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Probing Anomalous Structural Features in Polypurine Tract-Containing RNA-DNA Hybrids with Neomycin B

July 28, 2009

Author(s)

Robert G. Brinson, Kevin Turner, Hye Y. Yi-Brunozzi, Stuart F. Le Grice, Daniele Fabris, John P. Marino

During (-)-strand DNA synthesis in retroviruses and Saccharomyces cerevisiae LTR-retrotransposons, a purine rich region of the RNA template, known as the polypurine tract (PPT) is resistant to RNase H-mediated hydrolysis and subsequently serves as a primer

Study of Azeotrope Phase Equilibrium with the Advanced Distillation Curve Approach

July 15, 2009

Author(s)

Amelia Hadler, Lisa S. Ott, Thomas J. Bruno

Azeotrope mixtures are among the most fascinating, and at the same time the most complicated manifestations of phase equilibrium. They are also a critical aspect of many industrial processes and products. Indeed, with the current interest in alcohol

Composition-Explicit Distillation Curves for Mixtures of Diesel Fuel with Dimethyl Carbonate and Diethyl Carbonate

July 14, 2009

Author(s)

Thomas J. Bruno, Arron Wolk, Alexander Naydich, Marcia L. Huber

We have recently introduced several important improvements in the measurement of distillation curves of complex fluids. The modifications to the classical measurement provide for (1) a composition explicit data channel for each distillate fraction (for

Purity determination as needed for the realisation of primary standards for elemental determination - status of international comparability

July 9, 2009

Author(s)

Gregory C. Turk, Heinrich Kipphardt, Ralf Matschat, Jochen Vogl, Tamara Gusarova, Michael Czerwensky, Hans-Joachim Heinrich, Akiharu Hioki, Leonid A. Konopelko, Brad Methven, Tsutomu Miura, Ole Petersen, Gundel Riebe, Ralph Sturgeon, Lee L. Yu

Within the National Metrology Institutes (NMIs) and designated laboratories, an interlaboratory comparison, CCQM-P107, was conducted to verify the degree of international comparability concerning the results of purity analysis. The mass fractions of Ag, Bi

Detecting Chemical Hazards with Temperature-Programmed Microsensors: Overcoming Analytical Problems of Increasing Complexity by Utilizing Multi-Dimensional Databases

July 6, 2009

Author(s)

Douglas C. Meier, Baranidharan Raman, Stephen Semancik

Complex analytical problems, such as detecting trace quantities of hazardous chemicals in ambient environments composed of varying levels of humidity and vapors of benign products, require solutions that most effectively extract the relevant information

A Volcano Curve: Optimizing Methanol Electro-oxidation on Pt decorated Ru Nanoparticles

June 26, 2009

Author(s)

Christopher D. Zangmeister, Savelas A. Rabb, Du Bingchen, YuYe Tong

Controlled Pt adlayers were deposited on commercial Ru nanoparticles (NPs) using an industrially scalable one-pot ethylene glycol (EG) reduction based method and were characterized by X-ray diffraction (XRD), electrochemical (EC) CO stripping voltammetry

A Comparison of the Hypersonic Vehicle Fuel JP-7 to the Rocket Propellants RP-1 and RP-2 Using the Advanced Distillation Curve Method

June 15, 2009

Author(s)

Tara Lovestead, Thomas J. Bruno

JP-7 is a hydrocarbon-based kerosene fraction with a low volatility and high thermal stability. JP-7 was developed in the 1950s to meet the more stringent requirements necessary for the development of high-altitude reconnaissance planes that fly at speeds

Comparison of Clinical Methods with Isotope Dilution ICP-MS for the New Standard Reference Material 955c Lead In Caprine Blood

May 26, 2009

Author(s)

Karen E. Murphy, Thomas W. Vetter, Gregory C. Turk, Christopher D. Palmer, Miles E. Lewis, Ciaran M. Geraghty, Patrick J. Parsons, William F. Guthrie

The National Institute of Standards and Technology (NIST) has developed Standard Reference Material (SRM) 955c, a new caprine-based, four-level blood standard with certified blood lead levels (BLLs) ranging from 0.4 µg/dL (0.02 µmol/L) Pb to 45 µg/dL (2.17

Loss of Odor Through Conjugation, Suppression and Cross-Adaptation: How One Plus One Can Sometimes Equal Zero

May 19, 2009

Author(s)

Thomas J. Bruno

Since the days of the alchemist, the observation that some substances have a smell while others do not has been a source of fascination. The sense of smell, or olfaction, is our least developed and least understood sense, however it is important for many

Progress in Quantitative Surface Analysis by X-ray Photoelectron Spectroscopy: Current Status and Perspectives

May 14, 2009

Author(s)

Cedric J. Powell, Aleksander Jablonski

We give a survey of information needed for quantitative surface analyses by X-ray photoelectron spectroscopy (XPS). We describe four terms (the inelastic mean free path, the effective attenuation length, the mean escape depth, and the information depth)

Potential Primary Measurement Tool for the Quantification of DNA

May 1, 2009

Author(s)

Ryan G. Brennan, Savelas A. Rabb, Marcia J. Holden, Michael R. Winchester

An automated sample introduction system, utilizing a demountable direct injection high efficiency nebulizer (d DIHEN), is successfully incorporated for the first time with an inductively coupled plasma optical emission spectrometer (ICP-OES) for the

Enthalpy of Solution and Kovats Retention Indices for Nitroaromatic Compounds on Stationary Phases using Gas Chromatography

April 30, 2009

Author(s)

Jeffrey A. Caufield, Thomas J. Bruno, Keith Miller

Worldwide terrorism has recently resulted in increased efforts to detect and identify explosive residues. Availability of experimentally determined thermochemical data for explosive compounds and their degradation products are limited, however. Gas

Analysis of Fuel Ethanol Plant Liquor with the Composition Explicit Distillation Curve Method

April 16, 2009

Author(s)

Thomas J. Bruno, Arron Wolk, Alexander Naydich

While the use of ethanol and ethanol blends as motor fuels dates back to the earliest vehicles, ethanol has recently received extraordinary attention as a renewable liquid fuel. In the United States, the application of this fluid is mainly as an additive

Study of Azeotropic Mixtures with the Advanced Distillation Curve Approach

April 11, 2009

Author(s)

Amelia Hadler, Lisa S. Ott, Thomas J. Bruno

Classical methods for the study of complex fluid phase behavior include static and dynamic equilibrium cells that usually require vapor and liquid recirculation. These are sophisticated, costly apparatus that require highly trained operators, usually

T7-Based Linear Amplification of Low Concentration mRNA Samples using Beads and Microfluidics for Global Gene Expression Measurements

April 7, 2009

Author(s)

Jason G. Kralj, Audrey Player, Hope Sedrick, Matt S. Munson, David Petersen, Samuel P. Forry, Paul Meltzer, Ernest Kawasaki, Laurie E. Locascio

We show single-cell level linear amplification of gene expression libraries immobilized on a microfluidic packed bed. This is a critical step in the Eberwine process, which is used to amplify messenger RNA (mRNA) for gene expression profiling. Microarray

Evaluation of Oral Fluid Testing Devices

April 1, 2009

Author(s)

Lorna T. Sniegoski, Jocelyn L. Prendergast, Michael J. Welch, Alim A. Fatah, M Gackstetter, R. Q. Thompson

Several point-of-collection (POC) devices for detection of drugs of abuse in oral fluid were studied. The ability of the devices to meet the manufacturers' claims and their practical application to detection of drugs of abuse at low concentrations in oral

Polymerization Stress Development in Dental Composites: Effect of Cavity Design Factor

March 13, 2009

Author(s)

Joseph M. Antonucci, Anthony A. Giuseppetti, Justin N. O'Donnell, Gary E. Schumacher, Drago Skrtic

Objective: To assess the effect of the cavity design factor (C-factor) on polymerization stress development (PSD) in resin composites. Methods: An experimental resin (BT resin) was prepared, which contained 2,2-bis[p-(2 hydroxy-3 -methacryloxypropoxy

Composition-Explicit Distillation Curves for Mixtures of Gasoline with Four-Carbon Alcohols (Butanols)

March 9, 2009

Author(s)

Thomas J. Bruno, Arron Wolk, Alexander Naydich

Interest in the domestic production of bio-derived fuels, sparked by the high cost of petroleum crude oil, has lead to consideration of fluids to replace or extend conventional petroleum derived fuels. While ethanol as a gasoline extender has received a

Ionic Hydrogen bond Networks and Ion Solvation 1. An Efficient Monte Carlo / Quantum Mechanical Method for Structural Search and Energy Computation: Ammonium / Water

February 25, 2009

Author(s)

Yi-Lei Zhao, Michael Mautner, Carlos A. Gonzalez

Hydrogen bond networks about solvated ions can form many alternative structures, requiring extensive conformational searches with accurate but affordable energy computation. Combining Monte Carlo searches with the OPLS-AA force field plus geometry

Kinetic Barriers of H-Atom Transfer Reactions in Alkyl, Allylic, and Oxoallylic Radicals, as Calculated by Composite Ab Initio Methods

February 18, 2009

Author(s)

Carrigan J. Hayes, Donald R. Burgess Jr.

Composite ab initio and density functional theory (DFT) methods were used to explore internal hydrogen-atom transfers in a variety of primary, secondary, and tertiary alkyl and functionalized radicals with implications for combustion environments. The

Revised d 34 S Reference Values for IAEA Sulfur Isotope Reference Materials S-2 and S-3

February 7, 2009

Author(s)

Jacqueline L. Mann, Robert D. Vocke Jr., William R. Kelly

Revised δ 34S reference values with associated expanded uncertainties (95% confidence interval (C.I.)) are presented for he sulfur isotope reference materials IAEA-S-2 (22.62 ±0.16{0/00}). These revised values are determined using two relative-difference

SEABIRD TISSUE ARCHIVAL AND MONITORING PROJECT: Egg Collections and Analytical Results for 2002-2005

February 5, 2009

Author(s)

Stacy S. Schuur, Paul R. Becker, Russell D. Day, Michael B. Ellisor, Aurore Guichard, Amanda J. Moors, David Point, Rebecca S. Pugh, David G. Roseneau

The Seabird Tissue Archival and Monitoring Project (STAMP) has continued to collect and bank murre and gull eggs to obtain new information on chlorinated pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, mercury, and organotin

Thermal Decomposition Kinetics of Propylcyclohexane

January 21, 2009

Author(s)

Jason A. Widegren, Thomas J. Bruno

As part of a large-scale thermophysical property measurement project, the decomposition kinetics of propylcyclohexane was investigated. Decomposition reactions were performed at 375, 400, 425, and 450 °C in stainless steel ampoule reactors. At each

Striped Domains at the Pentacene:C 60 Interface

January 12, 2009

Author(s)

Dan B. Dougherty, W Jin, J Cullen, J Reutt-Robey, Steven W. Robey

STM observations of the initial growth stages of the first layer of pentacene on a monolayer film of C60 on Ag(111) are presented. Pentacene films nucleate and grow with molecules standing up at the Pentacene:C60 interface similar to the well known thin

Inducing analytical orthogonality in tungsten oxide-based microsensors using materials structure and dynamic temperature control

January 4, 2009

Author(s)

Kurt D. Benkstein, Baranidharan Raman, David L. Lahr, John E. Bonevich, Stephen Semancik