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4. Nuclear magnetic resonance of J-coupled quadrupolar nuclei: Use of the tensor operator product basis.

Author

Kemp-Harper, R., Philp, D. J., and Kuchel, P. W.

Subjects
*FINITE nuclei, *NUCLEAR magnetic resonance
Abstract

In nuclear magnetic resonance (NMR) of I=1/2 nuclei that are scalar coupled to quadrupolar spins, a tensor operator product (TOP) basis set provides a convenient description of the time evolution of the density operator. Expressions for the evolution of equivalent I=1/2 spins, coupled to an arbitrary spin S>1/2, were obtained by explicit algebraic density operator calculations in Mathematica, and specific examples are given for S=1 and S=3/2. Tensor operators are described by the convenient quantum numbers rank and order and this imparts to the TOP basis features that enable an intuitive understanding of NMR behavior of these spin systems. It is shown that evolution as a result of J coupling alone changes the rank of tensors for the coupling partner, generating higher-rank tensors, which allow efficient excitation of S-spin multiple-quantum coherences. Theoretical predictions obtained using the TOP formalism were confirmed using multiple-quantum filtered heteronuclear spin-echo experiments and were further employed to demonstrate polarization transfer directly to multiple-quantum transitions using the insensitive nucleus enhancement by polarization transfer pulse sequence. This latter experiment is the basis of two-dimensional heteronuclear correlation experiments and direct generation of multiple-quantum S-spin coherences can therefore be exploited to yield greater spectral resolution in such experiments. Simulated spectra and experimental results are presented. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2001
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6. Adaptation of a load-inject valve for a flow injection chemiluminescence system enabling dual-reagent injection enhances understanding of environmental Fenton chemistry

Author

Suzanne M. Turner, Peter S. Liss, Matthew R. Jones, and Philp D. Nightingale

Subjects
Flow injection analysis, Detection limit, chemistry.chemical_classification, Reactive oxygen species, Chemistry, Inorganic chemistry, Direct reduced iron, Biochemistry, Analytical Chemistry, law.invention, chemistry.chemical_compound, law, Reagent, Environmental Chemistry, Seawater, Hydrogen peroxide, Spectroscopy, Chemiluminescence
Abstract

Environmental Fenton chemistry has been poorly constrained within the marine environment at a multi-component level. A simple, unique, reconfiguration of a flow-injection analytical system combined with luminol chemiluminescence allows quasi-simultaneously the measurement, using a single load-inject valve and a single photon multiplier tube, of reduced iron, Fe(II), and hydrogen peroxide. The system enables rapid, every 22s, measurements with good accuracy at environmentally relevant concentrations, less than 5% relative standard deviations on both a 5 nM Fe(II) standard and a 60 nM hydrogen peroxide standard. Limits of detection were as low as 40 pM Fe(II) and 100 pM hydrogen peroxide. The system showed excellent capability by measuring from within an organic rich seawater the photochemically induced production of Fe(II) and hydrogen peroxide and their subsequent cycling and Fenton like interactions.

Published
2013
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8. 31 p MAS-NMR of Human Erythrocytes: Independence of Cell Volume from angular Velocity

Author

Kuchel, Philip William, Bubb, William A, Ramadan, S, Chapman, B E, Philp, D J, Coen, M, Gready, Jill, Harvey, Peta, McLean, Allan J, Hook, J, Kuchel, Philip William, Bubb, William A, Ramadan, S, Chapman, B E, Philp, D J, Coen, M, Gready, Jill, Harvey, Peta, McLean, Allan J, and Hook, J

Abstract

31P magic angle spinning NMR (MAS-NMR) spectra were obtained from suspensions of human red blood cells (RBCs) that contained the cell-volume-sensitive probe molecule, dimethyl methylphosphonate (DMMP). A mathematical representation of the spectral-peak shape, including the separation and width-at-half-height in the 31P NMR spectra, as a function of rotor speed, enabled us to explore the extent to which a change in cell volume would be reflected in the spectra if it occurred. We concluded that a fractional volume change in excess of 3% would have been detected by our experiments. Thus, the experiments indicated that the mean cell volume did not change by this amount even at the highest spinning rate of 7 kHz. The mean cell volume and intracellular 31P line-width were independent of the packing density of the cells and of the initial cell volume. The relationship of these conclusions to other non-NMR studies of pressure effects on cells is noted.

Published
2004

15. Conductive carbon nanotubes for semiconductor metrology

Author

Vartanian, Victor, primary, McClure, Paul, additional, Mancevski, Vladimir, additional, Kopanski, Joseph J., additional, Rack, Philp D., additional, Sitnitsky, Ilona, additional, Bresin, Matthew D., additional, LaBella, Vince, additional, and Dunn, Kathleen, additional

Published
2010
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22. Complexities in the management of arterial compromise due to thoracic outlet syndrome

Author

Geoffrey H. White and Philp D. Colman

Subjects
Adult, congenital, hereditary, and neonatal diseases and abnormalities, medicine.medical_specialty, Brachial Artery, business.industry, Compromise, media_common.quotation_subject, Embolism, General Medicine, THORACIC OUTLET OBSTRUCTION, medicine.disease, Aneurysm, Surgery, Thoracic Outlet Syndrome, surgical procedures, operative, cardiovascular system, medicine, Humans, Female, cardiovascular diseases, business, human activities, Thoracic outlet syndrome, media_common
Abstract

A patient with arterial compromise secondary to thoracic outlet obstruction is presented and discussed. The case highlights the difficulty in management when initial surgery does not adequately decompress the outlet. It also demonstrates the risk to limb viability that may ensue.

Published
1990

25. ADAPTIVE OPTICS IN CONFOCAL MICROSCOPY

Author

O'BYRNE, J.W., primary, FEKETE, P. W., additional, ARNISON, M. R., additional, ZHAO, H., additional, SERRANO, M., additional, PHILP, D., additional, SUDIARTA, W., additional, and COGSWELL, C. J., additional

Published
1999
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36. Specific Autocatalysis in Diastereoisomeric Replicators

Author

Kassianidis, E., Pearson, R. J., and Philp, D.

Abstract

Two diastereoisomeric cycloadducts are capable of accelerating their own formation through the assembly of catalytic ternary complexes. The two cycloadducts do not have any measurable catalytic effect on the rate of formation of their diastereoisomer.

Published
2005

37. The First Spirobifluorenes Containing Two Binaphthyl Moieties

Author

Russell, A. G., Spencer, N. S., Philp, D., Kariuki, B. M., and Snaith, J. S.

Abstract

The first spirobifluorenes comprising two binaphthyl moieties with silicon or germanium at the site of fusion have been synthesized and fully characterized. X-ray crystallographic analysis reveals that both molecules have highly distorted structures, resulting in a low barrier for interconversion between the two atropisomers; the barrier was calculated from the temperature dependency of the NMR spectra.

Published
2003

39. Transfer of Stereochemical Information in a Minimal Self-Replicating System

Author

Allen, V. C., Philp, D., and Spencer, N.

Abstract

The rational design, synthesis, and characterization of a minimal self-replicating system based on a 1,3-dipolar cycloaddition between a nitrone and a maleimide is presented. The importance of molecular recognition in this system is demonstrated using a competitive inhibitor. Doping experiments demonstrate that only one of the two diastereoisomeric products of the cycloaddition reaction is capable of acting as an efficient template for its own formation, accelerating the reaction between the nitrone and maleimide and controlling the stereochemical outcome of the reaction.

Published
2001

40. Exploiting the Curtin−Hammett Principle&sbd;Recognition-Mediated Acceleration of an Aldol Reaction

Author

Howell, S. J., Ashton, P. R., Spencer, N., and Philp, D.

Abstract

Curtin−Hammett−Winstein−Holness kinetics are exploited in the acceleration of the aldol reaction between formylbenzo-15-crown-5 and acetylbenzo-15-crown-5. Potassium cations facilitate this acceleration through the fast, reversible formation of a 1:1:1 sandwich complex between the crown ethers and the metal cation.

Published
2001

41. Using Polarization Effects to Alter Chemical Reactivity:  A Simple Host Which Enhances Amine Nucleophilicity

Author

Ashton, R. P., Calcagno, P., Spencer, N., Harris, K. D. M., and Philp, D.

Abstract

The rational design of a bis(phosphine oxide) host which is capable of binding a benzylic amine is presented. The ability of this host to increase the rate of addition of 4-fluorobenzylamine to N-phenylmaleimide is rationalized in terms of the enhancement of the nucleophilicity of the benzylic amine.

Published
2000

42. Recognition-Mediated Facilitation of a Disfavored Diels−Alder Reaction

Author

Bennes, R., Philp, D., Spencer, N., Kariuki, B. M., and Harris, K. D. M.

Abstract

The rational design of a system which is capable of accelerating and facilitating a thermodynamically disfavored Diels−Alder cycloaddition between a furan and a maleimide is presented. The origins of the acceleration and facilitation of the cycloaddition reaction are traced by kinetic studies&sbd;allied to results from 1H NMR spectroscopy and X-ray crystallography&sbd;to the formation of strong intramolecular hydrogen bonds in the cycloadduct.

Published
1999

44. New crystallographic shear families derived from the rutile structure, and the possibility of continuous ordered solid solution

Author

Bursill, L. A., Hyde, B. G., and Philp, D. K.

Abstract

A number of new families of titanium and mixed titanium plus chromium oxides has been discovered, their structures all being derived from the rutile type by crystallographic shear. Different families have different CS planes (hkl), and the members of a family are distinguished by the spacing of these planes. All the structures may be described as ordered intergrowths of (121) CS and (011) APB structures, with uniform mixing. The very small intervals between the compositions of the many phases suggest that virtually continuous but ordered solid solutions are possible.

Published
1971
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46. Molecular meccano. 1. [2]rotaxanes and a [2]catenane made to order

Author

Anelli, P. L., Ashton, P. R., Ballardini, R., Balzani, V., Delgado, M., Gandoffi, M. T., Goodnow, T. T., Kaifer, A. E., Philp, D., Pietraszkiewicz, M., Luca Prodi, Reddington, M. V., Slawin, A. M. Z., Spencer, N., Fraser Stoddart, J., Vicent, C., and Williams, D. J.

50. Tracking type specific prevalence of human Papillomavirus in cervical pre-cancer: a novel sampling strategy

Author

Waters Edward K, Kaldor John, Hamilton Andrew J, Smith Anthony MA, Philp David J, Donovan Basil, and Regan David G

Subjects
Medicine (General), R5-920
Abstract

Abstract Background Surveillance designed to detect changes in the type-specific distribution of HPV in cervical intraepithelial neoplasia grade 3 (CIN-3) is necessary to evaluate the effectiveness of the Australian vaccination programme on cancer causing HPV types. This paper develops a protocol that eliminates the need to calculate required sample size; sample size is difficult to calculate in advance because HPV’s true type-specific prevalence is imperfectly known. Method A truncated sequential sampling plan that collects a variable sample size was designed to detect changes in the type-specific distribution of HPV in CIN-3. Computer simulation to evaluate the accuracy of the plan at classifying the prevalence of an HPV type as low (< 5%), moderate (5-15%), or high (> 15%) and the average sample size collected was conducted and used to assess its appropriateness as a surveillance tool. Results The plan classified the proportion of CIN-3 lesions positive for an HPV type very accurately, with >90% of simulations correctly classifying a simulated data-set with known prevalence. Misclassifying an HPV type of high prevalence as being of low prevalence, arguably the most serious kind of potential error, occurred Conclusions Truncated sequential sampling enables the proportion of CIN-3 due to an HPV type to be accurately classified using small sample sizes. Truncated sequential sampling should be used for type-specific HPV surveillance in the vaccination era.

Published
2012
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