using event-related functional MRI (fMRI) and a behavioral measure of attention to angry faces, we evaluated differences in response between healthy adolescents and adolescents with generalized anxiety disorder (GAD). Method: In the primary trials of interest, 18 adolescents with GAD and 15 comparisons of equivalent age/gender/IQ viewed angry/neutral face pairs during fMRI acquisition. Following the presentation of each face pair, subjects pressed a button to a probe that was either on the same (congruent) or opposite (incongruent) side as the angry face. Reaction time differences …

Simplified Low Copy Number Dna Analysis By Post Pcr Purification, Pamela Smith

Electronic Theses and Dissertations

Frequently evidentiary items contain an insufficient quantity of DNA to obtain complete or even partial DNA profiles using standard forensic gentotyping techniques. Here, various methods of post PCR purification were evaluated for their effects on the sensitivity of fluophore-based allelic detection. A method of post PCR purification is described which increases the sensitivity of standard 28 cycle PCR such that low copy number DNA templates (<100 pg DNA) can be analyzed. Full profiles were consistently obtained with as little as 20 pg template DNA without increased cycle number. In mock case type samples with dermal ridge fingerprints, genetic profiles were obtained by amplification with 28 cycles followed by post-PCR purification whereas no profiles were obtained without purification of the PCR product. Allele drop-out, increased stutter, and contamination (allele drop-in) typical of LCN analysis were observed. A single incident of contamination was observed in a reagent blank (not duplicated upon re-amplification) however, no contamination was observed in negative amplification controls.

A Minimum-Impact Method For Measuring Corrosion Rate Of Steel-Hulled Shipwrecks In Seawater, Matthew A. Russell, David L. Conlin, Larry E. Murphy, Donald L. Johnson, Brent M. Wilson, James D. Carr

Chemistry Department: Faculty Publications

Current research on USS Arizona is focused on a minimum-impact technique for calculating corrosion rate of the battleship’s steel hull by analysing physical and chemical properties of marine encrustation covering the exposed hull. An equation is derived that allows concretion thickness, density, and total iron content to be used to calculate corrosion rate of steel hull plate.

Properties Of New York/New Jersey Harbor Sediments, K. W. Jones, Huan Feng, E. A. Stren, U. Neuhäusler, J. Osán, N. Marinkovic, Z. Song

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Sediments found in waterways around the world may contain toxic compounds of anthropogeilic origin that can harm the environment and human health. As a result, it is often necessary to remove them and find disposal methods that are environmentally and economically acceptable. Here, we report on results obtained in an experimental program to characterize the nature of the sediment contamination. The objective was to gain a better understanding of the properties of the sediments to develop better methods for understanding the fate and transport of the contaminants and for improving methods for their removal from the sediments. Our investigations made …

Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol

Michael Sinensky

Three mammalian nuclear lamin proteins, lamin B1, lamin B2 and the lamin A precursor, prelamin A, undergo canonical farnesylation and processing at CAAX motifs. In the case of prelamin A, there is an additional farnesylation-dependent endoproteolysis, which is defective in two congenital diseases: Hutchinson-Gilford progeria (HGPS) and restrictive dermopathy (RD). These two diseases arise respectively from defects in the prelamin A substrate and the enzyme (ZmpSte24) that processes it. Recent work has shed light on the roles of the lamin proteins and the enzymes involved in their farnesylation-dependent maturation. Other experimental work, including mouse model studies, have examined the possibility …

Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou

Michael Sinensky

The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their …

Synthesis And Analysis Of An Α-Amylase Inhibitor And An Antimicrobial Peptide, Brahmlin Kaur Sethi

Senior Honors Theses and Projects

Abstract 1: α-Amylase is an important enzyme in the body responsible for hydrolyzing many polysaccharides such as dietary starch. Inhibition of this enzyme could be extremely beneficial in diabetic patients because it could lower the glucose levels in the blood. Our objective is to synthesize a small analog of a natural α-amylase inhibitor, Tendamistat. This molecule has 15-22 residue segment that are critical for its activity. The peptide was synthesized, cleaved, purified, analyzed, and an enzyme assay was run. Michaelis Menton and Lineweaver-Burk plots were constructed to determine the V_max, K_m, and K_i for each …

A Taxonomy Of Teleology: Phillip Johnson, The Intelligent Design Community, And Young-Earth Creationism, Marcus R. Ross, P. A. Nelson

Faculty Publications and Presentations

No abstract provided.

Surface Analysis Of A Black Coating From Little Lost River, Reshmi Perumplavil

Master's Theses and Doctoral Dissertations

A black coating of unknown origin obscures the pictographs in Little Lost River Cave, Idaho. We utilized x-ray photoelectron spectroscopy (XPS) to characterize the outermost surface of the black coating to understand how it was formed. Carbon and oxygen predominated in the XP spectra, whereas nitrogen was detected at varying levels in different samples. High-resolution carbon 1s XP spectra showed that carbon was present in at least three different forms: hydrocarbon C, carbonyl C, and carbonate C/ amide C. The N 1s peak was observed at ~399-400 eV binding energy, which is usually attributed to aromatic or amide N. The …

Nanodot-Based Organic Memory Devices, Zhengchun Liu

Doctoral Dissertations

In this study, resistor-type, diode-type, and transistor-type organic memory devices were investigated, aiming at the low-cost plastic integrated circuit applications. A series of solution-processing techniques including spin-coating, inkjet printing, and self-assembly were employed to fabricate these devices.

The organic resistive memory device is based on a novel molecular complex film composed of tetracyanoquinodimethane (TCNQ) and a soluble methanofullerene derivative [6,6]-phenyl C61-butyric acid methyl ester (PCBM). It has an Al/molecules/Al sandwich structure. The molecular layer was formed by spin-coating technique instead of expensive vacuum deposition method. The current-voltage characteristics show that the device switches from the initial 'low' conduction state to …

2,2′,3,3′-Tetra­Methyl-6,6′-Biquinoxaline, Ralph N. Salvatore, Jorden P. Kass, Ricky J. Paul Gibson, Cesar H. Zambrano, Robert D. Pike, Eric E. Dueno

Arts & Sciences Articles

The molecule of the title compound, C20H18N4, has twofold rotational symmetry. Each aromatic ring of the fused quinoxaline ring system is skewed from the other by 4.93 (7)°. The two quinoxaline units make a dihedral angle of 43.52 (2)°

Interaction-Induced Dipole Moment Of The Ar–H2 Dimer: Dependence On The H2 Bond Length, Robert J. Hinde

Chemistry Publications and Other Works

We present ab initio calculations of the interaction-induced dipole moment of the Ar–H₂ van der Waals dimer. The primary focus of our calculations is on the H₂ bond length dependence of the dipole moment, which determines the intensities of both the collision-induced H₂ = 1 ← 0 fundamental band in gaseous Ar–H₂ mixtures and the dopant-induced H₂ = 1 ← 0 absorption feature in Ar-doped solid H₂ matrices. Our calculations employ large atom-centered basis sets, diffuse bond functions positioned between the two monomers, and a coupled cluster treatment of valence electron correlation; core-valence correlation …

Negative Impact Of Noise On The Principal Component Analysis Of Nmr Data, Steven M. Halouska, Robert Powers

Chemistry Department: Faculty Publications

Principal component analysis (PCA) is routinely applied to the study of NMR based metabolomic data. PCA is used to simplify the examination of complex metabolite mixtures obtained from biological samples that may be composed of hundreds or thousands of chemical components. PCA is primarily used to identify relative changes in the concentration of metabolites to identify trends or characteristics within the NMR data that permits discrimination between various samples that differ in their source or treatment. A common concern with PCA of NMR data is the potential over emphasis of small changes in high concentration metabolites that would over-shadow signifi …

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 6, September 2004, Gary A. Bishop, Daniel A. Burgard, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In West Los Angeles: Year 4, October 2005, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

The Weekend Effect: The Science Suggests That We Are Embarking On An Expensive Policy Which Will Harm The Environment {Presentation}, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Tunneling Through Weak Interactions:  Comparison Of Through-Space-, H-Bond-, And Through-Bond-Mediated Tunneling, Westin Kurlancheek '03, Robert J. Cave

All HMC Faculty Publications and Research

Results from ab initio electronic structure theory calculations on model systems allow for the detailed comparison of tunneling through covalently bonded contacts, hydrogen bonds, and van der Waals contacts. Considerable geometrical sensitivity as well as an exponential distance dependence of the tunneling is observed for tunneling through various nonbonded contacts. However, the fundamental result from the present study is that at most a modest difference is observed between tunneling mediated by H-bonds and tunneling mediated by van der Waals contacts at typical distances for each type of interaction. These results are considered in relation to the pathways model of Beratan …