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Full-Text Articles in Social and Behavioral Sciences

An Intercomparison Of Ground-Based Solar Ftir Measurements Of Atmospheric Gases At Eureka, Canada, Clare Paton-Walsh, R. Mittermeier, W. Bell, H. Fast, N. B. Jones, A. Meier Jan 2008

An Intercomparison Of Ground-Based Solar Ftir Measurements Of Atmospheric Gases At Eureka, Canada, Clare Paton-Walsh, R. Mittermeier, W. Bell, H. Fast, N. B. Jones, A. Meier

Faculty of Science - Papers (Archive)

We report the results of an intercomparison of vertical column amounts of hydrogen chloride (HCl), hydrogen fluoride (HF), nitrous oxide (N2O), nitric acid (HNO3), methane (CH4), ozone (O3), carbon dioxide (CO2) and nitrogen (N2) derived from the spectra recorded by two ground-based Fourier transform infrared (FTIR) spectrometers operated side-by-side using the sun as a source. The procedure used to record spectra and derive vertical column amounts follows the format of previous instrument intercomparisons organised by the Network for Detection of Atmospheric Composition Change (NDACC), formerly known as the Network for Detection of Stratospheric Change (NDSC). For most gases the differences …


New Cyclic Peptides Via Ring-Closing Metathesis Reactions And Their Anti-Bacterial Activities, Timothy P. Boyle, John B. Bremner, Jonathan Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, David I. Rhodes Jan 2008

New Cyclic Peptides Via Ring-Closing Metathesis Reactions And Their Anti-Bacterial Activities, Timothy P. Boyle, John B. Bremner, Jonathan Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, David I. Rhodes

Faculty of Science - Papers (Archive)

As part of a program investigating cyclic peptides with an internal aromatic hydrophobic scaffold as potential novel anti-bacterial agents, we explored the synthesis of simple tyrosine-based systems. These were prepared via key intermediates containing internal allylglycine and allyltyrosine residues for subsequent ring closing metathesis reactions. Although the resulting anti-bacterial activity against Staphylococcus aureus was modest, this represents a novel and simple route to this class of compounds. One intermediate acyclic dipeptide precursor showed good activity against S. aureus with an MIC of 7.8 µg/mL.


Foundational Myths: Country And Conservation In Australia, Michael Adams Jan 2008

Foundational Myths: Country And Conservation In Australia, Michael Adams

Faculty of Science - Papers (Archive)

In Australia, while each state has responsibility for the creation and management of their own national park systems, overall coordination is achieved through the Commonwealth National Reserve System. The Australian systems, like many others, are essentially based on the ‘Yellowstone model’ of protected areas: government owned and managed, precise boundaries, and with people present only as visitors or rangers (Stevens 1997). The Yellowstone model had its origins in wilderness protection, and despite many changes, wilderness persists as a foundational concept for Australian national parks.


Contentious Issues In Human-Wildlife Encounters: Seeking Solutions Ina Changing Social Context, Daniel Lunney, Adam J. Munn, Will Meikle Jan 2008

Contentious Issues In Human-Wildlife Encounters: Seeking Solutions Ina Changing Social Context, Daniel Lunney, Adam J. Munn, Will Meikle

Faculty of Science - Papers (Archive)

No abstract provided.


Mechanistic Explanations For Juvenile Kangaroo Moralities: Broad Implications For The Population Dynamics Of Large Herbivores During Climate Change, Adam J. Munn, Terence J. Dawson Jan 2008

Mechanistic Explanations For Juvenile Kangaroo Moralities: Broad Implications For The Population Dynamics Of Large Herbivores During Climate Change, Adam J. Munn, Terence J. Dawson

Faculty of Science - Papers (Archive)

Why do juvenile kangaroos die during drought? Answering this question is important because juvenile mortality typically drives whole population dynamics of large herbivores. To clarify reasons for the vulnerability of juveniles we investigated the ecophysiology of young red kangaroos (Macropus rufus), Australia’s largest marsupial herbivore. Compared with adults, juveniles had higher energy and water needs; these were related to requirements for growth and thermoregulation. Most importantly, juveniles could not maintain growth on poorer quality (high-fibre) forage due to an inability to expand gut-fill. Adults could adjust gut-fill to compensate, thereby increasing their survivability in dry conditions when easily digestible, low-fibre …


Approaches To Development Of A User-Friendly Community Based Arsenic/Iron Removal Unit In Bangladesh, Khondoker Mahabub Hassan, Farooque Ahmed, Faisal Ibney Hai, Saleh Faraj Magram Jan 2008

Approaches To Development Of A User-Friendly Community Based Arsenic/Iron Removal Unit In Bangladesh, Khondoker Mahabub Hassan, Farooque Ahmed, Faisal Ibney Hai, Saleh Faraj Magram

Faculty of Science - Papers (Archive)

The present stydy focuses on the strategies to modify the design of a community based Arsenic - Iron Removal Unit (AIRU) based on the field performance of the AIRU and the feedback from the users. The ultimate aim was to offer a user-friendly and sustainable system. Appropriate modifications in the design of the developed unit reduced the propensities of water head-loss and media clogging, thereby yielding sustained flow rate. Introduction of a simple cleaning procerdure (98% flow-recovery with three successive backwashing sequences) successfully reduced the frequency of requirement of labor-intensive replacement of the whole filter media. Raw water with arsenic …


Applied Conservation Management Of A Threatened Forest Dependant Frog, Heleioporus Australiacus, Trent D. Penman, F Lemckert, M J Mahony Jan 2008

Applied Conservation Management Of A Threatened Forest Dependant Frog, Heleioporus Australiacus, Trent D. Penman, F Lemckert, M J Mahony

Faculty of Science - Papers (Archive)

Threatened species management should be based on reliable scientific research. The giant burrowing frog Heleioporus australiacus is a threatened species in south-eastern Australia, and is often recorded on land managed for commercial forestry. As a result, management prescriptions have been developed in the absence of significant research data. Here, we review the available research data and assess the potential for forest management practices to impact upon this species. The species is restricted to naturally vegetated areas, but avoids steep areas, large rivers and forests with high levels of vegetative ground cover. Individuals spend the majority of the year in the …


Malonate-Bound Structure Of The Glycerophosphodiesterase From Enterobacter Aerogenes (Gpdq) And Characterization Of The Native Fe2+ Metal-Ion Preference, Colin J. Jackson, Kieran S. Hadler, Paul D. Carr, Aaron J. Oakley, Sylvia Yip, Gerhard Schenk, David L. Ollis Jan 2008

Malonate-Bound Structure Of The Glycerophosphodiesterase From Enterobacter Aerogenes (Gpdq) And Characterization Of The Native Fe2+ Metal-Ion Preference, Colin J. Jackson, Kieran S. Hadler, Paul D. Carr, Aaron J. Oakley, Sylvia Yip, Gerhard Schenk, David L. Ollis

Faculty of Science - Papers (Archive)

The structure of a malonate-bound form of the glycerophosphodiesterase from Enterobacter aerogenes, GpdQ, has been refined at a resolution of 2.2 A ̊ to a final R factor of 17.1%. The structure was originally solved to 2.9 A ̊ resolution using SAD phases from Zn2+ metal ions introduced into the active site of the apoenzyme [Jackson et al. (2007), J. Mol. Biol. 367, 1047–1062]. However, the 2.9 A ̊ resolution was insufficient to discern significant details of the architecture of the binuclear metal centre that constitutes the active site. Furthermore, kinetic analysis revealed that the enzyme lost a significant amount …


Ti-In-Zircon Thermometry Applied To Contrasting Archean Metamorphic And Igneous Systems, Joe Hiess, Allen Phillip Nutman, Vickie C. Bennett, Peter Holden Jan 2008

Ti-In-Zircon Thermometry Applied To Contrasting Archean Metamorphic And Igneous Systems, Joe Hiess, Allen Phillip Nutman, Vickie C. Bennett, Peter Holden

Faculty of Science - Papers (Archive)

Ti-in-zircon thermometry with SHRIMP II multi-collector has been applied to two well-documented Archean igneous and metamorphic samples from southern West Greenland. Zircons from 2.71 Ga partial melt segregation G03/38 formed in a small (<1 >m(3)), closed system within a mafic rock under high pressure granulite facies conditions. Results of 14 Ti analyses present a mean apparent zircon crystallization temperature of 679 +/- 11 degrees C, underestimating independent garnet-clinopyroxene thermometry by 20-50 degrees C but consistent with reduced a(TiO2) in this system. 36 spot analysis on 15 zircons from 3.81 Ga meta-tonalite G97/18, with an estimated magmatic temperature >1000 degrees C, …


Palaeoproterozoic And Archaean Gneiss Complexes In Northern Greenland: Palaeoproterozoic Terrane Assembly In The High Arctic, Allen Phillip Nutman, Peter Dawes, Feiko Kalsbeek, Mike Hamilton Jan 2008

Palaeoproterozoic And Archaean Gneiss Complexes In Northern Greenland: Palaeoproterozoic Terrane Assembly In The High Arctic, Allen Phillip Nutman, Peter Dawes, Feiko Kalsbeek, Mike Hamilton

Faculty of Science - Papers (Archive)

The Precambrian shield of northern Greenland has been investigated by SHRIMP U-Pb zircon dating of 14 orthogneisses and granitoids plus 5 metasediments, integrated with mapping by the Geological Survey of Denmark and Greenland and whole-rock Nd isotopic studies. The Inglefield Mobile Belt is a tract of Palaeoproterozoic sedimentation, plutonism, polyphase deformation and high-grade metamorphism that underlies Inglefield Land and northern Prudhoe Land. In the southern part of the belt at 78 degrees 30'N, the E-W-trending Sunrise Pynt Straight Belt is a high-grade, but structurally late, shear zone with contrasts in the geology on either side. South of the Sunrise Pynt …


Unraveling The Mysteries Of Protein Folding And Misfolding, Heath Ecroyd, John A. Carver Jan 2008

Unraveling The Mysteries Of Protein Folding And Misfolding, Heath Ecroyd, John A. Carver

Faculty of Science - Papers (Archive)

This mini-review focuses on the processes and consequences of protein folding and misfolding. The latter process often leads to protein aggregation and precipitation with the aggregates adopting either highly ordered (amyloid fibril) or disordered (amorphous) forms. In particular, the amyloid fibril is discussed because this form has gained considerable notoriety due to its close links to a variety of debilitating diseases including Alzheimer's, Parkinson's, Huntington's, and Creutzfeldt-Jakob diseases, and type-II diabetes. In each of these diseases a different protein forms fibrils, yet the fibrils formed have a very similar structure. The mechanism by which fibrils form, fibril structure, and the …


Dissociation From The Oligomeric State Is The Rate-Limiting Step In Fibril Formation By Kappa-Casein, Heath Ecroyd, Tomas Koudelka, David Thorn, Danielle M. Williams, Glyn Devlin, Peter Hoffmann, John A. Carver Jan 2008

Dissociation From The Oligomeric State Is The Rate-Limiting Step In Fibril Formation By Kappa-Casein, Heath Ecroyd, Tomas Koudelka, David Thorn, Danielle M. Williams, Glyn Devlin, Peter Hoffmann, John A. Carver

Faculty of Science - Papers (Archive)

Amyloid fibrils are aggregated and precipitated forms of protein in which the protein exists in highly ordered, long, unbranching threadlike formations that are stable and resistant to degradation by proteases. Fibril formation is an ordered process that typically involves the unfolding of a protein to partially folded states that subsequently interact and aggregate through a nucleation-dependent mechanism. Here we report on studies investigating the molecular basis of the inherent propensity of the milk protein, kappa-casein, to form amyloid fibrils. Using reduced and carboxymethylated kappa-casein ( RCM kappa-CN), we show that fibril formation is accompanied by a characteristic increase in thioflavin …


Instant Insight: Think Outside The Cell, Mark R. Wilson, Justin J. Yerbury Jan 2008

Instant Insight: Think Outside The Cell, Mark R. Wilson, Justin J. Yerbury

Faculty of Science - Papers (Archive)

Proteins perform many different functions critical for life, from building our muscle structure to digesting our food. These large biological molecules each have a unique three-dimensional shape which they require to perform their function. In protein deposition diseases (PDDs), however, a disease-specific protein molecule unfolds from its normal shape and assembles together with like molecules into insoluble rod-shaped fibrils. These protein deposits can be found in the brain, skeletal tissue and various organs; in some cases they may become large enough to disrupt tissue structure and function.


Chemical Event Tracking Using A Low-Cost Wireless Chemical Sensing Network, Stephen T. Beirne, B Corcoran, K T Lau, D Diamond Jan 2008

Chemical Event Tracking Using A Low-Cost Wireless Chemical Sensing Network, Stephen T. Beirne, B Corcoran, K T Lau, D Diamond

Faculty of Science - Papers (Archive)

A recently developed low-cost light emitting diode (LED) chemical sensing technique is integrated with a Mica2Dot wireless communications platform to form a deployable wireless chemical event indicator network. The operation of the colorimetric sensing node has been evaluated to determine its reproducibility and limit of detection for an acidic airborne contaminant. A test-scale network of five similar chemical sensing nodes is deployed in a star communication topology at fixed points within a custom built Environmental Sensing Chamber (ESC). Presented data sets collected from the deployed wireless chemical sensor network (WCSN) show that during an acidic event scenario it is possible …


Diastereoselective Ritter Reactions Of Chiral Cyclic N-Acyliminium Ions: Synthesis Of Pyrido- And Pyrrolo [2,3-D] Oxazoles And 4-Hydroxy-5-N-Acylaminopyrrolidines And 5-Hydroxy-6-N-Acylaminopiperidines, Ian R. Morgan, Arife Yazici, Stephen G. Pyne, Brian W. Skelton Jan 2008

Diastereoselective Ritter Reactions Of Chiral Cyclic N-Acyliminium Ions: Synthesis Of Pyrido- And Pyrrolo [2,3-D] Oxazoles And 4-Hydroxy-5-N-Acylaminopyrrolidines And 5-Hydroxy-6-N-Acylaminopiperidines, Ian R. Morgan, Arife Yazici, Stephen G. Pyne, Brian W. Skelton

Faculty of Science - Papers (Archive)

Pyrido- and pyrrolo[2,3-d]oxazoles can be conveniently prepared in high yield from the Ritter reaction of nitriles and in situ generated chiral cyclic N-acyliminium ions. cis-4-Hydroxy-5-acylaminopyrrolidines and cis-5-hydroxy-6-acylaminopiperidines can be readily obtained by acid hydrolysis of these bicyclic heterocyclic compounds, respectively.


On The Electrodeposition Of Titanium In Ionic Liquids, William E. Price, Gordon G. Wallace, Douglas Macfarlane, S Z. El Abedin, A Y. Saad, F Endres, E M. Moustafa, P J. Newman, A Bund, N Borissenko Jan 2008

On The Electrodeposition Of Titanium In Ionic Liquids, William E. Price, Gordon G. Wallace, Douglas Macfarlane, S Z. El Abedin, A Y. Saad, F Endres, E M. Moustafa, P J. Newman, A Bund, N Borissenko

Faculty of Science - Papers (Archive)

The ability to electrodeposit titanium at low temperatures would be an important breakthrough for making corrosion resistant layers on a variety of technically important materials. Ionic liquids have often been considered as suitable solvents for the electrodeposition of titanium. In the present paper we have extensively investigated whether titanium can be electrodeposited from its halides (TiCl4, TiF4, TiI4) in different ionic liquids, namely1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]Tf2N), 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl-sulfonyl)amide ([BMP]Tf2N), and trihexyltetradecyl-phosphonium bis(trifluoromethylsulfonyl)amide ([P14,6,6,6]Tf2N). Cyclic voltammetry and EQCM measurements show that, instead of elemental Ti, only non-stoichiometric halides are formed, …


A Naturally Occurring Mutation In Ropb Suppresses Speb Expression And Reduces M1t1 Group A Streptococcal Systemic Virulence, Andrew Hollands, Ramy K. Aziz, Rita G. Kansal, Malak Kotb, Victor Nizet, Mark J. Walker Jan 2008

A Naturally Occurring Mutation In Ropb Suppresses Speb Expression And Reduces M1t1 Group A Streptococcal Systemic Virulence, Andrew Hollands, Ramy K. Aziz, Rita G. Kansal, Malak Kotb, Victor Nizet, Mark J. Walker

Faculty of Science - Papers (Archive)

Epidemiological studies of group A streptococcus (GAS) have noted an inverse relationship between SpeB expression and invasive disease. However, the role of SpeB in the course of infection is still unclear. In this study we utilize a SpeB-negative M1T1 clinical isolate, 5628, with a naturally occurring mutation in the gene encoding the regulator RopB, to elucidate the role of RopB and SpeB in systemic virulence. Allelic exchange mutagenesis was used to replace the mutated ropB allele in 5628 with the intact allele from the well characterized isolate 5448. The inverse allelic exchange was also performed to replace the intact ropB …


Spectral And Spatial Variation At Leaf And Patch Scale Of Invasive Wetland Weeds, Laurie A. Chisholm, John K. Marthick Jan 2008

Spectral And Spatial Variation At Leaf And Patch Scale Of Invasive Wetland Weeds, Laurie A. Chisholm, John K. Marthick

Faculty of Science - Papers (Archive)

The establishment of invasive weeds in wetland environments is a prominent threat in Australia with adverse impacts on native flora. Current management is hindered by the lack of information available on which to base and justify management interventions, in particular, mapping of weed distributions. Remote sensing is a possible solution to difficulties of this type as illustrated by its successful application to wetland mapping in general. This paper explores the potential of multiscale spectral reflectance to discriminate between two particularly offensive, invasive woody weeds, bitou bush (Chrysanthemoides monilifera ssp rotundata), and lantana (Lantana camara). Spectral reflectance at …


Could A Big Gut Be Too Costly For Muskoxen (Ovibos Moschatus) In Their First Winter?, Adam J. Munn, Perry S. Barboza Jan 2008

Could A Big Gut Be Too Costly For Muskoxen (Ovibos Moschatus) In Their First Winter?, Adam J. Munn, Perry S. Barboza

Faculty of Science - Papers (Archive)

Young mammalian herbivores are more vulnerable to harsh winter conditions than adults, especially among large circumpolar species like the muskox (Ovibos moschatus). We compared feeding responses of muskox calves (body mass 95 kg) with those of mature, non-reproductive females (body mass 227 kg) in mid-winter when air temperatures fell to −40 °C. Food intakes (1.8–2.2 kg digestible dry matter (DM) d−1), digesta fill (27–32 kg wet mass) and digestibility of hay (52–58% of DM; 49–55% of gross energy) were similar between age groups even though calves were much smaller than adults. Calves fed more frequently (12 vs. 8 feeding bouts …


So, Where Is Queer? A Critical Geography Of Queer Exhibitions In Australia, Andrew W. Gorman-Murray Jan 2008

So, Where Is Queer? A Critical Geography Of Queer Exhibitions In Australia, Andrew W. Gorman-Murray

Faculty of Science - Papers (Archive)

This paper interrogates the geography of queer exhibitions in museums and galleries in Australia. The analysis draws on data from Museums Australia's database of queer exhibitions (1982-2005), which are cross-tabulated with geographical variables such as location, scale and state/territory population. The findings show an uneven geographical distribution of exhibitions, how geography also frames the themes of queer exhibitions, and an imbalanced geography, in which regional histories are few, national and state scale histories are prevalent, and minimal exhibitions occur outside metropolitan areas. This is problematic because queer identities, communities and histories vary across scales and between places. Appreciation of geography …


Strategic Roles Of Axial Histidines In Structure Formation And Redox Regulation Of Tetraheme Cytochrome C3, Y Takayama, N D Werbeck, H Komori, K Morita, Kiyoshi Ozawa, Y Higuchi, H Akutsu Jan 2008

Strategic Roles Of Axial Histidines In Structure Formation And Redox Regulation Of Tetraheme Cytochrome C3, Y Takayama, N D Werbeck, H Komori, K Morita, Kiyoshi Ozawa, Y Higuchi, H Akutsu

Faculty of Science - Papers (Archive)

Tetraheme cytochrome c3 (cyt c3) exhibits extremely low reduction potentials and unique properties. Since axial ligands should be the most important factors for this protein, every axial histidine of Desulfovibrio vulgaris Miyazaki F cyt c3 was replaced with methionine, one by one. On mutation at the fifth ligand, the relevant heme could not be linked to the polypeptide, revealing the essential role of the fifth histidine in heme linking. The fifth histidine is the key residue in the structure formation and redox regulation of a c-type cytochrome. A crystal structure has been obtained for only H25M cyt c3. The overall …


High Resolution Analysis Of Uranium And Thorium Concentration As Well As U-Series Isotope Distributions In A Neanderthal Tooth From Payre (Ardeche, France) Using Laser Ablation Icp-Ms, R. Grun, Maxime Aubert, Renaud C. Joannes-Boyau, M-H Moncel Jan 2008

High Resolution Analysis Of Uranium And Thorium Concentration As Well As U-Series Isotope Distributions In A Neanderthal Tooth From Payre (Ardeche, France) Using Laser Ablation Icp-Ms, R. Grun, Maxime Aubert, Renaud C. Joannes-Boyau, M-H Moncel

Faculty of Science - Papers (Archive)

We have mapped U (238U) and Th (232Th) elemental concentrations as well as U-series isotope distributions in a Neanderthal tooth from the Middle Palaeolithic site of Payre using laser ablation ICP-MS. The U-concentrations in an enamel section varied between 1 and 1500 ppb. The U-concentration maps show that U-migration through the external enamel surface is minute, the bulk of the uranium having migrated internally via the dentine into the enamel. The uranium migration and uptake is critically dependent on the mineralogical structure of the enamel. Increased U-concentrations are observed along lineaments, some of which are associated with cracks, and others …


The Nagssugtoqidian Orogen In South-East Greenland: Evidence For Paleoproterozoic Collision And Plate Assembly, Allen Phillip Nutman, Feiko Kalsbeek, Clark R L Friend Jan 2008

The Nagssugtoqidian Orogen In South-East Greenland: Evidence For Paleoproterozoic Collision And Plate Assembly, Allen Phillip Nutman, Feiko Kalsbeek, Clark R L Friend

Faculty of Science - Papers (Archive)

The 200 km wide, east-west trending Paleoproterozoic mobile belt of the Ammassalik region of South-East Greenland contains a diverse assemblage of Paleoproterozoic and Archean rocks, variably affected by Paleoproterozoic deformations and high-grade low or high pressure metamorphism. By using previous field and geochemical data combined with new zircon dating and zircon trace element geochemistry, this mobile belt is confirmed as a 1870 to 1840 Ma collisional orogen, which contains one or more 1900 to 1880 Ma magmatic suites and northern and southern Archean basement terranes. The most studied 1900 to 1880 Ma magmatic suite is the Ammassalik Intrusive Complex, which …


Images Of Diagenetic Textures In Porites Corals From Papua New Guinea And Indonesia, Helen V. Mcgregor, N J. Abram Jan 2008

Images Of Diagenetic Textures In Porites Corals From Papua New Guinea And Indonesia, Helen V. Mcgregor, N J. Abram

Faculty of Science - Papers (Archive)

Diagenesis is now recognized as a potentially major source of error in paleoclimatic reconstructions from fossil and modern coral geochemical records. Key to avoiding spurious results caused by diagenesis is thorough screening of coral material prior to geochemical analysis. In this data brief we present color images from thin sections of fossil and modern Porites corals and demonstrate the effectiveness of thin sections in detecting low levels of diagenesis. The images presented here cover a range of coral preservation levels from pristine aragonite to 100% calcite. We particularly focus on samples containing around 1% diagenetic material, a level known to …


Global Airs And Mopitt Co Measurements: Validation, Comparison, And Links To Biomass Burning Variations And Carbon Cycle, Leonid N. Yurganov, W. Wallace Mcmillan, Anatoly V. Dzhola, Evgeny I. Grechko, Nicholas B. Jones, Guido R. Van Der Werf Jan 2008

Global Airs And Mopitt Co Measurements: Validation, Comparison, And Links To Biomass Burning Variations And Carbon Cycle, Leonid N. Yurganov, W. Wallace Mcmillan, Anatoly V. Dzhola, Evgeny I. Grechko, Nicholas B. Jones, Guido R. Van Der Werf

Faculty of Science - Papers (Archive)

New results of CO global total column measurements using the Atmospheric Infrared Sounder (AIRS) aboard the Aqua satellite in comparison with Measurements of Pollution in the Troposphere (MOPITT) sensor aboard the Terra satellite are presented. Both data sets are validated using ground-based total column measurements in Russia and Australia. A quality parameter based on the Profile Percent A Priori values from the standard MOPITT product is introduced. AIRS data (version 4) for biomass burning events are in agreement or lower than both MOPITT and ground measurements, but CO bursts can be seen by AIRS in most cases. For the cases …


Impacts Of A Woody Invader Vary In Different Vegetation Communities, T J. Mason, K French Jan 2008

Impacts Of A Woody Invader Vary In Different Vegetation Communities, T J. Mason, K French

Faculty of Science - Papers (Archive)

The impact of an exotic species in natural systems may be dependent not only on invader attributes but also on characteristics of the invaded community. We examined impacts of the invader bitou bush, Chrysanthemoides monilifera ssp. rotundata , in fore and hind dune communities of coastal New South Wales, Australia. We compared invader impacts on vegetation structure, richness of both native and exotic growth forms and community variability in fore and hind dunes. We found that impacts of bitou invasion were context specific: in fore dune shrublands, functionally distinct graminoid, herb and climber rather than shrub growth forms had significantly …


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 …


Electrochemical Co-Deposition Of Tin+ Phases With Gold In Ionic Liquids, Jie Ding, Jian Wu, Douglas R. Macfarlane, William E. Price, Gordon G. Wallace Jan 2008

Electrochemical Co-Deposition Of Tin+ Phases With Gold In Ionic Liquids, Jie Ding, Jian Wu, Douglas R. Macfarlane, William E. Price, Gordon G. Wallace

Faculty of Science - Papers (Archive)

The electro-deposition of titanium from two different classes of ionic liquids has been studied. Gold ions in solution have been used as an additive in order to provide a stable nucleation site for titanium to deposit on via a co-deposition process. Despite evidence from previous literature, it was found that it was not possible to reduce titanium from the +4 state to titanium (0) due to problems of redox cycling and solubility of reduced titanium species in the various ILs trialled. It was however found that gold was a very effective nucleating agent for these reduced titanium species and that …


Sensor Response Of Polypyrrole Trilayer Benders As A Function Of Geometry, Stephen John, Gursel Alici, Geoffrey M. Spinks, John D. W. Madden, Gordon G. Wallace Jan 2008

Sensor Response Of Polypyrrole Trilayer Benders As A Function Of Geometry, Stephen John, Gursel Alici, Geoffrey M. Spinks, John D. W. Madden, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Trilayer polypyrrole benders are capable of generating voltages and currents when applied with an external force or displacement, demonstrating potential as mechanical sensors. Previous work has identified the effects of dopant and electrolyte on the sensor output, and a 'deformation induced ion flux' model was proposed. The current work aims to identify the change in sensor response with input amplitude and bender geometry as a function of frequency. The current and charge output from the trilayer benders were found to increase proportionally with input displacement and bender strain for multiple input frequencies, indicating linearity. Sensitivities of the current and charge …


Processable Aqueous Dispersions Of Graphene Nanosheets, Gordon G. Wallace, Richard B. Kaner, Marc Muller, Scott Gilje, Dan Li Jan 2008

Processable Aqueous Dispersions Of Graphene Nanosheets, Gordon G. Wallace, Richard B. Kaner, Marc Muller, Scott Gilje, Dan Li

Faculty of Science - Papers (Archive)

Graphene sheets offer extraordinary electronic, thermal and mechanical properties and are expected to find a variety of applications. A prerequisite for exploiting most proposed applications for graphene is the availability of processable graphene sheets in large quantities. The direct dispersion of hydrophobic graphite or graphene sheets in water without the assistance of dispersing agents has generally been considered to be an insurmountable challenge. Here we report that chemically converted graphene sheets obtained from graphite can readily form stable aqueous colloids through electrostatic stabilization. This discovery has enabled us to develop a facile approach to large-scale production of aqueous graphene dispersions …