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Full-Text Articles in Social and Behavioral Sciences

Structural Insights Into The Dehydroascorbate Reductase Activity Of Human Omega-Class Glutathione Transferases, Huina Zhou, Joseph Brock, Dan Liu, Philip G. Board, Aaron J. Oakley Jan 2012

Structural Insights Into The Dehydroascorbate Reductase Activity Of Human Omega-Class Glutathione Transferases, Huina Zhou, Joseph Brock, Dan Liu, Philip G. Board, Aaron J. Oakley

Faculty of Science - Papers (Archive)

The reduction of dehydroascorbate (DHA) to ascorbic acid (AA) is a vital cellular function. The omega-class glutathione transferases (GSTs) catalyze several reductive reactions in cellular biochemistry, including DHA reduction. In humans, two isozymes (GSTO1-1 and GSTO2-2) with significant DHA reductase (DHAR) activity are found, sharing 64% sequence identity. While the activity of GSTO2-2 is higher, it is significantly more unstable in vitro. We report the first crystal structures of human GSTO2-2, stabilized through site-directed mutagenesis and determined at 1.9Å resolution in the presence and absence of glutathione (GSH). The structure of a human GSTO1-1 has been determined at 1.7Å resolution …


Synthesis, Properties And Water Permeability Of Swnt Buckypapers, L J. Sweetman, L Nghiem, I Chironi, G Triani, Marc In Het Panhuis, St F. Ralph Jan 2012

Synthesis, Properties And Water Permeability Of Swnt Buckypapers, L J. Sweetman, L Nghiem, I Chironi, G Triani, Marc In Het Panhuis, St F. Ralph

Faculty of Science - Papers (Archive)

The ability of macrocyclic ligands to facilitate formation of dispersions of single-walled carbon nanotubes (SWNTs) was investigated using a combination of absorption spectrophotometry and optical microscopy. Vacuum filtration of aqueous dispersions containing SWNTs and various macrocyclic ligands (derivatised porphyrin, phthalocyanine, cyclodextrin and calixarene) afforded self-supporting membranes known as buckypapers. Microanalytical data and energy dispersive X-ray spectra were obtained for these buckypapers and provided evidence for retention of the macrocyclic ligands within the structure of the membranes. The electrical conductivities of the membranes varied between 30 ± 20 and 220 ± 60 S cm−1, while contact angle analysis revealed they all …


Observed And Simulated Time Evolution Of Hcl, Clono2, And Hf Total Column Abundances, R Kohlhepp, R Ruhnke, M P Chipperfield, M De Maziere, J Notholt, S Barthlott, R L. Batchelor, R D. Blatherwick, Th Blumenstock, M T. Coffey, P Demoulin, H Fast, W Feng, A Goldman, D W. T Griffith, K Hamann, J W. Hannigan, F Hase, N B. Jones, A Kagawa, I Kaiser, Y Kasai, O Kirner, W Kouker, R Lindenmaier, E Mahieu, R L. Mittermeier, B Monge-Sanz, I Morino, I Murata, H Nakajima, M Palm, Clare Paton-Walsh, U Raffalski, Th Reddmann, M Rettinger, C P. Rinsland, E Rozanov, M Schneider, C Senten, C Servais, B M. Sinnhuber, D Smale, K Strong, R Sussmann, J R. Taylor, G Vanhaelewyn, T Warneke, C Whaley, M Wiehle, S W. Wood Jan 2012

Observed And Simulated Time Evolution Of Hcl, Clono2, And Hf Total Column Abundances, R Kohlhepp, R Ruhnke, M P Chipperfield, M De Maziere, J Notholt, S Barthlott, R L. Batchelor, R D. Blatherwick, Th Blumenstock, M T. Coffey, P Demoulin, H Fast, W Feng, A Goldman, D W. T Griffith, K Hamann, J W. Hannigan, F Hase, N B. Jones, A Kagawa, I Kaiser, Y Kasai, O Kirner, W Kouker, R Lindenmaier, E Mahieu, R L. Mittermeier, B Monge-Sanz, I Morino, I Murata, H Nakajima, M Palm, Clare Paton-Walsh, U Raffalski, Th Reddmann, M Rettinger, C P. Rinsland, E Rozanov, M Schneider, C Senten, C Servais, B M. Sinnhuber, D Smale, K Strong, R Sussmann, J R. Taylor, G Vanhaelewyn, T Warneke, C Whaley, M Wiehle, S W. Wood

Faculty of Science - Papers (Archive)

Time series of total column abundances of hydrogen chloride (HCl), chlorine nitrate (ClONO2), and hydrogen fluoride (HF) were determined from ground-based Fourier transform infrared (FTIR) spectra recorded at 17 sites belonging to the Network for the Detection of Atmospheric Composition Change (NDACC) and located between 80.05° N and 77.82° S. By providing such a near-global overview on ground-based measurements of the two major stratospheric chlorine reservoir species, HCl and ClONO2, the present study is able to confirm the decrease of the atmospheric inorganic chlorine abundance during the last few years. This decrease is expected following the 1987 Montreal Protocol and …


Sustained Solar Hydrogen Generation Using A Dye-Sensitised Nio Photocathode/Bivo4 Tandem Photo-Electrochemical Device, Lei Tong, Akihide Iwase, Andrew Nattestad, Udo Bach, Martin Weidelener, Gunther Gotz, Amaresh Mishra, Peter Bauerle, Rose Amal, Gordon G. Wallace, Attila J. Mozer Jan 2012

Sustained Solar Hydrogen Generation Using A Dye-Sensitised Nio Photocathode/Bivo4 Tandem Photo-Electrochemical Device, Lei Tong, Akihide Iwase, Andrew Nattestad, Udo Bach, Martin Weidelener, Gunther Gotz, Amaresh Mishra, Peter Bauerle, Rose Amal, Gordon G. Wallace, Attila J. Mozer

Faculty of Science - Papers (Archive)

Solar hydrogen generation sustained for at least several hours is demonstrated using a dye-sensitised nickel(II) oxide photocathode and BiVO4 photoanode connected in a tandem configuration. H2 evolution rate is 120 nmol h−1 (>80% faradaic efficiency) without electrical bias or sacrificial oxidant/reductant, at pH = 7 using visible light (>420 nm).


Remote Sensing Of Co2 And Ch4 Using Solar Absorption Spectrometry With A Low Resolution Spectrometer, C Petri, T Warneke, N Jones, T Ridder, J Messerschmidt, T Weinzierl, M Geibel, J Notholt Jan 2012

Remote Sensing Of Co2 And Ch4 Using Solar Absorption Spectrometry With A Low Resolution Spectrometer, C Petri, T Warneke, N Jones, T Ridder, J Messerschmidt, T Weinzierl, M Geibel, J Notholt

Faculty of Science - Papers (Archive)

Throughout the last few years solar absorption Fourier Transform Spectrometry (FTS) has been further developed to measure the total columns of CO2 and CH4. The observations are performed at high spectral resolution, typically at 0.02 cm(-1). The precision currently achieved is generally better than 0.25%. However, these high resolution instruments are quite large and need a dedicated room or container for installation. We performed these observations using a smaller commercial interferometer at its maximum possible resolution of 0.11 cm(-1). The measurements have been performed at Bremen and have been compared to observations using our high resolution instrument also situated at …


Properties Of The B+-H2 And B+-D2 Complexes: A Theoretical And Spectroscopic Study, B L. J Poad, V Dryza, A A. Buchachenko, J Kos, E J. Bieske Jan 2012

Properties Of The B+-H2 And B+-D2 Complexes: A Theoretical And Spectroscopic Study, B L. J Poad, V Dryza, A A. Buchachenko, J Kos, E J. Bieske

Faculty of Science - Papers (Archive)

The rotationally resolved infrared spectrum of the B+-D2 ion-neutral complex is recorded in the D-D stretch vibration region (2805–2875  cm−1) by detecting B+ photofragments. Analysis of the spectrum confirms a T-shaped equilibrium geometry for the B+-D2 complex with a vibrationally averaged intermolecular bond length of 2.247 Å, around 0.02 Å shorter than for the previously characterised B+-H2 complex [V. Dryza, B. L. J. Poad, and E. J. Bieske, J. Am. Chem. Soc. 130, 12986 (2008)10.1021/ja8018302]. The D-D stretch band centre occurs at 2839.76 ± 0.10 cm−1, representing a −153.8  cm−1 shift from the Q1(0) transition of the free D2 molecule. …


The Use Of Representative Species As Surrogates For Wetland Inundation, Kerrylee Rogers, Timothy J. Ralph, Neil Saintilan Jan 2012

The Use Of Representative Species As Surrogates For Wetland Inundation, Kerrylee Rogers, Timothy J. Ralph, Neil Saintilan

Faculty of Science - Papers (Archive)

The complex task of determining the inundation requirements of large floodplain wetlands is often simplified through the use of representative, umbrella or flagship species. This subset of species is targeted based on the assumption that their collective inundation requirements serve as a surrogate for the broader suite of species found within the wetland. We tested the application of representative species commonly used in wetland and water management planning in the Murray-Darling Basin. In a review of the water requirements of 155 plants and animals, we collated information on preferred inundation timing, duration, depth, rate of rise and fall, and inter-flood …


Book Review - Women In Leadership: Contextual Dynamics And Boundaries, Christine Eriksen Jan 2012

Book Review - Women In Leadership: Contextual Dynamics And Boundaries, Christine Eriksen

Faculty of Science - Papers (Archive)

Leadership scenarios and paradoxes - past, present and future - form the basis of Karin Klenke's analysis of women in leadership. The book sets out to explore the paradoxical nature of women's leadership in male-dominated contexts, paradoxes women leaders are confronted with, as well as the paradox of change versus the persistence of the status quo. Contexts with a 'paradoxical nature'- temporally and spatially - are at the forefront. These 'contexts' for women's leadership range from remarkable female leaders, today and historically, in politics, organisational structures, information technology (IT), the media, sports, the military, religion and spirituality, science, higher education …


Fatty And Volatile Oils Of The Gypsywort Lycopus Europaeus L. And The Gaussian-Like Distribution Of Its Wax Alkanes, Niko Radulovic, Marija Denic, Zorica Stojanovic-Radic, Danielle Skropeta Jan 2012

Fatty And Volatile Oils Of The Gypsywort Lycopus Europaeus L. And The Gaussian-Like Distribution Of Its Wax Alkanes, Niko Radulovic, Marija Denic, Zorica Stojanovic-Radic, Danielle Skropeta

Faculty of Science - Papers (Archive)

The detailed analyses of the volatile essential oil and lipid profiles of the aerial parts from the blooming and fruit-forming stages of both ripe and unripe fruit of Lycopus europaeus (Lamiaceae) are presented. Both of these profiles are distinguished by components with a restricted occurrence in the Plant Kingdom. These rare compounds include (E)-hotrienol in the volatiles, numerous unusual fatty acids (such as very long chain, odd-numbered and branched-chain) in the bound lipids and a high amount of iso- and anteiso-alkanes in the epicuticular waxes. Furthermore, a Gaussian-like distribution of the relative amounts of the epicuticular wax alkanes was observed. …


A Comparison Of Spatially Explicit And Classic Regression Modelling Of Live Coral Cover Using Hyperspectral Remote-Sensing Data In The Al Wajh Lagoon, Red Sea, S Hamylton Jan 2012

A Comparison Of Spatially Explicit And Classic Regression Modelling Of Live Coral Cover Using Hyperspectral Remote-Sensing Data In The Al Wajh Lagoon, Red Sea, S Hamylton

Faculty of Science - Papers (Archive)

Live coral is a key component of the Al Wajh marine reserve in the Red Sea. The management of this reserve is dependent on a sound understanding of the existing spatial distribution of live coral cover and the environmental factors influencing live coral at the landscape scale. This study uses remote-sensing techniques to develop ordinary least squares and spatially lagged autoregressive explanatory models of the distribution of live coral cover inside the Al Wajh lagoon, Saudi Arabia. Live coral was modelled as a response to environmental controls such as water depth, the concentration of suspended sediment in the water column …


The Awkward Spaces Of Fathering [Book Review], Ben Gallan Jan 2012

The Awkward Spaces Of Fathering [Book Review], Ben Gallan

Faculty of Science - Papers (Archive)

This review starts with PiriWeepu, the All Black and rugby world cup winner.An image depictingWeepu bottle-feeding his child was removed from a national anti-smoking advertisement in early 2012.What could be wrong with this tender moment between father and daughter? The image raised controversy because it conflicted with carefully scripted advertising campaigns promoting breastfeeding.


Conducting Sensitive Research In The Present And Past Tense: Recounting The Stories Of Current And Former Child Domestic Workers, Natascha Klocker Jan 2012

Conducting Sensitive Research In The Present And Past Tense: Recounting The Stories Of Current And Former Child Domestic Workers, Natascha Klocker

Faculty of Science - Papers (Archive)

In recent years, scholarship on children's work has increasingly incorporated the perspectives of working children. Although laudable, this shift toward children's inclusion in research has concentrated on those employed at the time of data collection. Former child workers have largely been overlooked as a source of information. This paper reflects on research conducted with current and former child domestic workers in Tanzania. The child domestic working experiences reported by those two groups diverged markedly: those who had already ceased employment reported far higher rates of dissatisfaction with child domestic work, and far more experiences of exploitation and abuse, than those …


The Atlas Of Women In The World [Book Review], Christine Eriksen Jan 2012

The Atlas Of Women In The World [Book Review], Christine Eriksen

Faculty of Science - Papers (Archive)

The Atlas ofWomen in theWorld is a resourceful book that instantly drew me in with its interesting choice of topics, vibrant colours and magnificent graphs. Joni Seager - an internationally acclaimed feminist geographer - highlights in the introduction that gender equality has yet to be attained around the world as well as what has actually improved for women since the first edition of the atlas was published in 1986.


Police Witness Identification Images: A Geometric Morphometric Analysis, Susan Hayes, Cameron Tullberg Jan 2012

Police Witness Identification Images: A Geometric Morphometric Analysis, Susan Hayes, Cameron Tullberg

Faculty of Science - Papers (Archive)

Research into witness identification images typically occurs within the laboratory and involves subjective likeness and recognizability judgments. This study analyzed whether actual witness identification images systematically alter the facial shapes of the suspects described. The shape analysis tool, geometric morphometrics, was applied to 46 homologous facial landmarks displayed on 50 witness identification images and their corresponding arrest photographs, using principal component analysis and multivariate regressions. The results indicate that compared with arrest photographs, witness identification images systematically depict suspects with lowered and medially located eyebrows (p=


Engaging With The (Un)Familiar: Field Teaching In A Multi-Campus Teaching Environment, Nicholas Gill, Michael Adams, Christine Eriksen Jan 2012

Engaging With The (Un)Familiar: Field Teaching In A Multi-Campus Teaching Environment, Nicholas Gill, Michael Adams, Christine Eriksen

Faculty of Science - Papers (Archive)

Field trips have long been central to geography, but have been subject to assessment of the role of the 'field' in teaching. At the same time, academics face barriers to running field trips. Distance education and enhanced educational access for non-metropolitan students represented such an obstacle at an Australian university. These obstacles were taken as an opportunity to draw on the regional nature of the students and staff to enhance teaching goals, run critically informed field trips by and manage academic workloads. We evaluate the field trips by conducting surveys and interviews with students and tutors, and as an example …


Investigating Arsenic Speciation And Mobilization In Sediments With Dgt And Det: A Mesocosm Evaluation Of Oxic-Anoxic Transitions, William W. Bennett, Peter R. Teasdale, Jarad G. Panther, David T. Welsh, Huijun Zhao, Dianne F. Jolley Jan 2012

Investigating Arsenic Speciation And Mobilization In Sediments With Dgt And Det: A Mesocosm Evaluation Of Oxic-Anoxic Transitions, William W. Bennett, Peter R. Teasdale, Jarad G. Panther, David T. Welsh, Huijun Zhao, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Mobilization of arsenic from freshwater and estuarine sediments during the transition from oxic to anoxic conditions was investigated using recently developed diffusive sampling techniques. Arsenic speciation and Fe(II) concentrations were measured at high resolution (1−3 mm) with in situ diffusive gradients in thin films (DGT) and diffusive equilibration in thin films (DET) techniques. Water column anoxia induced Fe(II) and As(III) fluxes from the sediment. A correlation between water column Fe(II) and As(III) concentrations was observed in both freshwater (rs = 0.896, p < 0.001) and estuarine (rs = 0.557, p < 0.001) mesocosms. Porewater sampling by DGT and DET techniques confirmed that arsenic mobilization was associated with the reductive dissolution of Fe(III) (hydr)oxides in the suboxic zone of the sediment; a relationship that was visible because of the ability to measure the coincident profiles of these species using combined DGT and DET samplers. The selective measurement of As(III) and total inorganic arsenic by separate DGT samplers indicated that As(III) was the primary species mobilized from the solid phase to the porewater. This measurement approach effectively ruled out substantial As(V) mobilization from the freshwater and estuarine sediments in this experiment. This study demonstrates the capabilities of the DGT and DET techniques for investigating arsenic speciation and mobilization over a range of sediment conditions.


The Extracellular Chaperone Clusterin Sequesters Oligomeric Forms Of The Amyloid-Beta 1-40 Peptide, Priyanka Narayan, Angel Orte, Richard W. Clarke, Benedetta Bolognesi, Sharon Hook, Kristina A. Ganzinger, Sarah Meehan, Mark R. Wilson, Christopher M. Dobson, David Klenerman Jan 2012

The Extracellular Chaperone Clusterin Sequesters Oligomeric Forms Of The Amyloid-Beta 1-40 Peptide, Priyanka Narayan, Angel Orte, Richard W. Clarke, Benedetta Bolognesi, Sharon Hook, Kristina A. Ganzinger, Sarah Meehan, Mark R. Wilson, Christopher M. Dobson, David Klenerman

Faculty of Science - Papers (Archive)

In recent genome-wide association studies, the extracellular chaperone protein, clusterin, has been identified as a newly-discovered risk factor in Alzheimer's disease. We have examined the interactions between human clusterin and the Alzheimer's disease-associated amyloid-β 1-40 peptide (Aβ 1-40), which is prone to aggregate into an ensemble of oligomeric intermediates implicated in both the proliferation of amyloid fibrils and in neuronal toxicity. Using highly sensitive single-molecule fluorescence methods, we have found that Aβ 1-40 forms a heterogeneous distribution of small oligomers (from dimers to 50-mers), all of which interact with clusterin to form long-lived, stable complexes. Consequently, clusterin is able …


Roles Of Extracellular Chaperones In Amyloidosis, Amy R. Wyatt, Justin J. Yerbury, Rebecca A. Dabbs, Mark R. Wilson Jan 2012

Roles Of Extracellular Chaperones In Amyloidosis, Amy R. Wyatt, Justin J. Yerbury, Rebecca A. Dabbs, Mark R. Wilson

Faculty of Science - Papers (Archive)

Extracellular protein misfolding and aggregation underlie many of the most serious amyloidoses including Alzheimer's disease, spongiform encephalopathies and type II diabetes. Despite this, protein homeostasis (proteostasis) research has largely focussed on characterising systems that function to monitor protein conformation and concentration within cells. We are now starting to identify elements of corresponding systems, including an expanding family of secreted chaperones, which exist in the extracellular space. Like their intracellular counterparts, extracellular chaperones are likely to play a central role in systems that maintain proteostasis; however, the precise details of how they participate are only just emerging. It is proposed that …


Synthesis Of Stemofoline Analogues As Acetylcholinesterase Inhibitors, Kwankamol Sastraruji, Thanapat Sastraruji, Alison T. Ung, Renate Griffith, Araya Jatisatienr, Stephen G. Pyne Jan 2012

Synthesis Of Stemofoline Analogues As Acetylcholinesterase Inhibitors, Kwankamol Sastraruji, Thanapat Sastraruji, Alison T. Ung, Renate Griffith, Araya Jatisatienr, Stephen G. Pyne

Faculty of Science - Papers (Archive)

Thirty two new stemofoline analogues were prepared from didehydrostemofoline for studies as AChE inhibitors. C-3 side-chain modified amino, carbamate, triazole and oxazole stemofoline derivatives were prepared. In general the amine derivatives were found to be stronger inhibitors of AChE than their alcohol analogues that we previously reported. Compounds 5 and 26, with small C-3 side chain substituents, were two of the most active inhibitors. Preliminary molecular docking studies suggested that these compounds may inhibit AChE by binding horizontally along the passage of the active-site gorge and block access to acetylcholine.


Changes In Forest Structure Over 60 Years: Tree Densities Continue To Increase In The Pilliga Forests, New South Wales, Australia, Robyn K. Whipp, I D. Lunt, Peter G. Spooner, Ross A. Bradstock Jan 2012

Changes In Forest Structure Over 60 Years: Tree Densities Continue To Increase In The Pilliga Forests, New South Wales, Australia, Robyn K. Whipp, I D. Lunt, Peter G. Spooner, Ross A. Bradstock

Faculty of Science - Papers (Archive)

"Studies of long-term vegetation changes are critical for enhancing our understanding of successional dynamics in natural ecosystems. Bycomparing forest inventory data from the 1940s against field data from 2005, we document changes in stand structure over 60 years in forests co-dominated by Callitris glaucophylla J. Thompson & L. Johnson, Allocasuarina luehmannii (R. Baker) L. Johnson and Eucalyptus crebra F.Muell., in central Pilliga, New South Wales (NSW), Australia. Sampling was stratified across two forest types and across a 1951 wildfire boundary, to assess the effects of initial stand structure and early disturbance on stand dynamics. Stems in the size range tallied …


Doing Participatory Action Research And Doing A Phd: Words Of Encouragement For Prospective Students, Natascha Klocker Jan 2012

Doing Participatory Action Research And Doing A Phd: Words Of Encouragement For Prospective Students, Natascha Klocker

Faculty of Science - Papers (Archive)

No abstract provided.


Atmospheric Tomography: A Bayesian Inversion Technique For Determining The Rate And Location Of Fugitive Emissions, Ruhi Humphries, Charles Jenkins, Ray Leuning, Steve Zegelin, David Griffith, Christopher Caldow, Henry Berko, Andrew Feitz Jan 2012

Atmospheric Tomography: A Bayesian Inversion Technique For Determining The Rate And Location Of Fugitive Emissions, Ruhi Humphries, Charles Jenkins, Ray Leuning, Steve Zegelin, David Griffith, Christopher Caldow, Henry Berko, Andrew Feitz

Faculty of Science - Papers (Archive)

A Bayesian inversion technique to determine the location and strength of trace gas emissions from a point source in open air is presented. It was tested using atmospheric measurements of N2O and CO2 released at known rates from a source located within an array of eight evenly spaced sampling points on a 20 m radius circle. The analysis requires knowledge of concentration enhancement downwind of the source and the normalized, three-dimensional distribution (shape) of concentration in the dispersion plume. The influence of varying background concentrations of ~1% for N2O and ~10% for CO2 was removed by subtracting upwind concentrations from …


Conducting Composite Materials From The Biopolymer Kappa-Carrageenan And Carbon Nanotubes, Ali Aldalbahi, Jin Chu, Peter Feng, Marc In Het Panhuis Jan 2012

Conducting Composite Materials From The Biopolymer Kappa-Carrageenan And Carbon Nanotubes, Ali Aldalbahi, Jin Chu, Peter Feng, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

Conducting composite films containing carbon nanotubes (CNTs) were prepared by using the biopolymer kappa-carrageenan (KC) as a dispersant. Rheological studies indicated that 0.5% w/v was the appropriate KC concentration for dispersing CNTs. Our results showed that multiwalled nanotubes (MWNTs) required less sonic energy than single-walled nanotubes (SWNTs) for the dispersion process to be complete. Films prepared by vacuum filtration exhibited higher conductivity and improved mechanical characteristics compared to those prepared by evaporative casting. All composite films displayed sensitivity to water vapour, but MWNT films were more sensitive than SWNT films.


Comparisons Of Observed And Modeled Oh And Ho 2 Concentrations During The Ambient Measurement Period Of The Hoxcomp Field Campaign, Y Kanaya, A Hofzumahaus, H-P Dorn, T Brauers, H Fuchs, F Holland, F Rohrer, B Bohn, R Tillmann, Rebekah Wegener, A Wahner, Y Kajii, K Miyamoto, S Nishida, K Watanabe, A Yoshino, Dagmar C. Kubistin, M Martinez, M Rudolf, H Harder, H Berresheim, T Elste, C Plass-Dulmer, G Stange, J Kleffmann, Y Elshorbany, U Schurath Jan 2012

Comparisons Of Observed And Modeled Oh And Ho 2 Concentrations During The Ambient Measurement Period Of The Hoxcomp Field Campaign, Y Kanaya, A Hofzumahaus, H-P Dorn, T Brauers, H Fuchs, F Holland, F Rohrer, B Bohn, R Tillmann, Rebekah Wegener, A Wahner, Y Kajii, K Miyamoto, S Nishida, K Watanabe, A Yoshino, Dagmar C. Kubistin, M Martinez, M Rudolf, H Harder, H Berresheim, T Elste, C Plass-Dulmer, G Stange, J Kleffmann, Y Elshorbany, U Schurath

Faculty of Science - Papers (Archive)

A photochemical box model constrained by ancillary observations was used to simulate OH and HO 2 concentrations for three days of ambient observations during the HOxComp field campaign held in Jülich, Germany in July 2005. Daytime OH levels observed by four instruments were fairly well reproduced to within 33% by a base model run (Regional Atmospheric Chemistry Mechanism with updated isoprene chemistry adapted from Master Chemical Mechanism ver. 3.1) with high R 2 values (0.72-0.97) over a range of isoprene (0.3-2 ppb) and NO (0.1-10 ppb) mixing ratios. Daytime HO 2(*) levels, reconstructed from the base model results taking into …


Channel Adjustments In Response To The Operation Of Large Dams: The Upper Reach Of The Lower Yellow River, Yuanxu Ma, He Qing Huang, Gerald C. Nanson, Yongi Li, Wenyi Yao Jan 2012

Channel Adjustments In Response To The Operation Of Large Dams: The Upper Reach Of The Lower Yellow River, Yuanxu Ma, He Qing Huang, Gerald C. Nanson, Yongi Li, Wenyi Yao

Faculty of Science - Papers (Archive)

The Yellow River in China carries an extremely large sediment load. River channel-form and lateral shifting in a dynamic, partly meandering and partly braided reach of the lower Yellow River, have been significantly influenced by construction of Sanmenxia Dam in 1960, Liujiaxia Dam in 1968, Longyangxia Dam in 1985 and Xiaolangdi Dam in 1997. Using observations from Huayuankou Station, 128 km downstream of Xiaolangdi Dam, this study examines changes in the river before and after construction of the dams. The temporal changes in the mean annual flow discharge and mean annual suspended sediment concentration have been strongly influenced by operation …


Development Of A Spatial Data Infrastructure For Coastal Management In The Amirante Islands, Seychelles, Sarah M. Hamylton, Justin Prosper Jan 2012

Development Of A Spatial Data Infrastructure For Coastal Management In The Amirante Islands, Seychelles, Sarah M. Hamylton, Justin Prosper

Faculty of Science - Papers (Archive)

Spatial data infrastructures play a key role in coastal management decision making in the Seychelles. This paper describes four components of a web-based spatial data infrastructure that were developed to facilitate coastal management of the Amirante Islands in the Seychelles. The four components include: (i) the institutional arrangement for using spatial data effectively to address local management challenges, (ii) the production of island habitat maps from remotely sensed data, (iii) the tasks undertaken for promoting access to and use of this spatial data, and (iv) an example of how this data is used for a specific coastal management application in …


Evidence Of Animal Mtdna Recombination Between Divergent Populations Of The Potato Cyst Nematode Globodera Pallida, Angelique H. Hoolahan, Vivian C. Blok, Tracey Gibson, Mark Dowton Jan 2012

Evidence Of Animal Mtdna Recombination Between Divergent Populations Of The Potato Cyst Nematode Globodera Pallida, Angelique H. Hoolahan, Vivian C. Blok, Tracey Gibson, Mark Dowton

Faculty of Science - Papers (Archive)

Recombination is typically assumed to be absent in animal mitochondrial genomes (mtDNA). However, the maternal mode of inheritance means that recombinant products are indistinguishable from their progenitor molecules. The majority of studies of mtDNA recombination assess past recombination events, where patterns of recombination are inferred by comparing the mtDNA of different individuals. Few studies assess contemporary mtDNA recombination, where recombinant molecules are observed as direct mosaics of known progenitor molecules. Here we use the potato cyst nematode, Globodera pallida, to investigate past and contemporary recombination. Past recombination was assessed within and between populations of G. pallida, and contemporary …


Electrical And Mechanical Characteristics Of Buckypapers And Evaporative Cast Films Prepared Using Single And Multi-Walled Carbon Nanotubes And The Biopolymer Carrageenan, Ali Aldalbahi, Marc In Het Panhuis Jan 2012

Electrical And Mechanical Characteristics Of Buckypapers And Evaporative Cast Films Prepared Using Single And Multi-Walled Carbon Nanotubes And The Biopolymer Carrageenan, Ali Aldalbahi, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

The electrical and mechanical characteristics of composite materials prepared using evaporative casting and vacuum filtration of carbon nanotubes (CNTs) dispersed in the biopolymer s-carrageenan (IC) are reported. It is demonstrated that the contact angle of water with films is proportional to the CNT mass and volume fraction, which is used to compare the properties of buckypapers with those of evaporative cast films. Multi-walled carbon nanotube films were found to exhibit higher conductivity values compared to those observed for single-walled carbon nanotubes composites at comparable contact angle values up to true nanotube volume fraction of 0.12. Buckypapers prepared by varying the …


Methane Retrievals From Greenhouse Gases Observing Satellite (Gosat) Shortwave Infrared Measurements: Performance Comparison Of Proxy And Physics Retrieval Algorithms, D Schepers, S Guerlet, A Butz, J Landgraf, C Frankenberg, O Hasekamp, J-F Blavier, N M. Deutscher, D W. T Griffith, F Hase, E Kyro, I Morino, V Sherlock, R Sussmann, I Aben Jan 2012

Methane Retrievals From Greenhouse Gases Observing Satellite (Gosat) Shortwave Infrared Measurements: Performance Comparison Of Proxy And Physics Retrieval Algorithms, D Schepers, S Guerlet, A Butz, J Landgraf, C Frankenberg, O Hasekamp, J-F Blavier, N M. Deutscher, D W. T Griffith, F Hase, E Kyro, I Morino, V Sherlock, R Sussmann, I Aben

Faculty of Science - Papers (Archive)

We compare two conceptually different methods for determining methane column-averaged mixing ratios (XCH4) from Greenhouse Gases Observing Satellite (GOSAT) shortwave infrared (SWIR) measurements. These methods account differently for light scattering by aerosol and cirrus. The proxy method retrieves a CO2 column which, in conjunction with prior knowledge on CO2 acts as a proxy for scattering effects. The physics-based method accounts for scattering by retrieving three effective parameters of a scattering layer. Both retrievals are validated on a 19-month data set using ground-based XCH4 measurements at 12 stations of the Total Carbon Column Observing Network (TCCON), …


Climate Change, Fuel And Fire Behaviour In A Eucalypt Forest, Stuart Matthews, Andrew L. Sullivan, Penny Watson, Richard J. Williams Jan 2012

Climate Change, Fuel And Fire Behaviour In A Eucalypt Forest, Stuart Matthews, Andrew L. Sullivan, Penny Watson, Richard J. Williams

Faculty of Science - Papers (Archive)

A suite of models was used to examine the links between climate, fuels and fire behaviour in dry eucalypt forests in south-eastern Australia. Predictions from a downscaled climate model were used to drive models of fuel amount, the moisture content of fuels and two models of forest fire behaviour at a location in western Sydney in New South Wales, Australia. We found that a warming and drying climate produced lower fine fuel amounts, but greater availability of this fuel to burn due to lower moisture contents. Changing fuel load had only a small effect on fuel moisture. A warmer, drier …