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Full-Text Articles in Social and Behavioral Sciences

Systematic Enso-Driven Nutrient Variability Recorded By Central Equatorial Pacific Corals, Michele Lavigne, Intan S. Nurhati, Kim M. Cobb, Helen V. Mcgregor, Daniel Sinclair, Robert M. Sherrell Aug 2013

Systematic Enso-Driven Nutrient Variability Recorded By Central Equatorial Pacific Corals, Michele Lavigne, Intan S. Nurhati, Kim M. Cobb, Helen V. Mcgregor, Daniel Sinclair, Robert M. Sherrell

Faculty of Science, Medicine and Health - Papers: part A

[1] Variations in ocean productivity are driven largely by nutrient supply to the photic zone, but temporal records of nutrient variability are sparse. Here we show scleractinian coral P/Ca proxy records of variations in phosphate concentrations during El Niño Southern Oscillation (ENSO) cycles in the central equatorial Pacific. Covarying P/Ca records in Porites corals from Christmas and Fanning Islands show a regional ~40% decrease during the upwelling relaxation of the 1997–1998 El Niño, consistent with less frequent nutrient measurements from this area. Similar ~35–45% skeletal P/Ca decreases occur during the 1982–1983 and 1986–1987 ...


Rapid Cascade Synthesis Of Poly-Heterocyclic Architectures From Indigo, Alireza Shakoori Ghasabi, John Bremner, Anthony C. Willis, Rachada Haritakun, Paul A. Keller Jun 2013

Rapid Cascade Synthesis Of Poly-Heterocyclic Architectures From Indigo, Alireza Shakoori Ghasabi, John Bremner, Anthony C. Willis, Rachada Haritakun, Paul A. Keller

Faculty of Science, Medicine and Health - Papers: part A

The base-induced propargylation of the dye indigo results in the rapid and unprecedented one-pot synthesis of highly functionalized representatives of the pyrazino[1,2-a:4,3-a′]diindole, pyrido[1,2-a:3,4-b′]diindole and benzo[b]indolo[1,2-h]naphthyridine heterocyclic systems, with the last two reflecting the core skeleton of the anticancer/antiplasmodial marine natural products fascaplysin and homofascaplysins and a ring B-homologue, respectively. The polycyclic compounds 6–8, whose structures were confirmed through single-crystal X-ray crystallographic analysis, arise from sequential inter/intramolecular substitution–addition reactions, and in some cases, ring rearrangement reactions. Preliminary studies on controlling the reaction ...


Rates Of Shoreline Change Along The Coast Of Bangladesh, Md. Golam Mahabub Sarwar, Colin D. Woodroffe May 2013

Rates Of Shoreline Change Along The Coast Of Bangladesh, Md. Golam Mahabub Sarwar, Colin D. Woodroffe

Faculty of Science, Medicine and Health - Papers: part A

Bangladesh, at the confluence of the sediment-laden Ganges and Brahmaputra Rivers, supports an enormous and rapidly growing population (>140 million in 2011), across low-lying alluvial and delta plains that have accumulated over the past few thousand years. It has been identified as one of the most vulnerable places in the world to the impacts of climate change and sea-level rise. Although abundant sediment supply has resulted in accretion on some parts of the coast of Bangladesh, others are experiencing rapid erosion. We report a systematic assessment of rates of shoreline change over a 20-year period from 1989 to 2009, using ...


Concise Synthesis Of (-)-Steviamine And Analogues And Their Glycosidase Inhibitory Activities, Nadechanok Jiangseubchatveera, Marc E. Bouillon, Boonsom Liawruangrath, Saisunee Liawruangrath, Robert J. Nash, Stephen G. Pyne Apr 2013

Concise Synthesis Of (-)-Steviamine And Analogues And Their Glycosidase Inhibitory Activities, Nadechanok Jiangseubchatveera, Marc E. Bouillon, Boonsom Liawruangrath, Saisunee Liawruangrath, Robert J. Nash, Stephen G. Pyne

Faculty of Science, Medicine and Health - Papers: part A

A concise synthesis of (−)-steviamine is reported along with the synthesis of its analogues 10-nor-steviamine, 10-nor-ent-steviamine and 5-epi-ent-steviamine. These compounds were tested against twelve glycosidases (at 143 μg mL−1 concentrations) and were found to have in general poor inhibitory activity against most enzymes. The 10-nor analogues however, showed 50–54% inhibition of α-L-rhamnosidase from Penicillium decumbens while one of these, 10-nor-steviamine, showed 51% inhibition of N-acetyl-β-D-glucosaminidase (from Jack bean) at the same concentration (760 μM).


Uv Photodissociation Action Spectroscopy Of Haloanilinium Ions In A Linear Quadrupole Ion Trap Mass Spectrometer, Christopher S. Hansen, Benjamin B. Kirk, Stephen J. Blanksby, Richard A. J O'Hair, Adam J. Trevitt Apr 2013

Uv Photodissociation Action Spectroscopy Of Haloanilinium Ions In A Linear Quadrupole Ion Trap Mass Spectrometer, Christopher S. Hansen, Benjamin B. Kirk, Stephen J. Blanksby, Richard A. J O'Hair, Adam J. Trevitt

Faculty of Science, Medicine and Health - Papers: part A

UV-vis photodissociation action spectroscopy is becoming increasingly prevalent because of advances in, and commercial availability of, ion trapping technologies and tunable laser sources. This study outlines in detail an instrumental arrangement, combining a commercial ion-trap mass spectrometer and tunable nanosecond pulsed laser source, for performing fully automated photodissociation action spectroscopy on gas-phase ions. The components of the instrumentation are outlined, including the optical and electronic interfacing, in addition to the control software for automating the experiment and performing online analysis of the spectra. To demonstrate the utility of this ensemble, the photodissociation action spectra of 4-chloroanilinium, 4-bromoanilinium, and 4-iodoanilinium cations ...


Switching Radical Stability By Ph-Induced Orbital Conversion, Ganna Gryn'ova, David L. Marshall, Stephen J. Blanksby, Michelle L. Coote Apr 2013

Switching Radical Stability By Ph-Induced Orbital Conversion, Ganna Gryn'ova, David L. Marshall, Stephen J. Blanksby, Michelle L. Coote

Faculty of Science, Medicine and Health - Papers: part A

In most radicals the singly occupied molecular orbital (SOMO) is the highest-energy occupied molecular orbital (HOMO); however, in a small number of reported compounds this is not the case. In the present work we expand significantly the scope of this phenomenon, known as SOMO–HOMO energy-level conversion, by showing that it occurs in virtually any distonic radical anion that contains a sufficiently stabilized radical (aminoxyl, peroxyl, aminyl) non-π-conjugated with a negative charge (carboxylate, phosphate, sulfate). Moreover, regular orbital order is restored on protonation of the anionic fragment, and hence the orbital configuration can be switched by pH. Most importantly, our ...


Five Practical Uses Of Spatial Autocorrelation For Studies Of Coral Reef Ecology, S Hamylton Mar 2013

Five Practical Uses Of Spatial Autocorrelation For Studies Of Coral Reef Ecology, S Hamylton

Faculty of Science, Medicine and Health - Papers: part A

The organisation of benthic communities across coral reefs is underpinned by spatially structured ecological processes and neighbourhood interactions such as larval dispersal, migration, competition and the spread of disease. These give rise to spatial autocorrelation in reef communities. This paper demonstrates how the measurement of spatial autocorrelation can profitably be incorporated into studies of coral reef ecology through a series of 5 simple statistical exercises: for the generation of maps depicting the strength of spatial relationships between ecological communities, as an indicator of optimal dimensions for sampling ecological communities on coral reefs, as a diagnostic tool for model misspecification, as ...


Biofabrication: An Overview Of The Approaches Used For Printing Of Living Cells, Cameron J. Ferris, Kerry G. Gilmore, Gordon G. Wallace, Marc In Het Panhuis Mar 2013

Biofabrication: An Overview Of The Approaches Used For Printing Of Living Cells, Cameron J. Ferris, Kerry G. Gilmore, Gordon G. Wallace, Marc In Het Panhuis

Faculty of Science, Medicine and Health - Papers: part A

The development of cell printing is vital for establishing biofabrication approaches as clinically relevant tools. Achieving this requires bio-inks which must not only be easily printable, but also allow controllable and reproducible printing of cells. This review outlines the general principles and current progress and compares the advantages and challenges for the most widely used biofabrication techniques for printing cells: extrusion, laser, microvalve, inkjet and tissue fragment printing. It is expected that significant advances in cell printing will result from synergistic combinations of these techniques and lead to optimised resolution, throughput and the overall complexity of printed constructs.


Carbon Dioxide Rebreathing In Respiratory Protective Devices: Influence Of Speech And Work Rate In Full-Face Masks, Carmen L. Smith, Jane L. Whitelaw, Brian Davies Mar 2013

Carbon Dioxide Rebreathing In Respiratory Protective Devices: Influence Of Speech And Work Rate In Full-Face Masks, Carmen L. Smith, Jane L. Whitelaw, Brian Davies

Faculty of Science, Medicine and Health - Papers: part A

Carbon dioxide (CO2) rebreathing has been recognised as a concern regarding respirator use and is related to symptoms of discomfort, fatigue, dizziness, headache, muscular weakness and drowsiness. Previous investigations are limited by small sample size and have not evaluated the relationship between CO2 inhalation and phonic respiration (breathing during speech) in respiratory protective devices (RPDs). A total of 40 workers trained in the use of RPDs performed a graded exercise test on a cycle ergonometer that increased in workload every 5 min. During the third minute of each stage, participants read aloud a prepared text. Measures of mixed expired CO2 ...


Diversifying Ethnicity In Australia's Population And Environment Debates, Natascha Klocker, Lesley Head Feb 2013

Diversifying Ethnicity In Australia's Population And Environment Debates, Natascha Klocker, Lesley Head

Faculty of Science, Medicine and Health - Papers: part A

Population–environment debates in Australia are at an impasse. While the ability of this continent to sustain more migrants has attracted persistent scrutiny, nuanced explorations of diverse migrant cultures and their engagements with Australian landscapes have scarcely begun. Yet as we face the challenges of a climate changing world we would undoubtedly benefit from the most varied knowledges we can muster. This paper brings together three arenas of environmental debate circulating in Australia—the immigration/carrying capacity debate, comparisons between Indigenous and Anglo-European modes of environmental interaction, and research on household sustainability dilemmas—to demonstrate the exclusionary tendencies of each ...


Welcome To Bogan-Ville: Reframing Class And Place Through Humour, Chris Gibson Feb 2013

Welcome To Bogan-Ville: Reframing Class And Place Through Humour, Chris Gibson

Faculty of Science, Medicine and Health - Papers: part A

On August 4, 2009, Australian online news commentary website the Punch announced that Albion Park, in the Australian industrial city of Wollongong, was one of the nation's top ten “most bogan” places. This paper explores what it means to be bogan in Australia, tracing historical antecedents, local debate at the time of this media event, and the manner in which the politics of class and place identity are negotiated through humour. Some local residents railed against associations with “lower-class” culture or feared damaged reputations for their neighbourhoods; others responded in sometimes unexpected and creative ways—through humour, and by ...


Effects Of Atmospheric Light Scattering On Spectroscopic Observations Of Greenhouse Gases From Space. Part 2: Algorithm Intercomparison In The Gosat Data Processing For Co2 Retrievals Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Paul O. Wennberg, Nicholas M. Deutscher, Debra Wunch, Geoffrey C. Toon, Yukio Yoshida, Christopher W. O'Dell, David Crisp, Charles E. Miller, Christian Frankenberg, Andre Butz, Ilse Aben, Sandrine Guerlet, Otto Hasekamp, Hartmut Boesch, Austin Cogan, Robert Parker, David Griffith, Ronald Macatangay, Justus Notholt, Ralf Sussmann, Markus Rettinger, Vanessa Sherlock, John Robinson, Esko Kyro, Pauli Heikkinen, Dietrich G. Feist, Isamu Morino, Nikolay Kadygrov, Dmitry Belikov, Shamil Maksyutov, Tsuneo Matsunaga, Osamu Uchino, Hiroshi Watanabe Feb 2013

Effects Of Atmospheric Light Scattering On Spectroscopic Observations Of Greenhouse Gases From Space. Part 2: Algorithm Intercomparison In The Gosat Data Processing For Co2 Retrievals Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Paul O. Wennberg, Nicholas M. Deutscher, Debra Wunch, Geoffrey C. Toon, Yukio Yoshida, Christopher W. O'Dell, David Crisp, Charles E. Miller, Christian Frankenberg, Andre Butz, Ilse Aben, Sandrine Guerlet, Otto Hasekamp, Hartmut Boesch, Austin Cogan, Robert Parker, David Griffith, Ronald Macatangay, Justus Notholt, Ralf Sussmann, Markus Rettinger, Vanessa Sherlock, John Robinson, Esko Kyro, Pauli Heikkinen, Dietrich G. Feist, Isamu Morino, Nikolay Kadygrov, Dmitry Belikov, Shamil Maksyutov, Tsuneo Matsunaga, Osamu Uchino, Hiroshi Watanabe

Faculty of Science, Medicine and Health - Papers: part A

This report is the second in a series of companion papers describing the effects of atmospheric light scattering in observations of atmospheric carbon dioxide (CO2) by the Greenhouse gases Observing SATellite (GOSAT), in orbit since 23 January 2009. Here we summarize the retrievals from six previously published algorithms; retrieving column-averaged dry air mole fractions of CO2 (XCO2) during 22 months of operation of GOSAT from June 2009. First, we compare data products from each algorithm with ground-based remote sensing observations by Total Carbon Column Observing Network (TCCON). Our GOSAT-TCCON coincidence criteria select satellite observations within a 5° radius of 11 ...


Dinosaur Lactation?, Paul L. Else Feb 2013

Dinosaur Lactation?, Paul L. Else

Faculty of Science, Medicine and Health - Papers: part A

Lactation is a process associated with mammals, yet a number of birds feed their newly hatched young on secretions analogous to the milk of mammals. These secretions are produced from various sections (crop organ, oesophageal lining and proventriculus) of the upper digestive tract and possess similar levels of fat and protein, as well as added carotenoids, antibodies and, in the case of pigeons and doves, epidermal growth factor. Parental care in avian species has been proposed to originate from dinosaurs. This study examines the possibility that some dinosaurs used secretory feeding to increase the rate of growth of their young ...


Sequential Extraction Procedures For The Determination Of Phosphorus Forms In Sediment, Changyou Wang, Yong Zhang, Hongli Li, R John Morrison Jan 2013

Sequential Extraction Procedures For The Determination Of Phosphorus Forms In Sediment, Changyou Wang, Yong Zhang, Hongli Li, R John Morrison

Faculty of Science, Medicine and Health - Papers: part A

This article summarizes the main extraction methods for sedimentary phosphorus (P) determination. With sequential chemical extractions, P is supposed to be selectively removed from different compounds in the sediments. Extraction schemes using strong acids and alkaline solutions have been tested on different sediments and found not to extract well-defined fractions. In addition, several systematic errors in these schemes have been detected. Thus, these schemes have been modified and simplified accordingly. The Standards Measurements and Testing Program of the European Commission (SMT) method is a popular modification of these extraction schemes, as it is simple to handle, allows laboratories to achieve ...


Single Molecule Characterization Of The Interactions Between Amyloid-Β Peptides And The Membranes Of Hippocampal Cells, Priyanka Narayan, Kristina A. Ganzinger, James Mccoll, Laura Weimann, Sarah Meehan, Seema Qamar, John A. Carver, Mark R. Wilson, Peter St George-Hyslop, Christopher M. Dobson, David Klenerman Jan 2013

Single Molecule Characterization Of The Interactions Between Amyloid-Β Peptides And The Membranes Of Hippocampal Cells, Priyanka Narayan, Kristina A. Ganzinger, James Mccoll, Laura Weimann, Sarah Meehan, Seema Qamar, John A. Carver, Mark R. Wilson, Peter St George-Hyslop, Christopher M. Dobson, David Klenerman

Faculty of Science, Medicine and Health - Papers: part A

Oligomers of the 40 and 42 residue amyloid-β peptides (Aβ40 and Aβ42) have been implicated in the neuronal damage and impaired cognitive function associated with Alzheimer’s disease. However, little is known about the specific mechanisms by which these misfolded species induce such detrimental effects on cells. In this work, we use single-molecule imaging techniques to examine the initial interactions between Aβ monomers and oligomers and the membranes of live cells. This highly sensitive method enables the visualization of individual Aβ species on the cell surface and characterization of their oligomerization state, all at biologically relevant, nanomolar concentrations. The results ...


Maternal Obesity Is Associated With The Formation Of Small Dense Ldl And Hypoadiponectinemia In The Third Trimester, Barbara J. Meyer, Frances M. Stewart, Elizabeth A. Brown, Josephine Cooney, Solveig Nilsson, Gunilla Olivecrona, Jane E. Ramsay, Bruce A. Griffin, Muriel J. Caslake, Dilys J. Freeman Jan 2013

Maternal Obesity Is Associated With The Formation Of Small Dense Ldl And Hypoadiponectinemia In The Third Trimester, Barbara J. Meyer, Frances M. Stewart, Elizabeth A. Brown, Josephine Cooney, Solveig Nilsson, Gunilla Olivecrona, Jane E. Ramsay, Bruce A. Griffin, Muriel J. Caslake, Dilys J. Freeman

Faculty of Science, Medicine and Health - Papers: part A

CONTEXT: Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL). HYPOTHESIS: In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase. DESIGN: Women (n = 55) of body mass index of 18-46 kg/m(2) were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally. SETTING: Women were recruited at hospital antenatal appointments, and study visits were in ...


Food Synergy: The Key To A Healthy Diet, David R. Jacobs Jr, Linda C. Tapsell Jan 2013

Food Synergy: The Key To A Healthy Diet, David R. Jacobs Jr, Linda C. Tapsell

Faculty of Science, Medicine and Health - Papers: part A

Food synergy is the concept that the non-random mixture of food constituents operates in concert for the life of the organism eaten and presumably for the life of the eater. Isolated nutrients have been extensively studied in well-designed, long-term, large randomised clinical trials, typically with null and sometimes with harmful effects. Therefore, although nutrient deficiency is a known phenomenon, serious for the sufferer, and curable by taking the isolated nutrient, the effect of isolated nutrients or other chemicals derived from food on chronic disease, when that chemical is not deficient, may not have the same beneficial effect. It appears that ...


Synthesis, Characterization, And Photophysics Of Oxadiazole- And Diphenylaniline-Substituted Re(I) And Cu(I) Complexes, Raphael Horvath, Michael G. Fraser, Scott A. Cameron, Allan G. Blackman, Pawel Wagner, David L. Officer, Keith C. Gordon Jan 2013

Synthesis, Characterization, And Photophysics Of Oxadiazole- And Diphenylaniline-Substituted Re(I) And Cu(I) Complexes, Raphael Horvath, Michael G. Fraser, Scott A. Cameron, Allan G. Blackman, Pawel Wagner, David L. Officer, Keith C. Gordon

Faculty of Science, Medicine and Health - Papers: part A

Transition-metal complexes of the types [Re(CO)3Cl(NN)], [Re(CO)3py(NN)]+, and [Cu(PPh3)2(NN)]+, where NN = 4,4′-bis(5-phenyl-1,3,4-oxadiazol-2-yl)-2,2′-bipyridine (OX) and 4,4′-bis(N,N-diphenyl-4-[ethen-1-yl]-aniline)-2,2′-bipyridine (DPA), have been synthesized and characterized. Crystal structures for [Re(CO)3Cl(DPA)] and [Cu(PPh3)2(OX)]BF4 are presented. The crystal structure of the rhenium complex shows a trans arrangement of the ethylene groups, in agreement with density functional theory calculations. The structure of the copper complex displays the planar aromatic nature of the bpy–oxadiazole ligand ...


Concise Synthesis Of Α-Substituted 2-Benzofuranmethamines And Other 2-Subsituted Benzofurans Via Α-Substituted 2-Benzofuranmethyl Carbocation Intermediates, Nikhom Wongsa, Ubonta Sommart, Thunwadee Ritthiwigrom, Arife Yazici, Somdej Kanokmedhakul, Kwanjai Kanokmedhakul, Anthony C. Willis, Stephen G. Pyne Jan 2013

Concise Synthesis Of Α-Substituted 2-Benzofuranmethamines And Other 2-Subsituted Benzofurans Via Α-Substituted 2-Benzofuranmethyl Carbocation Intermediates, Nikhom Wongsa, Ubonta Sommart, Thunwadee Ritthiwigrom, Arife Yazici, Somdej Kanokmedhakul, Kwanjai Kanokmedhakul, Anthony C. Willis, Stephen G. Pyne

Faculty of Science, Medicine and Health - Papers: part A

Propargyl amines 4, where R3 is aryl, undergo 5-exo-dig cyclization reactions under relatively mild conditions (AgNO3, DMF, 60 °C, 1 h) to give 3-amino-2,3-dihydro-2-arylmethylidenebenzofurans 5 (R3 = aryl). In contrast, substrates where R3 is alkyl undergo competing 6-endo-dig and 5-exo-dig cyclization processes. The hydroxymethyl substrate 4 (R3 = CH2OH), however, was smoothly converted to its corresponding 5-exo-dig cyclization product 5, likely due to the assistance of the primary hydroxyl group in the 5-exo-dig cyclization process by silver cation coordination. Under more enforcing conditions (AgNO3, DMF, 100 °C, 18 h), the initially formed products 5 undergo a 1,3-allylic rearrangement to their ...


Induced Pluripotent Stem Cells As Tools For Disease Modelling And Drug Discovery In Alzheimer's Disease, Lezanne Ooi, Kuldip Sidhu, Anne Poljak, Greg Sutherland, Michael D. O'Connor, Perminder Sachdev, Gerald Munch Jan 2013

Induced Pluripotent Stem Cells As Tools For Disease Modelling And Drug Discovery In Alzheimer's Disease, Lezanne Ooi, Kuldip Sidhu, Anne Poljak, Greg Sutherland, Michael D. O'Connor, Perminder Sachdev, Gerald Munch

Faculty of Science - Papers (Archive)

Alzheimer’s disease (AD) is a progressive neurodegenerative brain disorder that leads to a progressive decline in a person’s memory and ability to communicate and carry out daily activities. The brain pathology in AD is characterized by extensive neuronal loss, particularly of cholinergic neurons, intracellular neurofibrillary tangles composed of the tau protein (NFTs) and extracellular deposition of plaques composed of β-amyloid (Aβ), a cleavage product of the amyloid precursor protein (APP). These two insoluble protein aggregates are accompanied by a chronic inflammatory response and extensive oxidative damage. Whereas dys-regulation of APP expression or processing appears to be important for ...


A Reagentless Thermal Post-Synthetic Rearrangement Of An Allyloxy-Tagged Metal-Organic Framework, Andrew D. Burrows, Sally O. Hunter, Mary F. Mahon, Christopher Richardson Jan 2013

A Reagentless Thermal Post-Synthetic Rearrangement Of An Allyloxy-Tagged Metal-Organic Framework, Andrew D. Burrows, Sally O. Hunter, Mary F. Mahon, Christopher Richardson

Faculty of Science - Papers (Archive)

Direct heating of a metal-organic framework provides a simple, controllable way of effecting a covalent post-synthetic modification. Herein we report that an allyloxy-tagged zinc metal-organic framework undergoes a thermally-promoted aromatic Claisen rearrangement through which the framework connectivity and porosity are maintained.


Ten Trenches: A Scienceart Collaboration, Timothy J. Cohen, Martin Cohen, Stephanie Kermode, Michael G. Leggett Jan 2013

Ten Trenches: A Scienceart Collaboration, Timothy J. Cohen, Martin Cohen, Stephanie Kermode, Michael G. Leggett

Faculty of Science - Papers (Archive)

Collaborative and cross-disciplinary research by a group of artists and scientists in an Australian rural setting generates data and ideas that form the basis of a wider understanding of the ramifications of global warming and cooling within the local, regional and national community. The work is viewed as an initial educational platform that will allow the public to see and understand the complexities of climate-based research.


Two-Dimensional Cfd Modelling Of Gas-Decompression Behaviour, Alhoush Elshahomi, Cheng Lu, Guillaume Michal, Xiong Liu, Ajit R. Godbole, K K. Botros, Phillip Venton, Philip Colvin Jan 2013

Two-Dimensional Cfd Modelling Of Gas-Decompression Behaviour, Alhoush Elshahomi, Cheng Lu, Guillaume Michal, Xiong Liu, Ajit R. Godbole, K K. Botros, Phillip Venton, Philip Colvin

Faculty of Engineering and Information Sciences - Papers: Part A

ONE OF THE key issues in the design and construction of any gas pipeline is the prevention of material fracture. Since the gas is generally transported under high operating pressures, it must be ensured that the gas pipeline is sufficiently tough to arrest the propagation of any potential fracture. For several decades, control of gas pipeline fracture propagation has been under scrutiny due to economic considerations and ecological and safety hazards related to pressurised pipe failure. The Battelle Two Curve approach has been widely used to determine the minimum material arrest toughness by comparing the gas decompression wave velocity with ...


Practical Fabrication And Analysis Of An Optimized Compact Eight-Channel Silicon Arrayed-Waveguide Grating, Hongqiang Li, Yaoting Bai, Xiaye Dong, Enbang Li, Yang Li, Wenqian Zhou, Yu Liu Jan 2013

Practical Fabrication And Analysis Of An Optimized Compact Eight-Channel Silicon Arrayed-Waveguide Grating, Hongqiang Li, Yaoting Bai, Xiaye Dong, Enbang Li, Yang Li, Wenqian Zhou, Yu Liu

Faculty of Engineering and Information Sciences - Papers: Part A

We have designed, fabricated, and characterized a 1 x 8 ultrasmall compact arrayed-waveguide grating (AWG) on silicon-on-insulator (SOI) in a fiber grating demodulation integration microsystem. The miniature AWG, consisting of Si photonic wire waveguides, was designed using the complete modeling simulation in the beam propagation method. The device was fabricated on an SOI substrate and evaluated in the wavelength range around 1.55 μm, with an effective area of 230 x 160 μm. Clear demultiplexing characteristics were observed with a channel spacing of 1.91 nm. The influence of the waveguide widths on crosstalk defined by adjacent channel crosstalk and ...


Operations Strategy Processes: How Significant Are They?, Senevi Kiridena, Kalinga Jagoda, Howard Lin Jan 2013

Operations Strategy Processes: How Significant Are They?, Senevi Kiridena, Kalinga Jagoda, Howard Lin

Faculty of Engineering and Information Sciences - Papers: Part A

Ongoing challenges associated with the implementation of formally developed strategies call for studying the functional level strategy processes from fresh perspectives. This paper presents evidence drawn from the Canadian oil and gas industry towards establishing the statistical significance of alternative operations strategy processes and organisational contextual factors. The analysis discerned four strategy process configurations representing singular and multiple combinations of three strategy process modes identified in previous qualitative studies. The findings will help advance the understanding of operations strategy processes and may contribute to theory building, as the evidence was drawn from a relatively large sample of data representing an ...


Fabrication And Characterization Of A Polymer Micro-Fiber Bragg Grating, Ginu Rajan, Gang-Ding Peng Jan 2013

Fabrication And Characterization Of A Polymer Micro-Fiber Bragg Grating, Ginu Rajan, Gang-Ding Peng

Faculty of Engineering and Information Sciences - Papers: Part A

Polymer micro-fibers with inscribed Bragg gratings are reported in this paper. By implementing a two-stage fabrication process a 16 μm diameter micro-fiber is fabricated with an inscribed 10 mm long Bragg grating which exhibits a peak reflected wavelength circa 1530 nm. The growth dynamics of the polymer micro-fiber Bragg grating are also observed and analyzed. A maximum reflectivity of 5% is obtained after an exposure time of 3 minutes to a 50 mW power He-Cd laser of 325 nm wavelength. The temperature characterization of the micro-fiber Bragg grating with different diameters is also presented. The fabricated micro-fiber Bragg grating can ...


Response Of Substandard Reinforcing Details T Connections Upgraded With Concrete Covers And Cfrp, Tung M. Tran, B Matuszkiewicz, Muhammad N. S Hadi Jan 2013

Response Of Substandard Reinforcing Details T Connections Upgraded With Concrete Covers And Cfrp, Tung M. Tran, B Matuszkiewicz, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces the responses of two substandard reinforcing details exterior beam-column T connections, which were upgraded by a new retrofitting method using concrete covers and carbon fiber reinforced polymer (CFRP). Two reinforced concrete (RC) exterior beam-column connections without transverse reinforcement at the joints were cast and tested. A mix of epoxy resin and 20% thickener was used to glue the first connection (the Strengthened specimen, TS) with the concrete covers around the column at the joint area to modify it from a square to a circular section and then it was wrapped with CFRP to strengthen. A load was ...


Deposition Of Stellite 6 On Nickel Superalloy And Mild Steel Substrates With Laser Cladding, Alain Kusmoko, Druce P. Dunne, Huijun Li, David J. Nolan Jan 2013

Deposition Of Stellite 6 On Nickel Superalloy And Mild Steel Substrates With Laser Cladding, Alain Kusmoko, Druce P. Dunne, Huijun Li, David J. Nolan

Faculty of Engineering and Information Sciences - Papers: Part A

Stellite 6 was deposited by laser cladding of two different steel substrates (nickel superalloy and mild steel). The chemical compositions and microstructures of these coatings were characterized by atomic absorption spectroscopy, optical microscopy and scanning electron microscopy. The microhardness of the coatings was measured and the wear mechanism of the coatings was examined using a pin-on-plate (reciprocating) wear testing machine. The results showed less cracking and pore development for Stellite 6 coatings applied to the mild steel (MS) substrate. Further, the Stellite coating on mild steel was significantly harder than that deposited on the superalloy. The wear test results showed ...


Application Of Mbse To Requirements Engineering - Research Challenges, Mike Ryan, Stephen Cook, William R. Scott Jan 2013

Application Of Mbse To Requirements Engineering - Research Challenges, Mike Ryan, Stephen Cook, William R. Scott

Faculty of Engineering and Information Sciences - Papers: Part A

Models and simulations have always played an important role in engineering and systems engineering. Physical scale models, full-sized models, and computer models are commonly used in all forms of engineering and design. In recent times, interest in modelling has increased to span the full system lifecycle and there has been a significant focus on Model-based Systems Engineering (MBSE). The extension of formal modelling into all phases, and particularly the conceptual design phase, of a system development is a significant step and proponents of MBSE suggest that it will provide considerable benefits. The application of modelling requires considerable care, however. A ...


Effects Of Long-Distance Walking On Socket-Limb Interface Pressure, Tactile Sensitivity And Subjective Perceptions Of Trans-Tibial Amputees, L F. Yeung, Aaron Leung, Ming Zhang, Winson Lee Jan 2013

Effects Of Long-Distance Walking On Socket-Limb Interface Pressure, Tactile Sensitivity And Subjective Perceptions Of Trans-Tibial Amputees, L F. Yeung, Aaron Leung, Ming Zhang, Winson Lee

Faculty of Engineering and Information Sciences - Papers: Part A

PURPOSE: Many trans-tibial amputees could not tolerate long-distance walking. Lack of walking could explain for the increased cardiovascular diseases mortality rate. This study investigated the effects of long-distance walking (LDW) on socket-limb interface pressure, tactile sensitivity of the residual limb, and subjective feedbacks, which potentially identified the difficulties in LDW. METHOD: Five male unilateral trans-tibial amputees walked on a level treadmill for a total of one hour at comfortable speed. Tactile sensitivity of the residual limb and socket-limb interface pressure during over-ground walking were measured before and after the treadmill walking. Modified Prosthesis Evaluation Questionnaires were also administered. RESULTS: After ...