Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 10 of 10
Full-Text Articles in Physical Sciences and Mathematics
Γ-Aminobutyric Acid, Catecholamine And Indoleamine Determinations From The Same Brain Region By High-Performance Liquid Chromatography With Electrochemical Detection., T. Champney, W. Hanneman, Michael Nichols
Γ-Aminobutyric Acid, Catecholamine And Indoleamine Determinations From The Same Brain Region By High-Performance Liquid Chromatography With Electrochemical Detection., T. Champney, W. Hanneman, Michael Nichols
Michael A Nichols
A new procedure for the measurement of γ-aminobutyric acid, norepinephrine, dopamine, serotonin and 5-hydroxyindoleacetic acid from the same brain region was developed. In general, two separate high-performance liquid chromatographic runs were performed, one for the γ-aminobutyric acid determination and one for the determination of the monoamines. The electrochemical detection of γ-aminobutyric acid was determined by a new procedure that utilized a small aliquot of the brain sample prepared for monoamine measurement. This assay was linear and parallel between 6 and 200 ng per 20-μl injection with 5-aminovaleric acid utilized as an internal standard. Inter-assay variability averaged 5% throughout the assay …
Work-Function Anisotropies As An Origin Of Long-Range Surface Forces, Nancy Burnham, R Colton, H Pollock
Work-Function Anisotropies As An Origin Of Long-Range Surface Forces, Nancy Burnham, R Colton, H Pollock
Nancy A. Burnham
Unusual effects noticed in previous force microscopy data are explained by a model based on work-function anisotropies and their associated patch charges. Measurable forces between macroscopic bodies can be due to the interaction of patch charges, with important consequences in the fields of surface forces, contact mechanics, adhesion, Schottky barriers, and the surface properties of insulators.
The Elastic Moduli Of A Sheet Containing Circular Holes, Anthony Day, K. Snyder, E. Garboczi, M. Thorpe
The Elastic Moduli Of A Sheet Containing Circular Holes, Anthony Day, K. Snyder, E. Garboczi, M. Thorpe
Anthony Roy Day
We apply computer simulation techniques to obtain the clastic moduli of a matrix containing circular holes. As the area fraction of holes increases, the Young's modulus of the composite decreases from E0 until it eventually vanishes at the percolation threshold. We study three distinct geometries: (a) periodically centered circular holes on a honeycomb lattice, (b) periodically centered circular holes on a triangular lattice, and (c) randomly centered circular holes. All three cases have the same dilute limit that can be calculated exactly. By examining the narrow necks between adjacent circles, we have calculated the critical behavior for the regular cases …
Quark-Antiquark Condensates In Strong Magnetic Fields, Alec Schramm, Berndt Muller, Stefan Schramm
Quark-Antiquark Condensates In Strong Magnetic Fields, Alec Schramm, Berndt Muller, Stefan Schramm
Alec J Schramm
We discuss the effect of large external magnetic fields on the QCD vacuum structure. We show that the deformed vacuum leads to substantial changes in the hadronic spectrum.
W Boson Condensation In P-P Collisions?, Alec Schramm, Stefan Schramm, Berndt Muller
W Boson Condensation In P-P Collisions?, Alec Schramm, Stefan Schramm, Berndt Muller
Alec J Schramm
We address the question of whether W+/- boson condensation can occur in high-energy collisions.
Displacement, Velocity, And Frames Of Reference: Phenomenographic Studies Of Students’ Understanding And Some Implications For Teaching And Assessment, John Bowden, Gloria Dall'alba, Elaine Martin, D Laurillard, Ference Marton, Geoff Masters, Paul Ramsden, Andrew Stephanou, E Walsh
Displacement, Velocity, And Frames Of Reference: Phenomenographic Studies Of Students’ Understanding And Some Implications For Teaching And Assessment, John Bowden, Gloria Dall'alba, Elaine Martin, D Laurillard, Ference Marton, Geoff Masters, Paul Ramsden, Andrew Stephanou, E Walsh
Prof Geoff Masters AO
Student understanding of fundamental concepts in kinematics has been explored using the phenomenographic research method. University and high schoolphysics students were interviewed and their understandings of displacement, velocity, and frames of reference have been analyzed in particular problem contexts. Descriptions of the different ways students understand the concepts have been developed and relations between the different levels of understanding have been identified. The data highlight the contextual nature of learning and the need for teachers to focus on the nature of student understanding in specific contexts using questions that require qualitative explanation by students. In particular, it is demonstrated that …
A High Yield Microscale Enzymatic Synthesis And Purification Of 14c‐Labeled Nicotinamide Adenine Dinucleotide Phosphate (Nadp+), Andre Ronneberg, Gordon Metz, Richard Weld, Peter Roffey, Chris Craney
A High Yield Microscale Enzymatic Synthesis And Purification Of 14c‐Labeled Nicotinamide Adenine Dinucleotide Phosphate (Nadp+), Andre Ronneberg, Gordon Metz, Richard Weld, Peter Roffey, Chris Craney
Chris L. Craney
Uniformly labeled (U) 14C nicotinamide adenine dinucleotide phosphate (NADP+) was synthesized by phosphorylating [U-14C]nicotinamide adenine dinucleotide (NAD+) in the presence of immobilized NAD+ kinase. The 15 μCi (600 μL) synthesis consistently achieved yields between 80% and radiochemical purities greater than 95%. The [U-14C]NADP+ was purified by high performance anion-exchange chromatography using a gradient elution of ammonium bicarbonate. This procedure may be applicable to the synthesis of other charged, UV-absorbing products of enzyme-catalyzed reactions.
The Logic Of Unbalanced Subobjects In A Category With Two Closed Structures, Lawrence Stout
The Logic Of Unbalanced Subobjects In A Category With Two Closed Structures, Lawrence Stout
Lawrence N. Stout
No abstract provided.
Asymptotic Behavior Of Solutions Of A Linear Second Order Difference Equation, William F. Trench
Asymptotic Behavior Of Solutions Of A Linear Second Order Difference Equation, William F. Trench
William F. Trench
No abstract provided.
Mild Integrability Conditions For Global Solutions Of An Elliptic Equation, William F. Trench
Mild Integrability Conditions For Global Solutions Of An Elliptic Equation, William F. Trench
William F. Trench
No abstract provided.