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Full-Text Articles in Physical Sciences and Mathematics

Fabrication Of Hierarchically One-Dimensional Znxcd1-Xs/Nitio3 Nanostructures And Their Enhanced Photocatalytic Water Splitting Activity, Ling Wang, Guorui Yang, Silan Wang, Jianan Wang, Muhammad Salman Nasir, Caiyun Wang, Shengjie Peng, Wei Yan, Seeram Ramakrishna Jan 2019

Fabrication Of Hierarchically One-Dimensional Znxcd1-Xs/Nitio3 Nanostructures And Their Enhanced Photocatalytic Water Splitting Activity, Ling Wang, Guorui Yang, Silan Wang, Jianan Wang, Muhammad Salman Nasir, Caiyun Wang, Shengjie Peng, Wei Yan, Seeram Ramakrishna

Australian Institute for Innovative Materials - Papers

Hierarchically one-dimensional nanomaterials represent a kind of promising catalyst for photocatalytic of hydrogen generation, where the photoinduced charge carriers can effectively separate and be engaged in the target reaction. Herein, we report the synthesis of hierarchically one-dimensional ZnxCd1-xS/NiTiO3 nanofibers and the investigations of their photocatalytic performance. These well-designed nanofibers demonstrate a typically one-dimensional heterostructure with an excellent continuity, and the element mapping, X-ray diffraction, and X-ray photoelectron spectroscopy collectively confirm the ZnxCd1-xS nanoparticles being decorated on the surface of NiTiO3 nanofibers successfully. The ZnxCd1-xS/NiTiO3 nanofibers exhibit enhanced efficiency in photocatalytic hydrogen production under visible light, compared with the ZnxCd1-xS/TiO2 nanofibers. …


Hollow Carbon Nanobubbles: Monocrystalline Mof Nanobubbles And Their Pyrolysis, Wei Zhang, Xiangfen Jiang, Yanyi Zhao, Arnau Carne-Sanchez, Victor Malgras, Jeonghun Kim, Jung Ho Kim, Shaobin Wang, Jian Liu, Ji-Sen Jiang, Yusuke Yamauchi, Ming Hu Jan 2017

Hollow Carbon Nanobubbles: Monocrystalline Mof Nanobubbles And Their Pyrolysis, Wei Zhang, Xiangfen Jiang, Yanyi Zhao, Arnau Carne-Sanchez, Victor Malgras, Jeonghun Kim, Jung Ho Kim, Shaobin Wang, Jian Liu, Ji-Sen Jiang, Yusuke Yamauchi, Ming Hu

Australian Institute for Innovative Materials - Papers

While bulk-sized metal-organic frameworks (MOFs) face limits to their utilization in various research fields such as energy storage applications, nanoarchitectonics is believed to be a possible solution. It is highly challenging to realize MOF nanobubbles with monocrystalline frameworks. By a spatially controlled etching approach, here, we can achieve the synthesis of zeolitic imidazolate framework (ZIF-8) nanobubbles with a uniform size of less than 100 nm. Interestingly, the ZIF-8 nanobubbles possess a monocrystalline nanoshell with a thickness of around 10 nm. Under optimal pyrolytic conditions, the ZIF-8 nanobubbles can be converted into hollow carbon nanobubbles while keeping their original shapes. The …


Structure-Property Relationships Of Organic Electrolytes And Their Effects On Li/S Battery Performance, Mohammad Kaiser, Shulei Chou, Hua-Kun Liu, Shi Xue Dou, Chunsheng Wang, Jiazhao Wang Jan 2017

Structure-Property Relationships Of Organic Electrolytes And Their Effects On Li/S Battery Performance, Mohammad Kaiser, Shulei Chou, Hua-Kun Liu, Shi Xue Dou, Chunsheng Wang, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Electrolytes, which are a key component in electrochemical devices, transport ions between the sulfur/carbon composite cathode and the lithium anode in lithium-sulfur batteries (LSBs). The performance of a LSB mostly depends on the electrolyte due to the dissolution of polysulfides into the electrolyte, along with the formation of a solid-electrolyte interphase. The selection of the electrolyte and its functionality during charging and discharging is intricate and involves multiple reactions and processes. The selection of the proper electrolyte, including solvents and salts, for LSBs strongly depends on its physical and chemical properties, which is heavily controlled by its molecular structure. In …


Improvement Of Thermoelectric Properties And Their Correlations With Electron Effective Mass In Cu1.98sxse1−X, Lanling Zhao, Frank Yun Fei, Jun Wang, Funing Wang, Chunlei Wang, Jichao Li, Ji-Yang Wang, Zhenxiang Cheng, Shi Xue Dou, Xiaolin Wang Jan 2017

Improvement Of Thermoelectric Properties And Their Correlations With Electron Effective Mass In Cu1.98sxse1−X, Lanling Zhao, Frank Yun Fei, Jun Wang, Funing Wang, Chunlei Wang, Jichao Li, Ji-Yang Wang, Zhenxiang Cheng, Shi Xue Dou, Xiaolin Wang

Australian Institute for Innovative Materials - Papers

Sulphur doping effects on the crystal structures, thermoelectric properties, density-of-states, and effective mass in Cu1.98SxSe1−x were studied based on the electrical and thermal transport property measurements, and first-principles calculations. The X-ray diffraction patterns and Rietveld refinements indicate that room temperature Cu1.98SxSe1−x (x=0, 0.02, 0.08, 0.16) and Cu1.98SxSe1−x (x=0.8, 0.9, 1.0) have the same crystal structure as monoclinic-Cu2Se and orthorhombic-Cu2S, respectively. Sulphur doping can greatly enhance zT values when x is in the range of 0.8≤x≤1.0. Furthermore, all doped samples show stable thermoelectric compatibility factors over a broad temperature range from 700 to 1000K, which could greatly benefit their practical applications. …


Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner Jan 2016

Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner

Australian Institute for Innovative Materials - Papers

Synthesis, spectral and electrochemical properties of a series of new panchromatic BODIPY donor-acceptor-donor derivatives, comprising carbazole conjugated with systematically elongated framework by thiophene-based linkers were investigated. It has been found that elongation of the π-system with one thiophene unit shifts the spectra toward near infrared, while incorporation of next thiophene derivatives has only limited influence on the lowest energy transition, causing no further shift of absorption maxima. Elongation of π-conjugation of the donor arm tunes the electron properties, influencing the ionization potential (IP) and electron affinity (EA) values of the molecules. The experimental results are supported by quantum chemical computations …


The Codes Of Matter And Their Applications, Xiaolin Wang Jan 2015

The Codes Of Matter And Their Applications, Xiaolin Wang

Australian Institute for Innovative Materials - Papers

The elements in the periodic table are the building blocks used to form substances with different compositions. Nevertheless, it is the properties of substances that are decisive for their existence and practical applications. Searching for new class of materials with exotic properties has always been challenging because of the complexity of both the theoretical and the experimental approaches developed so far. Here, we propose that the three ubiquitous and paramount attributes of all existing matter charge (Q), spin (S) or rotational motion, and linear motion (K) can be used to account for the formation of different types of matter/materials and …


Towards Understanding The Lithium Transport Mechanism In Garnet-Type Solid Electrolytes: Li+ Ions Exchanges And Their Mobility At Octahedral/Tetrahedral Sites, Da-Wei Wang, Guiming Zhong, Wei Kong Pang, Zaiping Guo, Yixiao Li, Matthew J. Mcdonald, Riqiang Fu, Jin-Xiao Mi, Yong Yang Jan 2015

Towards Understanding The Lithium Transport Mechanism In Garnet-Type Solid Electrolytes: Li+ Ions Exchanges And Their Mobility At Octahedral/Tetrahedral Sites, Da-Wei Wang, Guiming Zhong, Wei Kong Pang, Zaiping Guo, Yixiao Li, Matthew J. Mcdonald, Riqiang Fu, Jin-Xiao Mi, Yong Yang

Australian Institute for Innovative Materials - Papers

The cubic garnet-type solid electrolyte Li7La3Zr2O12 with aliovalent doping exhibits a high ionic conductivity, reaching up to ∼10−3 S/cm at room temperature. Fully understanding the Li+ transport mechanism including Li+ mobility at different sites is a key topic in this field, and Li7−2x−3yAlyLa3Zr2−xWxO12 (0 ≤ x ≤ 1) are selected as target electrolytes. X-ray and neutron diffraction as well as ac impedance results show that a low amount of aliovalent substitution of Zr with W does not obviously affect the crystal structure and the activation energy of Li+ ion jumping, but it does noticeably vary the distribution of Li+ ions, …


The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou Jan 2014

The Formation Of Nano-Layered Grains And Their Enhanced Superconducting Transition Temperature In Mg-Doped Fese0.9 Bulks, Feng Lan, Zongqing Ma, Yongchang Liu, Ning Chen, Qi Cai, Huijun Li, Shaon Barua, Dipakkumar Patel, Md Shahriar Hossain, Jung Ho Kim, S X. Dou

Australian Institute for Innovative Materials - Papers

To search a proper dopant to further improve superconductivity in 11 type Fe-based superconductors makes sense to both their superconductivity mechanism and possible technological applications. In present work, Mg doped FeSe polycrystalline bulks were obtained by a two-step solid-state reaction method. Even though there are many MgSe and iron impurities existing in the Mg heavy doped FeSe bulks, they exhibit obviously increased Tc compared to undoped FeSe sample. It was found that Mg addition has little effect on the crystal lattice parameters of superconducting beta-FeSe, whereas leads to the formation of nano-layered grain structure consisted of MgSe and beta-FeSe …


Microstructural And Crystallographic Imperfections Of Mgb2 Superconducting Wire And Their Correlation With The Critical Current Density, Mohammed Shahabuddin, Nasser S. Alzayed, Sangjun Oh, Seyong Choi, Minoru Maeda, Satoshi Hata, Yusuke Shimada, Md Shahriar Al Hossain, Jung Ho Kim Jan 2014

Microstructural And Crystallographic Imperfections Of Mgb2 Superconducting Wire And Their Correlation With The Critical Current Density, Mohammed Shahabuddin, Nasser S. Alzayed, Sangjun Oh, Seyong Choi, Minoru Maeda, Satoshi Hata, Yusuke Shimada, Md Shahriar Al Hossain, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

A comprehensive study of the effects of structural imperfections in MgB2 superconducting wire has been conducted. As the sintering temperature becomes lower, the structural imperfections of the MgB2 material are increased, as reflected by detailed X-ray refinement and the normal state resistivity. The crystalline imperfections, caused by lattice disorder, directly affect the impurity scattering between the π and σ bands of MgB2, resulting in a larger upper critical field. In addition, low sintering temperature keeps the grain size small, which leads to a strong enhancement of pinning, and thereby, enhanced critical current density. Owing to both the impurity scattering and …


Thermoelectric Properties Of Ca3co4o9 And Ca2.8bi0.2co4o9 Thin Films In Their Island Formation Mode, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou Jan 2013

Thermoelectric Properties Of Ca3co4o9 And Ca2.8bi0.2co4o9 Thin Films In Their Island Formation Mode, Priyanka Jood, Germanas Peleckis, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Ca3Co4O9 and Ca2.8Bi 0.2Co4O9 thin films were fabricated on LaAlO3 (LAO) substrate using pulsed laser deposition technique and were studied for their thermoelectric (TE) properties in Stranski-Krastanov mode for the first time. The thin films consisted of 3D clusters/islands on a 14-nm thick 2D layer with cluster density being higher for Ca 2.8Bi0.2Co4O9 thin films. The clusters also represent areas of dislocation and therefore act as carrier scattering centers, which leads to a temperature-activated type conductivity. Seebeck coefficient as high as 136 and 163 u V/K was measured for the Ca 3Co4O9 and Ca2.8Bi 0.2Co4O9 thin films, respectively, which is …


A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou Jan 2013

A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Transition metal oxide (Mn3O4, Fe2O3, Co3O4, and ZnO) and reduced graphene oxide (RGO) composites were successfully synthesized via a hydrothermal method using the direct reaction between the corresponding metal powder and graphene oxide (GO). In this process, the GO can be reduced by transition metal powder in water, and the nanosized metal oxide can be obtained, and homogeneously mixed with and wrapped by RGO to form a metal oxide/RGO composite at the same time. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy were used to characterize the as-prepared materials. The different experimental parameters, including reactants, …


Fabrication Of Graphene Electrodes By Electrophoretic Deposition And Their Synergistic Effects With Pedot And Platinum, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Gordon G. Wallace Jan 2013

Fabrication Of Graphene Electrodes By Electrophoretic Deposition And Their Synergistic Effects With Pedot And Platinum, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

This research presents a useful electrophoretic deposition (EPD) technique for electrode fabrication from an aqueous colloidal solution of graphene to produce graphene electrodes by the deposition of graphene on to indium-tin oxide (ITO) coated glass. Resultant graphene electrodes are composited with conducting polymer (PEDOT), and platinum nanoparticles, to investigate their synergistic effects. Firstly, PEDOT is composited with graphene by electropolymerization on to the graphene layer. The graphene/PEDOT electrodes demonstrate an improvement in electrochemical response in tetrabutylammonium perchlorate/ acetonitrile solution. Secondly, graphene electrodes are composited with platinum by EPD of platinum nanoparticles on to the graphene layer. The resultant graphene/platinum electrodes …


New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan Jan 2012

New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan

Faculty of Informatics - Papers (Archive)

Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i. e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption …


Solitary Waves And Their Stability In Colloidal Media: Semi-Analytical Solutions, Timothy R. Marchant, N F. Smyth Jan 2012

Solitary Waves And Their Stability In Colloidal Media: Semi-Analytical Solutions, Timothy R. Marchant, N F. Smyth

Faculty of Informatics - Papers (Archive)

Spatial solitary waves in colloidal suspensions of spherical dielectric nanopartides are considered. The interaction of the nanoparticles is modelled as a hard-sphere gas, with the Carnahan-Starling formula used for the gas compressibility. Semi-analytical solutions, for both one and two spatial dimensions, arc derived using an averaged Lagrangian and suitable trial functions for the solitary waves. Power versus propagation constant curves and neutral stability curves are obtained for both cases, which illustrate that multiple solution branches occur for both the one and two dimensional geometries. For the one-dimensional case it is found that three solution branches (with a bistable regime) occur. …


A Unified Study Of Epidemic Routing Protocols And Their Enhancements, Zuyong Feng, Kwan-Wu Chin Jan 2012

A Unified Study Of Epidemic Routing Protocols And Their Enhancements, Zuyong Feng, Kwan-Wu Chin

Faculty of Informatics - Papers (Archive)

Epidemic protocols belong to a class of routing paradigm that have wide ranging applications in Delay Tolerant Networks (DTNs) due to their simplicity, low delays, and little to no reliance on special nodes. To this end, a comprehensive study of their performance will serve as an important guide to future protocol designers. Unfortunately, to date, there is no work that studies epidemic routing protocols using a common framework that evaluates their performance objectively using the same mobility model and parameters. To this end, we study four categories of epidemic routing protocols. Namely, P-Q epidemic, epidemic with Time-To-Live (TTL), epidemic with …


Lime Muds And Their Genesis Off-Northwestern India During The Late Quaternary, V P. Rao, A Anil Kumar, S W A Naqvi, Allan R. Chivas, B Sekar, Pratima M. Kessarkar Jan 2012

Lime Muds And Their Genesis Off-Northwestern India During The Late Quaternary, V P. Rao, A Anil Kumar, S W A Naqvi, Allan R. Chivas, B Sekar, Pratima M. Kessarkar

Faculty of Science - Papers (Archive)

Two sediment types were found in five gravity cores collected from water depths between 56 m and 121 m along the northwestern continental margin of India: lime muds were abundant in the lower section while siliciclastic sediments dominated the upper section. Lime mud-dominated sediments in shelf cores contained 60%–75% carbonate, 0.3%–0.6% Sr and terrigenous minerals, whereas those at the shelf break were found to have >90% carbonate, 0.6%–0.8% Sr and traces of terrigenous minerals. Aragonite needles showing blunt edges, jointed needles and needles wrapped in smooth aragonite cement were found to be common. Stable (O and C) isotopes of lime …


Selective Reduction Of Hydroperoxyeicosatetraenoic Acids To Their Hydroxy Derivatives By Apolipoprotein D: Implications For Lipid Antioxidant Activity And Alzheimer's Disease, Surabhi Bhatia, Bianca Knoch, Jenny Wong, Woojin Scott Kim, Paul Else, Aaron J. Oakley, Brett Garner Jan 2012

Selective Reduction Of Hydroperoxyeicosatetraenoic Acids To Their Hydroxy Derivatives By Apolipoprotein D: Implications For Lipid Antioxidant Activity And Alzheimer's Disease, Surabhi Bhatia, Bianca Knoch, Jenny Wong, Woojin Scott Kim, Paul Else, Aaron J. Oakley, Brett Garner

Faculty of Science - Papers (Archive)

ApoD (apolipoprotein D) is up-regulated in AD (Alzheimer's disease) and upon oxidative stress. ApoD inhibits brain lipid peroxidation in vivo, but the mechanism is unknown. Specific methionine residues may inhibit lipid peroxidation by reducing radical-propagating L-OOHs (lipid hydroperoxides) to non-reactive hydroxides via a reaction that generates MetSO (methionine sulfoxide). Since apoD has three conserved methionine residues (Met49, Met93 and Met157), we generated recombinant proteins with either one or all methionine residues replaced by alanine and assessed their capacity to reduce HpETEs (hydroperoxyeicosatetraenoic acids) to their HETE (hydroxyeicosatetraenoic acid) derivatives. ApoD, apoDM49-A and apoDM157-A all catalysed the reduction of HpETEs to …


Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer Jan 2012

Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer

Australian Institute for Innovative Materials - Papers

Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900 degress C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/ PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst …


The Synthesis Of Lamellar Nano Mgb2 Grains With Nanoimpurities, Flux Pinning Centers And Their Significantly Improved Critical Current Density, Zongqing Ma, Yongchang Liu, Qi Cai Jan 2012

The Synthesis Of Lamellar Nano Mgb2 Grains With Nanoimpurities, Flux Pinning Centers And Their Significantly Improved Critical Current Density, Zongqing Ma, Yongchang Liu, Qi Cai

Australian Institute for Innovative Materials - Papers

MgB2 superconductors with unique microstructures were rapidly fabricated at low temperatures, and exhibited significantly improved critical current density (Jc). According to the microstructure observations, the prepared samples consisted of lamellar nano MgB2 grains with many embedded nanoimpurities (about 10 nm). The formation of these lamellar nano MgB2 grains is associated with the presence of a local Mg-Cu liquid at sintering temperatures as low as 575°C. The ball milling treatment of the original powders also plays a positive role in the growth of lamellar grains. Based on an analysis of the relationship between resistivity and temperature, the lamellar nano MgB2 grains …


Negotiating Change: Working With Children And Their Employers To Transform Child Domestic Work In Iringa, Tanzania, Natascha Klocker Jan 2011

Negotiating Change: Working With Children And Their Employers To Transform Child Domestic Work In Iringa, Tanzania, Natascha Klocker

Faculty of Science - Papers (Archive)

This paper documents the practical and action-oriented findings of an investigation into child domestic work undertaken in Iringa, Tanzania from 2005 to 2007. It provides an overview of the experiences of both child domestic workers and their employers, before discussing their suggestions for how child domestic working arrangements may be improved. The latter sections of the paper relate the attempts to regulate child domestic work that emerged from such dialogue. In providing detailed information on that process, the paper is positioned within the field of action research and resists the boundary frequently applied between academia and activism. It also moves …


Corrigendum To ‘‘The Chaperone Action Of Bovine Milk As1- And As2-Caseins And Their Associated Form As-Casein’’ [Arch. Biochem. Biophys. 510 (2011) 42–52], Teresa M. Treweek, David C. Thorn, William E. Price, John A. Carver Jan 2011

Corrigendum To ‘‘The Chaperone Action Of Bovine Milk As1- And As2-Caseins And Their Associated Form As-Casein’’ [Arch. Biochem. Biophys. 510 (2011) 42–52], Teresa M. Treweek, David C. Thorn, William E. Price, John A. Carver

Faculty of Science - Papers (Archive)

No abstract provided.


What Students Are Telling Us About Why They Left Their Ict Course, Madeleine R. H Roberts, Tanya Mcgill, Tony Koppi Jan 2011

What Students Are Telling Us About Why They Left Their Ict Course, Madeleine R. H Roberts, Tanya Mcgill, Tony Koppi

Faculty of Informatics - Papers (Archive)

Student attrition is an issue of particular concern in the field of ICT because the industry faces staffing shortfalls. The study described in this paper provides further understanding of the causes of attrition from ICT courses by exploring the reasons students give for leaving their ICT courses. An online survey of early leavers from four Australian universities was conducted. The results show that many factors can contribute to the attrition of ICT students, and that for many students it is a combination of issues that leads to their withdrawal. Only a relatively small number of ex-students had experienced serious life …


Nanoesi Mass Spectrometry Of Rubisco And Rubisco Activase Structures And Their Interactions With Nucleotides And Sugar Phosphates, Michelle Blayney, Spencer M. Whitney, Jennifer L. Beck Jan 2011

Nanoesi Mass Spectrometry Of Rubisco And Rubisco Activase Structures And Their Interactions With Nucleotides And Sugar Phosphates, Michelle Blayney, Spencer M. Whitney, Jennifer L. Beck

Faculty of Science - Papers (Archive)

Ribulose bisphosphate carboxylase/oxygenase (Rubisco) is the protein that is responsible for the fixation of carbon dioxide in photosynthesis. Inhibitory sugar phosphate molecules, which can include its substrate ribulose-1,5- bisphosphate (RuBP), can bind to Rubisco catalytic sites and inhibit catalysis. These are removed by interaction with Rubisco activase (RA) via an ATP hydrolytic reaction. Here we show the first nanoESI mass spectra of the hexadecameric Rubisco and of RA from a higher plant (tobacco). The spectra of recombinant, purified RA revealed polydispersity in its oligomeric forms (up to hexamer) and that ADP was bound. ADP was removed by dialysis against a …


The Interaction Of Alphab-Crystallin With Mature Alpha-Synuclein Amyloid Fibrils Inhibits Their Elongation, Christopher A. Waudby, Tuomas P. J Knowles, Glyn L. Devlin, Jeremy N. Skepper, Heath Ecroyd, John A. Carver, Mark E. Welland, John Christodoulou, Christopher M. Dobson, Sarah Meehan Jan 2010

The Interaction Of Alphab-Crystallin With Mature Alpha-Synuclein Amyloid Fibrils Inhibits Their Elongation, Christopher A. Waudby, Tuomas P. J Knowles, Glyn L. Devlin, Jeremy N. Skepper, Heath Ecroyd, John A. Carver, Mark E. Welland, John Christodoulou, Christopher M. Dobson, Sarah Meehan

Faculty of Science - Papers (Archive)

alphaB-Crystallin is a small heat-shock protein (sHsp) that is colocalized with alpha-synuclein (alphaSyn) in Lewy bodies—the pathological hallmarks of Parkinson's disease—and is an inhibitor of alphaSyn amyloid fibril formation in an ATP-independent manner in vitro. We have investigated the mechanism underlying the inhibitory action of sHsps, and here we establish, by means of a variety of biophysical techniques including immunogold labeling and nuclear magnetic resonance spectroscopy, that alphaB-crystallin interacts with alphaSyn, binding along the length of mature amyloid fibrils. By measurement of seeded fibril elongation kinetics, both in solution and on a surface using a quartz crystal microbalance, this binding …


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 Jan 2010

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 …


Patterns Of Demography For Rocky-Shore, Intertidal Invertebrates Approaching Their Geographical Range Limits: Tests Of The Abundant-Centre Hypothesis In South-Eastern Australia, Eszter Z. Hidas, David J. Ayre, Todd E. Minchinton Jan 2010

Patterns Of Demography For Rocky-Shore, Intertidal Invertebrates Approaching Their Geographical Range Limits: Tests Of The Abundant-Centre Hypothesis In South-Eastern Australia, Eszter Z. Hidas, David J. Ayre, Todd E. Minchinton

Faculty of Science - Papers (Archive)

The abundant-centre hypothesis predicts that species' abundances peak at the centre of their geographical ranges and decline gradually towards their range limits. We tested predictions of this hypothesis for three rocky-shore, intertidal invertebrates with planktonic larvae (the whelk, Morula marginalba, the snail, Afrolittorina pyramidalis, and the barnacle, Tesseropora rosea) by quantifying their patterns of abundance and size, and inferring pulses of recruitment from size-frequency distributions, at multiple spatial scales spanning a 600-km region in south-eastern Australia and encompassing roughly the southern third of their geographical ranges. At the regional scale, abundances for all species were, as predicted, dramatically lower at …


Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu Jan 2009

Dynamic Universal Accumulators For Ddh Groups And Their Application To Attribute-Based Anonymous Credential Systems, Man Ho Au, Patrick P. Tsang, Willy Susilo, Yi Mu

Faculty of Informatics - Papers (Archive)

We present the first dynamic universal accumulator that allows (1) the accumulation of elements in a DDH-hard group G and (2) one who knows x such that y = gx has - or has not - been accumulated, where g generates G, to efficiently prove her knowledge of such x in zero knowledge, and hence without revealing, e.g., x or y. We introduce the Attribute-Based Anonymous Credential System, which allows the verifier to authenticate anonymous users according to any access control policy expressible as a formula of possibly negated boolean user attributes. We construct the system from our accumulator.


Sulphur-Tagged Metal-Organic Frameworks And Their Post-Synthetic Oxidation, Andrew D. Burrows, Christopher G. Frost, Mary F. Mahon, Christopher Richardson Jan 2009

Sulphur-Tagged Metal-Organic Frameworks And Their Post-Synthetic Oxidation, Andrew D. Burrows, Christopher G. Frost, Mary F. Mahon, Christopher Richardson

Faculty of Science - Papers (Archive)

No abstract provided.


Molecular And Morphological Description Of A Hepatozoon Species In Reptiles And Their Ticks In The Northern Territory, Australia, Inger-Marie E. Vilcins, Beata Ujvari, Julie M. Old, Elizabeth Deane Jan 2009

Molecular And Morphological Description Of A Hepatozoon Species In Reptiles And Their Ticks In The Northern Territory, Australia, Inger-Marie E. Vilcins, Beata Ujvari, Julie M. Old, Elizabeth Deane

Faculty of Science - Papers (Archive)

Ticks, representing 3 species of Amblyomma, were collected from the water python (Liasis fuscus) and 3 additional reptile species in the Northern Territory, Australia, and tested for the presence of Hepatozoon sp., the most common blood parasites of snakes. In addition, blood smears were collected from 5 reptiles, including the water python, and examined for the presence of the parasite. Hepatozoon sp. DNA was detected in all tick and reptile species, with 57.7% of tick samples (n = 187) and 35.6% of blood smears (n = 35) showing evidence of infection. Phylogenetic analysis of the 18S rRNA gene demonstrated that …


Nanofiber Mats From Dna, Swnts, And Poly(Ethylene Oxide) And Their Application In Glucose Biosensors, Jun Chen, Chee O. Too, Gordon G. Wallace, Tuan A Nguyen, Violetta Misoska, Yong Liu Jan 2008

Nanofiber Mats From Dna, Swnts, And Poly(Ethylene Oxide) And Their Application In Glucose Biosensors, Jun Chen, Chee O. Too, Gordon G. Wallace, Tuan A Nguyen, Violetta Misoska, Yong Liu

Faculty of Science - Papers (Archive)

Ultrafine fibers with diameters ranging from 50 to 300 nm were prepared from DNA/single-walled carbon nanotubes (SWNTs)/poly(ethylene oxide) blended dispersion. Well-defined electrospun fibers were obtained by good control of key dispersion properties related to electrospinning, such as ionic conductivity, surface tension, and viscosity. Raman spectroscopy confirmed the presence of SWNT in the resulting fibers, indicating good interaction between DNA and SWNT. The resulting fibers also exhibited electroactive behavior and could be used as an immobilization matrix for a glucose oxidase enzyme biosensor. The sensor response was linear up to 20 mM glucose with a sensitivity of 2.4 mA cm -2 …