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Full-Text Articles in Physical Sciences and Mathematics
Synthesis Of Hyacinthacine B-3 And Purported Hyacinthacine B-7, Christopher W.G. Au, Robert J. Nash, Stephen G. Pyne
Synthesis Of Hyacinthacine B-3 And Purported Hyacinthacine B-7, Christopher W.G. Au, Robert J. Nash, Stephen G. Pyne
Faculty of Science - Papers (Archive)
The synthesis of hyacinthacines B-3 and B-7 has confirmed the structure of the former alkaloid and shown that the structure of the latter is incorrect.
Total Synthesis Of Uniflorine A, Casuarine, Australine, 3-Epi-Australine, And 3,7-Di-Epi-Australine From A Common Precursor, Thunwadee Ritthiwigrom, Anthony C. Willis, Stephen G. Pyne
Total Synthesis Of Uniflorine A, Casuarine, Australine, 3-Epi-Australine, And 3,7-Di-Epi-Australine From A Common Precursor, Thunwadee Ritthiwigrom, Anthony C. Willis, Stephen G. Pyne
Faculty of Science - Papers (Archive)
A flexible method for the diastereoselective total synthesis of the pyrrolizidine alkaloids Uniflorine A, casuarine, australine, and 3-epi-australine and the unnatural epimer 3,7-di-epi-australine from a common chiral 2,5-dihydropyrrole precursor is described.
Distribution Of Class 1 Integrons With Is26-Mediated Deletions In Their 3'-Conserved Segments In Escherichia Coli Of Human And Animal Origin., Fay E. Dawes, Alexander Kuzevski, Karl A Bettelheim, Michael A Hornitzky, Steven P Djordjevic, Mark J. Walker
Distribution Of Class 1 Integrons With Is26-Mediated Deletions In Their 3'-Conserved Segments In Escherichia Coli Of Human And Animal Origin., Fay E. Dawes, Alexander Kuzevski, Karl A Bettelheim, Michael A Hornitzky, Steven P Djordjevic, Mark J. Walker
Faculty of Science - Papers (Archive)
Class 1 integrons play a role in the emergence of multi-resistant bacteria by facilitating the recruitment of gene cassettes encoding antibiotic resistance genes. 512 E. coli strains sourced from humans (n = 202), animals (n = 304) and the environment (n = 6) were screened for the presence of the intI1 gene. In 31/79 integron positive E. coli strains, the gene cassette regions could not be PCR amplified using standard primers. DNA sequence analysis of 6 serologically diverse strains revealed atypical integrons harboured the dfrA5 cassette gene and only 24 bp of the integron 3'-conserved segment (CS) remained, due to …
Ontology Matching Techniques: A 3-Tier Classification Framework, Nelson K. Y. Leung, Seung Hwan Kang, Sim Kim Lau, Joshua Fan
Ontology Matching Techniques: A 3-Tier Classification Framework, Nelson K. Y. Leung, Seung Hwan Kang, Sim Kim Lau, Joshua Fan
Faculty of Informatics - Papers (Archive)
No abstract provided.
Olsr-R^3: Optimised Link State Routing With Reactive Route Recovery, Jerry Chun-Ping Wang, Farzad Safaei, Mehran Abolhasan, Daniel R. Franklin
Olsr-R^3: Optimised Link State Routing With Reactive Route Recovery, Jerry Chun-Ping Wang, Farzad Safaei, Mehran Abolhasan, Daniel R. Franklin
Faculty of Informatics - Papers (Archive)
The Optimised Link State Routing (OLSR) is a proactive routing protocol which relies on periodical broadcast of routing packets. However, due to the one-to-many relationship of broadcast traffic, the delivery of these packets can not be guaranteed by underlying MAC protocol, particularly in a congested condition. In this paper, the possible routing pathologies and failures of OLSR in a congested network are explored. In addition, a hybrid routing protocol which integrates OLSR with Reactive Route Recovery (OLSR-R3) is proposed to rectify the erratic routing behaviour described in this paper. Simulation studies are presented which show that the proposed solution is …
Fragmentation Pathways Of 2,3-Dimethyl-2,3-Dinitrobutane Cations In The Gas Phase, Martin Paine, Benjamin Kirk, Simon Ellis-Steinborner, Stephen J. Blanksby
Fragmentation Pathways Of 2,3-Dimethyl-2,3-Dinitrobutane Cations In The Gas Phase, Martin Paine, Benjamin Kirk, Simon Ellis-Steinborner, Stephen J. Blanksby
Faculty of Science - Papers (Archive)
2,3-Dimethyl-2,3-dinitrobutane (DMNB) is an explosive taggant added to plastic explosives during manufacture making them more susceptible to vapour-phase detection systems. In this study, the formation and detection of gas-phase [M+H](+), [M+Li](+), [M+NH4](+) and [M+Na](+) adducts of DMNB was achieved using electrospray ionisation on a triple quadrupole mass spectrometer. The [M+H](+) ion abundance was found to have a strong dependence on ion source temperature, decreasing markedly at source temperatures above 50 degrees C. In contrast, the [M+Na](+) ion demonstrated increasing ion abundance at source temperatures up to 105 degrees C. The relative susceptibility of DMNB adduct ions toward dissociation was investigated …
(-)-Epigallocatechin-3-Gallate (Egcg) Maintains K-Casein In Its Pre-Fibrillar State Without Redirecting Its Aggregation Pathway, Sean A. Hudson, Heath Ecroyd, Francis C. Dehle, Ian F. Musgrave, John Carver
(-)-Epigallocatechin-3-Gallate (Egcg) Maintains K-Casein In Its Pre-Fibrillar State Without Redirecting Its Aggregation Pathway, Sean A. Hudson, Heath Ecroyd, Francis C. Dehle, Ian F. Musgrave, John Carver
Faculty of Science - Papers (Archive)
The polyphenol (-)-epigallocatechin-3-gallate (EGCG) has recently attracted much research interest in the field of protein-misfolding diseases because of its potent anti-amyloid activity against amyloid-beta, alpha-synuclein and huntingtin, the amyloid-fibril-forming proteins involved in Alzheimer's, Parkinson's and Huntington's diseases, respectively. EGCG redirects the aggregation of these polypeptides to a disordered off-folding pathway that results in the formation of non-toxic amorphous aggregates. whether this anti-fibril activity is specific to these disease-related target proteins or ismore generic remains to be established. In addition, the mechanism by which EGCG exerts its effects, as with all anti-amyloidogenic polyphenols, remains unclear. To address these aspects, we have …
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The imidazole and pyridine rings in the title compound, C9H8N4O4, are twisted with respect to one another, with a dihedral angle of 48.30 (4)°. The nitro group is almost coplanar with the imidazole plane. The crystal packing involves some weak C—H...N and C—H...O hydrogen bonds, of which the strongest, between the imidazole CH group and a nitro O atom [H...O 2.396 (15) Å], forms a centrosymmetric dimer.
Infrared Spectra Of The Li +_(H 2)N(N=1-3) Cation Complexes, C Emmeluth, B L. J Poad, C D. Thompson, G H. Weddle, E J. Bieske
Infrared Spectra Of The Li +_(H 2)N(N=1-3) Cation Complexes, C Emmeluth, B L. J Poad, C D. Thompson, G H. Weddle, E J. Bieske
Faculty of Science - Papers (Archive)
The Li+–(H2)n n = 1–3 complexes are investigated through infrared spectra recorded in the H–H stretch region (3980–4120 cm−1) and through ab initio calculations at the MP2∕aug-cc-pVQZ level. The rotationally resolved H–H stretch band of Li+–H2 is centered at 4053.4 cm−1 [a −108 cm−1 shift from the Q1(0) transition of H2]. The spectrum exhibits rotational substructure consistent with the complex possessing a T-shaped equilibrium geometry, with the Li+ ion attached to a slightly perturbed H2 molecule. Around 100 rovibrational transitions belonging to …
~3,850 Ma Tonalites In The Nuuk Region, Greenland: Geochemistry And Their Reworking Within An Eoarchaean Gneiss Complex, Allen P. Nutman, Vickie C. Bennett, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka
~3,850 Ma Tonalites In The Nuuk Region, Greenland: Geochemistry And Their Reworking Within An Eoarchaean Gneiss Complex, Allen P. Nutman, Vickie C. Bennett, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka
Faculty of Science - Papers (Archive)
The Eoarchaean (>3,600 Ma) Itsaq Gneiss Complex of southern West Greenland is dominated by polyphase orthogneisses with a complex Archaean tectonothermal history. Some of the orthogneisses have c. 3,850 Ma zircons, and they vary from rare single phase metatonalites to more common complexly banded migmatites. This is due to heterogeneous strain, in situ anatexis and granitic veining superimposed during younger tectonothermal events. In the single-phase tonalites with c. 3,850 Ma zircon, oscillatory-zoned prismatic zircon is all 3,850 Ma old, but shows patchy ancient loss of radiogenic Pb. SHRIMP spot analyses and laser ablation ICP-MS depth profiling show that thin …
Crystallization And Diffraction Data Of 1h-3-Hydroxy-4-Oxoquinoline 2,4-Dioxygenase: A Cofactor-Free Oxygenase Of The Alpha/Beta-Hydrolase Family, Ruhu Qi, Susanne Fetzner, Aaron J. Oakley
Crystallization And Diffraction Data Of 1h-3-Hydroxy-4-Oxoquinoline 2,4-Dioxygenase: A Cofactor-Free Oxygenase Of The Alpha/Beta-Hydrolase Family, Ruhu Qi, Susanne Fetzner, Aaron J. Oakley
Faculty of Science - Papers (Archive)
1H-3-Hydroxy-4-oxoquinoline 2,4-dioxygenase (QDO) from Pseudomonas putida 33/1 catalyses the oxygenolysis of 1H-3-hydroxy-4-oxoquinoline to form N-formylanthranilic acid and carbon monoxide without the aid of cofactors. Both N-terminally His6-tagged and native QDO were overexpressed in Escherichia coli and purified by conventional chromatographic procedures. Untagged QDO, but not His6-tagged QDO, was crystallized by the vapour-diffusion method, giving hexagonal bipyramid crystals belonging to space group P6(1)22. Selenomethionine-containing native QDO was prepared and crystallized under identical conditions. The unit-cell parameters were a = b = 90.1, c = 168.6 A, alpha = beta = 90, gamma = 120 degrees. Using synchrotron radiation, these crystals diffract …
1,8,14,20-Tetraoxa-11,23-Dithiatricyclo[21.3.0.09,13]Hexacosa-9,12,21,24-Tetraene, Pawel Wagner, Maciej Kubicki, Mieczyslaw Lapkowski
1,8,14,20-Tetraoxa-11,23-Dithiatricyclo[21.3.0.09,13]Hexacosa-9,12,21,24-Tetraene, Pawel Wagner, Maciej Kubicki, Mieczyslaw Lapkowski
Australian Institute for Innovative Materials - Papers
Crystals of the title compd. are orthorhombic, space group Pbca; Z = 4. Mols. lie on crystallog. centers of inversion, but have approx. C2h mol. symmetry. The parallel thiophene rings are almost exactly planar; the overall conformation of the mol. is chair-like. The mols. have voids that could, in principle, accommodate small guest mols., although in the crystal structure access to these voids is blocked by neighboring mols.
A Flip-Disorder In The Structure Of 3-[2-(Anthracen-9-Yl)Ethenyl]Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki
A Flip-Disorder In The Structure Of 3-[2-(Anthracen-9-Yl)Ethenyl]Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
In the crystal structure of the title compound, C20H14S, the thiophene rings are disordered; such a flip-type disorder is typical for simple, monosubstituted thiophene derivatives. Two planar fragments, the thiophene and the anthracene units, are almost perpendicular in order to relieve the H⋯H steric strains. The crystal packing is determined by van der Waals interactions, π–π stacking between the anthracene fragments, and some weak C—H⋯S and C—H⋯π short directional contacts.
3-Methyl-5-Nitrouracil, Maciej Kubicki, Pawel Wagner
3-Methyl-5-Nitrouracil, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The molecules of the title compound, C5H5N3O4, are approximately planar. The nitro group makes a dihedral angle of 1.3 (4)° with the plane of the six-membered ring. This coplanar disposition is a reason for the changes in valence angles in the vicinity of the nitro group. Molecules are connected into dimers by means of N—H⋯O hydrogen bonds, and these dimers make larger structures with the help of relatively short C—H⋯O hydrogen bonds.
Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer
Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer
Australian Institute for Innovative Materials - Papers
Properties and behavior of a group of four newly synthesized derivatives of terthiophene and terthienylenvinylene was studied. All four investigated monomers bear a 1,3-indandione substituent at the central thiophene ring and two of them (ThIV, ThIVM) have additional vinyl bonds introduced between the thiophene rings. In addition, ThIM and ThIVM have 5 positions of the two terminal rings blocked with methyl groups. The measurements were done using cyclic voltamperometry (CV) in solutions of 0.1M Bu4NBF4 in CH2Cl2. It was found that ThI and ThIV polymerise easily. CV of ThI reveals a reduction peak …
Microcosm: A Lost Cost 3-D Wireless Sensor Test-Bed Within A Controllable Environment, David Marsh, Richard Tynan, Stephen T. Beirne, Roderick L. Shepherd, Gregory O'Hare, Dermot Diamond, Brian Corcoran
Microcosm: A Lost Cost 3-D Wireless Sensor Test-Bed Within A Controllable Environment, David Marsh, Richard Tynan, Stephen T. Beirne, Roderick L. Shepherd, Gregory O'Hare, Dermot Diamond, Brian Corcoran
Faculty of Science - Papers (Archive)
This paper describes the creation of Microcosm, a low cost wireless sensor network test-bed within a controlled environment to facilitate WSN experiments in three dimensions, with an emphasis on executing sensing-related experiments. The design of the sensing hardware, software, support tools and the experimental environment itself are given. Issues related to the design of this configuration are discussed, with the potential pitfalls and eventual solutions alike given. Finally, current and future uses for the test-bed are listed.
Harmonic Allocation Constant For Implementation Of As/Nzs 61000.3.6, D A. Robinson, Victor J. Gosbell, Sarath Perera
Harmonic Allocation Constant For Implementation Of As/Nzs 61000.3.6, D A. Robinson, Victor J. Gosbell, Sarath Perera
Faculty of Informatics - Papers (Archive)
Allocation of equal harmonic emission rights to MV customers having the same maximum demand is a key concept in the new Australian harmonic standard AS/NZS 61000.3.6 [1]. Some difficulty can arise with the application of the standard when customers are spread out along a feeder with significantly different fault levels. One proposed method of overcoming this problem is to reduce the allocation as the square root of the fault level [2]. This method requires the calculation of an allocation constant that is applied to all customers connected to the same zone substation. This paper gives a methodology for calculating the …
The Application Of Iec 61000-3-6 To Mv Systems In Australia, Victor J. Gosbell, D A. Robinson, Sarath Perera, Alex Baitch
The Application Of Iec 61000-3-6 To Mv Systems In Australia, Victor J. Gosbell, D A. Robinson, Sarath Perera, Alex Baitch
Faculty of Informatics - Papers (Archive)
IEC 61000-3-6 [1] comprises a number of stages and tests to determine harmonic emission allowances for customers connected to MV or HV networks. Of particular importance is the section concerning loads distributed along a feeder, each having a different fault level. Although a common situation, the treatment given in the IEC standard is poorly described, being largely illustrated by one atypical example. This allows simplifying assumptions to be made which are invalid in practical cases. This paper outlines a more general approach that is relatively easy to apply.