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2009

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Articles 5251 - 5280 of 7615

Full-Text Articles in Physical Sciences and Mathematics

Discrete Fractional Calculus With The Nabla Operator, Ferhan M. Atici, Paul W. Eloe Jan 2009

Discrete Fractional Calculus With The Nabla Operator, Ferhan M. Atici, Paul W. Eloe

Mathematics Faculty Publications

Properties of discrete fractional calculus in the sense of a backward difference are introduced and developed. Exponential laws and a product rule are developed and relations to the forward fractional calculus are explored. Properties of the Laplace transform for the nabla derivative on the time scale of integers are developed and a fractional finite difference equation is solved with a transform method. As a corollary, two new identities for the gamma function are exhibited.

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Mapping The Dark Side With Deimos: Globular Clusters, X-Ray Gas, And Dark Matter In The Ngc 1407 Group, Aaron J. Romanowsky, J. Strader, L. Spitler, R. Johnson, J. P. Brodie, D. A. Forbes, T. Ponman Jan 2009

Mapping The Dark Side With Deimos: Globular Clusters, X-Ray Gas, And Dark Matter In The Ngc 1407 Group, Aaron J. Romanowsky, J. Strader, L. Spitler, R. Johnson, J. P. Brodie, D. A. Forbes, T. Ponman

Aaron J. Romanowsky

NGC 1407 is the central elliptical in a nearby evolved group of galaxies apparently destined to become a galaxy cluster core. We use the kinematics of globular clusters (GCs) to probe the dynamics and mass profile of the group's center, out to a radius of 60 kpc (~10 galaxy effective radii)—the most extended data set to date around an early-type galaxy. This sample consists of 172 GC line-of-sight velocities, most of them newly obtained using Keck/DEIMOS, with a few additional objects identified as dwarf-globular transition objects or as intragroup GCs. We find weak rotation for the outer parts of the …

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The Planetary Nebula Spectrograph Elliptical Galaxy Survey: The Dark Matter In Ngc 4494, N. R. Napolitano, Aaron J. Romanowsky, L. Coccato, M. Capaccioli, N. G. Douglas, E. Noordermeer, O. Gerhard, M. Arnaboldi, F. De Lorenzi, K. Kuijken, M. R. Merrifield, E. O'Sullivan, A. Cortesi, P. Das, K. C. Freeman Jan 2009

The Planetary Nebula Spectrograph Elliptical Galaxy Survey: The Dark Matter In Ngc 4494, N. R. Napolitano, Aaron J. Romanowsky, L. Coccato, M. Capaccioli, N. G. Douglas, E. Noordermeer, O. Gerhard, M. Arnaboldi, F. De Lorenzi, K. Kuijken, M. R. Merrifield, E. O'Sullivan, A. Cortesi, P. Das, K. C. Freeman

Aaron J. Romanowsky

We present new Planetary Nebula Spectrograph observations of the ordinary elliptical galaxy NGC 4494, resulting in positions and velocities of 255 planetary nebulae out to seven effective radii (25 kpc). We also present new wide-field surface photometry from MMT/Megacam, and long-slit stellar kinematics from VLT/FORS2. The spatial and kinematical distributions of the planetary nebulae agree with the field stars in the region of overlap. The mean rotation is relatively low, with a possible kinematic axis twist outside 1Re. The velocity dispersion profile declines with radius, though not very steeply, down to ∼70 km s−1 at the last data point. We …

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Kinematic Properties Of Early-Type Galaxy Haloes Using Planetary Nebulae, L. Coccato, O. Gerhard, M. Arnaboldi, P. Das, N. G. Douglas, K. Kuijken, M. R. Merrifield, N. R. Napolitano, Aaron J. Romanowsky, E. Noordermeer, M. Capaccioli, A. Cortesi, F. De Lorenzi, K. C. Freeman Jan 2009

Kinematic Properties Of Early-Type Galaxy Haloes Using Planetary Nebulae, L. Coccato, O. Gerhard, M. Arnaboldi, P. Das, N. G. Douglas, K. Kuijken, M. R. Merrifield, N. R. Napolitano, Aaron J. Romanowsky, E. Noordermeer, M. Capaccioli, A. Cortesi, F. De Lorenzi, K. C. Freeman

Aaron J. Romanowsky

We present new planetary nebulae (PNe) positions, radial velocities and magnitudes for six early-type galaxies obtained with the Planetary Nebulae Spectrograph (PNS), along with derived two-dimensional velocity and velocity dispersion fields, and the α parameters (i.e. the number of PNe per unit luminosity). We also present new deep absorption-line long-slit kinematics for three galaxies in the sample, obtained with the FOcal Reducer and low dispersion Spectrograph (FORS2) at the Very Large Telescope (VLT). We extend this study to include additional 10 early-type galaxies with PNe radial velocity measurements available from the literature, including previous PNS studies, in order to obtain …

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Probing The 2d Kinematic Structure Of Early-Type Galaxies Out To 3 Effective Radii, R. N. Proctor, D. A. Forbes, J. P. Brodie, Aaron J. Romanowsky, J. Strader, M. Spolaor, J. T. Mendel, L. Spitler Jan 2009

Probing The 2d Kinematic Structure Of Early-Type Galaxies Out To 3 Effective Radii, R. N. Proctor, D. A. Forbes, J. P. Brodie, Aaron J. Romanowsky, J. Strader, M. Spolaor, J. T. Mendel, L. Spitler

Aaron J. Romanowsky

We detail an innovative new technique for measuring the two-dimensional (2D) velocity moments (rotation velocity, velocity dispersion and Gauss–Hermite coefficients h3 and h4) of the stellar populations of galaxy haloes using spectra from Keck DEIMOS (Deep Imaging Multi-Object Spectrograph) multi-object spectroscopic observations. The data are used to reconstruct 2D rotation velocity maps. Here we present data for five nearby early-type galaxies to ∼three effective radii. We provide significant insights into the global kinematic structure of these galaxies, and challenge the accepted morphological classification in several cases. We show that between one and three effective radii the velocity dispersion declines very …

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Central Mass-To-Light Ratios And Dark Matter Fractions In Early-Type Galaxies, C. Tortora, N. R. Napolitano, Aaron J. Romanowsky, M. Capaccioli, G. Covone Jan 2009

Central Mass-To-Light Ratios And Dark Matter Fractions In Early-Type Galaxies, C. Tortora, N. R. Napolitano, Aaron J. Romanowsky, M. Capaccioli, G. Covone

Aaron J. Romanowsky

Dynamical studies of local elliptical galaxies and the Fundamental Plane point to a strong dependence of the total mass-to-light ratio (M/L) on luminosity with a relation of the form M/L∝Lγ. The ‘tilt’γ may be caused by various factors, including stellar population properties (metallicity, age and star formation history), initial mass function, rotational support, luminosity profile non-homology and dark matter (DM) fraction. We evaluate the impact of all these factors using a large uniform data set of local early-type galaxies from Prugniel & Simien. We take particular care in estimating the stellar masses, using a general star formation history, and comparing …

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Dearth Of Dark Matter Or Massive Dark Halo? Mass-Shape-Anisotropy Degeneracies Revealed By Nmagic Dynamical Models Of The Elliptical Galaxy Ngc 3379, F. De Lorenzi, O. Gerhard, L. Coccato, M. Arnaboldi, M. Capaccioli, K. C. Freeman, K. Kuijken, M. R. Merrifield, N. R. Napolitano, E. Noordermeer, Aaron J. Romanowsky, V. P. Debattista Jan 2009

Dearth Of Dark Matter Or Massive Dark Halo? Mass-Shape-Anisotropy Degeneracies Revealed By Nmagic Dynamical Models Of The Elliptical Galaxy Ngc 3379, F. De Lorenzi, O. Gerhard, L. Coccato, M. Arnaboldi, M. Capaccioli, K. C. Freeman, K. Kuijken, M. R. Merrifield, N. R. Napolitano, E. Noordermeer, Aaron J. Romanowsky, V. P. Debattista

Aaron J. Romanowsky

Recent results from the Planetary Nebula Spectrograph (PNS) survey have revealed a rapidly falling velocity dispersion profile in the nearby elliptical galaxy NGC 3379, casting doubts on whether this intermediate-luminosity galaxy has the kind of dark matter (DM) halo expected in Λ cold dark matter (ΛCDM) cosmology. We present a detailed dynamical study of this galaxy, combining ground based long-slit spectroscopy, integral-field data from the Spectrographic Areal Unit for Research on Optical Nebulae (SAURON) instrument and PNS data reaching to more than seven effective radii. We construct dynamical models with the flexible χ2-made-to-measure (χ2M2M) particle method implemented in the NMAGIC …

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Kinematic Properties Of Early-Type Galaxy Haloes Using Planetary Nebulae, L. Coccato, O. Gerhard, M. Arnaboldi, P. Das, N. G. Douglas, K. Kuijken, M. R. Merrifield, N. R. Napolitano, Aaron J. Romanowsky, E. Noordermeer, M. Capaccioli, A. Cortesi, F. De Lorenzi, K. C. Freeman Jan 2009

Kinematic Properties Of Early-Type Galaxy Haloes Using Planetary Nebulae, L. Coccato, O. Gerhard, M. Arnaboldi, P. Das, N. G. Douglas, K. Kuijken, M. R. Merrifield, N. R. Napolitano, Aaron J. Romanowsky, E. Noordermeer, M. Capaccioli, A. Cortesi, F. De Lorenzi, K. C. Freeman

Faculty Publications

We present new planetary nebulae (PNe) positions, radial velocities and magnitudes for six early-type galaxies obtained with the Planetary Nebulae Spectrograph (PNS), along with derived two-dimensional velocity and velocity dispersion fields, and the α parameters (i.e. the number of PNe per unit luminosity). We also present new deep absorption-line long-slit kinematics for three galaxies in the sample, obtained with the FOcal Reducer and low dispersion Spectrograph (FORS2) at the Very Large Telescope (VLT). We extend this study to include additional 10 early-type galaxies with PNe radial velocity measurements available from the literature, including previous PNS studies, in order to obtain …

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Public Service Reform Through E-Government: A Case Study Of 'E-Tax' In Japan, Akemi T. Chatfield Jan 2009

Public Service Reform Through E-Government: A Case Study Of 'E-Tax' In Japan, Akemi T. Chatfield

Faculty of Informatics - Papers (Archive)

There is a growing interest in the debate over whether or not e-government has a transformational impact on government performance, governance, and public service, as we addressed this very issue at the 2007 ECEG. However, e-government research results on the transformational impact are mixed. This may be an apt reflection of either the early stages of e-government development or the newness of e-government research field or both. Our research goal as scholars of e-government must be to penetrate appearances to ascertain whatever lessons and meanings might lie beneath. This paper is an initial attempt toward achieving this goal. The main …

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Allocated Harmonic Quantities As The Basis For Source Detection, Timothy J. Browne, Sarath Perera, Victor J. Gosbell Jan 2009

Allocated Harmonic Quantities As The Basis For Source Detection, Timothy J. Browne, Sarath Perera, Victor J. Gosbell

Faculty of Informatics - Papers (Archive)

A considerable body of literature examines assessment, from measurements, of whether it is the network or a customer installation which makes the greater contribution to harmonic distortion at a point of common coupling. However, the customer contribution to harmonic distortion at a point of common coupling depends heavily upon the definition chosen for that contribution. For example, expressing contributions as currents instead of voltages or vice versa may lead to large changes in results. Further, it can be shown that the harmonic voltage at the point of common coupling cannot be expressed independently of the network conditions, meaning that the …

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E-Cheating, Online Sources And Technologies: A Critical Review Of Existing Literature, Zeenath Reza Khan, Stephen D. Samuel Jan 2009

E-Cheating, Online Sources And Technologies: A Critical Review Of Existing Literature, Zeenath Reza Khan, Stephen D. Samuel

Faculty of Informatics - Papers (Archive)

Being tech-savvy in the twenty-first century is no eye-brow raiser. It is more the norm than the exception. Every academic institution across borders is trying hard to keep up with the technology outside classroom, bringing it to the students inside classrooms to help and enhance their teaching and learning experience. While their achievements have been very well received and appreciated, the negative impacts have not gone totally ignored. From defining technology in the classrooms, to looking closely at cheating, how to detect them and curb them, a lot has been written by various authors in different disciplines. This paper, however, …

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Face Recognition From Single Sample Based On Human Face Perception, Ce Zhan, Wanqing Li, Philip Ogunbona Jan 2009

Face Recognition From Single Sample Based On Human Face Perception, Ce Zhan, Wanqing Li, Philip Ogunbona

Faculty of Informatics - Papers (Archive)

Although research show that human recognition performance for unfamiliar faces is relatively poor, when the sample is always available for analysis and becomes ”familiar”, people are able to recognize a previous unknown face from single sample. In this paper, a method is proposed to deal with the one sample per person face recognition problem based on the process how unfamiliar faces become familiar to people. Particularly, quantized local features which learnt from generic face dataset are used in the proposed method to mimic the prototype effect of human face recognition. Furthermore, a landmark-based scheme is introduced to quantify the distinctiveness …

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Face Detection Using Generalised Integral Image Features, Alister Cordiner, Philip Ogunbona, Wanqing Li Jan 2009

Face Detection Using Generalised Integral Image Features, Alister Cordiner, Philip Ogunbona, Wanqing Li

Faculty of Informatics - Papers (Archive)

This paper proposes generalised integral image features (GIIFs) for face detection. GIIFs provide a richer and more flexible set of features than Haar-like features. Due to the large set of possible GIIFs, a genetic algorithm is developed to select the feature space for the optimal weak classifiers. Experimental results have shown that this method is able to improve face detection accuracy.

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Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie Jan 2009

Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie

Faculty of Informatics - Papers (Archive)

In this article, we present a behind-the-scenes look at a Bayesian hierarchical analysis of pathways of exposure to arsenic (a toxic heavy metal) using the Phase I National Human Exposure Assessment Survey carried out in Arizona. Our analysis combines individual-level personal exposure measurements (biomarker and environmental media) with water, soil, and air observations from the ambient environment. We include details of our model-building exercise that involved a combination of exploratory data analysis and substantive knowledge in exposure science. Then we present our strategies for model fitting, which involved piecing together components of the hierarchical model in a systematic fashion to …

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An Efficient Certificateless Signature From Pairings, Changji Wang, Dongyang Long, Yong Tang Jan 2009

An Efficient Certificateless Signature From Pairings, Changji Wang, Dongyang Long, Yong Tang

Faculty of Informatics - Papers (Archive)

A certificateless signature retains the efficiency of Shamir's identity-based signature while it does not suffer from the inherent private key escrow problem, which is first introduced by S. Al-Riyami and K. Paterson in Asiacrypt 2003. In this paper, we proposed a new certificateless signature scheme based on bilinear pairings. The proposed scheme is more efficient than those of previous schemes by pre-computing the pairing e(P, P) = g and publishing as the system parameters, it needs not to compute the pairing in the Sign stage, and only needs to compute three pairings in the Verify stage. In addition, the proposed …

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A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser Jan 2009

A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser

Cyber Center Publications

Much data in the Web is hidden behind Web query interfaces. In most cases the only means to "surface" the content of a Web database is by formulating complex queries on such interfaces. Applications such as Deep Web crawling and Web database integration require an automatic usage of these interfaces. Therefore, an important problem to be addressed is the automatic extraction of query interfaces into an appropriate model. We hypothesize the existence of a set of domain-independent "commonsense design rules" that guides the creation of Web query interfaces. These rules transform query interfaces into schema trees. In this paper we …

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Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita Jan 2009

Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita

Cyber Center Publications

The emergence of mobile devices with Internet connectivity (e.g., Wi-Fi) and global positioning capabilities (e.g., GPS) have triggered the widespread development of location-based applications. For instance, users are able to ask queries about points of interest in their proximity. Furthermore, users can act as mobile sensors to monitor traffic flow, or levels of air pollution. However, such applications require users to disclose their locations, which raises serious privacy concerns. With knowledge of user locations, a malicious attacker can infer sensitive information, such as alternative lifestyles or political affiliations. Preserving location privacy is an essential requirement towards the successful deployment of …

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The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt Jan 2009

The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt

Cyber Center Publications

92 elements have been identified on earth and 17 of these are known to be essential to all plants. The essential elements required in relatively large amounts (>0.1% of dry mass) are called macronutrients and include C, H, O, N, S, P, Ca, K, Mg. Those required in much smaller amounts (<0.01% of dry mass) are referred to as micronutrients or trace elements and include Ni, Mo, Cu, Zn, Mn, B, Fe, and Cl. Plant growth and development depends on a balanced supply of these essential elements and thus the plant has a range of homeostatic mechanisms operating to ensure that this is maintained. Beneficial elements which promote growth and may be essential to some taxa, include Na, Co, Al, Se and Si. Elements such as the heavy metal Cd and the metalloid As have no demonstrated biological function in plants, but are nevertheless taken up and cause severe toxicity in most plant species. The concept for this special issue is the plant ionome, a word coined to encompass all these elements and allow focussed discussion and investigations on the mechanisms that co-ordinately regulate these elements in response to genetic and environmental factors reviewed in Salt et al., 2008).

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Foreword For The Special Issue Of Selected Papers From The 1st Acm Sigspatial Workshop On Security And Privacy In Gis And Lbs, Elisa Bertino, Maria Luisa Damiani Jan 2009

Foreword For The Special Issue Of Selected Papers From The 1st Acm Sigspatial Workshop On Security And Privacy In Gis And Lbs, Elisa Bertino, Maria Luisa Damiani

Cyber Center Publications

The first Workshop on Security and Privacy in GIS and LBS (SPRINGL 2008) was organized on November 4, 2008 at Irvine (CA) in conjunction with the SIGSPATIAL International Conference on Advances in Geographic Information Systems (ACM GIS 2008). The goal of the SPRINGL workshop series is to provide a forum for researchers working in the area of geospatial data security and privacy. Both security and privacy are critical for geospatial applications because of the dramatic increase and dissemination of geospatial data in several application contexts including homeland security, environmental crises, and natural and industrial disasters. Furthermore, geospatial infrastructures are being …

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Location Privacy In Moving-Object Environments, Dan Lin, Elisa Bertino, Reynold Cheng, Sunil Prabhakar Jan 2009

Location Privacy In Moving-Object Environments, Dan Lin, Elisa Bertino, Reynold Cheng, Sunil Prabhakar

Cyber Center Publications

The expanding use of location-based services has profound implications on the privacy of personal information. If no adequate protection is adopted, information about movements of specific individuals could be disclosed to unauthorized subjects or organizations, thus resulting in privacy breaches. In this paper, we propose a framework for preserving location privacy in moving-object environments. Our approach is based on the idea of sending to the service provider suitably modified location information. Such modifications, that include transformations like scaling, are performed by agents interposed between users and service providers. Agents execute data transformation and the service provider directly processes the transformed …

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The Small Heat-Shock Proteins Hspb2 And Hspb3 Form Well-Defined Heterooligomers In A Unique 3 To 1 Subunit Ratio, J. Den Engelsman, S. Baros, P. Y. W. Dankers, B. Kamps, W. T. Vree Egberts, C. S. Bode, L. A. Lane, J. A. Aquilina, J. L. P. Benesch, C. V. Robinson, W. W. De Jong, W. C. Boelens Jan 2009

The Small Heat-Shock Proteins Hspb2 And Hspb3 Form Well-Defined Heterooligomers In A Unique 3 To 1 Subunit Ratio, J. Den Engelsman, S. Baros, P. Y. W. Dankers, B. Kamps, W. T. Vree Egberts, C. S. Bode, L. A. Lane, J. A. Aquilina, J. L. P. Benesch, C. V. Robinson, W. W. De Jong, W. C. Boelens

Faculty of Science - Papers (Archive)

Various mammalian small heat-shock proteins (sHSPs) can interact with one another to form large polydisperse assemblies. In muscle cells, HSPB2/MKBP (myotonic dystrophy protein kinase-binding protein) and HSPB3 have been shown to form an independent complex. To date, the biochemical properties of this complex have not been thoroughly characterized. In this study, we show that recombinant HSPB2 and HSPB3 can be successfully purified from E.coli cells co-expressing both proteins. Nanoelectrospray ionization mass spectrometry and sedimentation velocity analytical ultracentrifugation analysis showed that HSPB2/B3 forms a series of well defined hetero-oligomers, consisting of 4, 8, 12, 16, 20 and 24 subunits, each maintaining …

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Towards Novel Entangled Carbon Nanotube Composite Electrodes, Gordon G. Wallace, P. Sherrell, J. Chen, A. Minett Jan 2009

Towards Novel Entangled Carbon Nanotube Composite Electrodes, Gordon G. Wallace, P. Sherrell, J. Chen, A. Minett

Faculty of Science - Papers (Archive)

The commercialization of carbon nanotube electrodes is impeded by the lack of bulk processing techniques. One approach to overcome this impediment is the growth of macroscopic CNT composite architectures which do not require any extra processing. Unfortunately the fundamental growth mechanisms of these carbon composites is not currently understood. To probe this mechanism a systematic examination of the effect of certain growth parameters was undertaken. Within this paper we present the promising preliminary findings of this study revealing extremely complex relationships between variables during growth. We also present the performance of the produced architectures as capacitor electrodes and the further …

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Testicular Descent, Sperm Maturation And Capacitation. Lessons From Our Most Distant Relatives, The Monotremes, Russell C. Jones, Heath Ecroyd, Jean-Louis Dacheux, Brett Nixon Jan 2009

Testicular Descent, Sperm Maturation And Capacitation. Lessons From Our Most Distant Relatives, The Monotremes, Russell C. Jones, Heath Ecroyd, Jean-Louis Dacheux, Brett Nixon

Faculty of Science - Papers (Archive)

The present review examines whether monotremes may help to resolve three questions relating to sperm production in mammals: why the testes descend into a scrotum in most mammals, why spermatozoa are infertile when they leave the testes and require a period of maturation in the specific milieu provided by the epididymides, and why ejaculated spermatozoa cannot immediately fertilise an ovum until they undergo capacitation within the female reproductive tract. Comparisons of monotremes with other mammals indicate that there is a need for considerable work on monotremes. It is hypothesised that testicular descent should be related to epididymal differentiation. Spermatozoa and …

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Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal Jan 2009

Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal

Faculty of Science - Papers (Archive)

The amorphous aggregation of proteins is associated with many phenomena, ranging from the formation of protein wine haze to the development of cataract in the eye lens and the precipitation of recombinant proteins during their expression and purification. While much literature exists describing models for linear protein aggregation, such as amyloid fibril formation, there are few reports of models which address amorphous aggregation. Here, we propose a model to describe the amorphous aggregation of proteins which is also more widely applicable to other situations where a similar process occurs, such as in the formation of colloids and nanoclusters. As first …

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Online Ozonolysis Methods For The Determination Of Double Bond Position In Unsaturated Lipids, Michael Thomas, Todd W. Mitchell, Stephen J. Blanksby Jan 2009

Online Ozonolysis Methods For The Determination Of Double Bond Position In Unsaturated Lipids, Michael Thomas, Todd W. Mitchell, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

Modern lipidomics relies heavily on mass spectrometry for the structural characterization and quantification of lipids of biological origins. Structural information is gained by tandem mass spectrometry (MS/MS) whereby lipid ions are fragmented to elucidate lipid class, fatty acid chain length, and degree of unsaturation. Unfortunately, however, in most cases double bond position cannot be assigned based on MS/MS data alone and thus significant structural diversity is hidden from such analyses. For this reason, we have developed two online methods for determining double bond position within unsaturated lipids; ozone electrospray ionization mass spectrometry (OzESI-MS) and ozone-induced dissociation (OzID). Both techniques utilize …

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Development And Application Of A System For The Analysis Of Atmospheric, Water And Sediment Nitrogen And Carbon, Ann Stavert, Stephen R. Wilson, Dianne F. Jolley Jan 2009

Development And Application Of A System For The Analysis Of Atmospheric, Water And Sediment Nitrogen And Carbon, Ann Stavert, Stephen R. Wilson, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Eutrophication and climate change, key environmental concerns, are both linked to the carbon and nitrogen cycles hence the improved understanding of these cycles is essential. Currently, there is no system that simultaneously measures the fluxes of the three key gas phase products of nitrogen and carbon cycling (CO2, CH4 and N2O) in submerged ecosystems with hourly time resolution. A “Lake-in-a-box” (mesocosm) was developed in the laboratory which allowed the monitoring of key components of the carbon and nitrogen cycles within the air, water and sediments. The approach is automated, simple and time efficient and novel in its ability to examine …

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The Effect Of Preparation Conditions And Biopolymer Dispersants On The Properties Of Swnt Buckypapers, Jenny Boge, Luke J. Sweetman, Marc In Het Panhuis, Stephen F. Ralph Jan 2009

The Effect Of Preparation Conditions And Biopolymer Dispersants On The Properties Of Swnt Buckypapers, Jenny Boge, Luke J. Sweetman, Marc In Het Panhuis, Stephen F. Ralph

Faculty of Science - Papers (Archive)

The effect of varying preparation conditions on the properties of buckypapers made using single-walled carbon nanotubes (SWNTs) was systematically investigated. Changing the sonication time, final dispersion volume or membrane filter used to prepare SWNT-Triton X-100 buckypapers all generally had only a small influence on the density, thickness, contact angle and electrical conductivity of the resulting material. More significant changes were noted when the effects of variations in the above preparation conditions on the mechanical properties and surface morphology of SWNT-Triton X-100 buckypapers were investigated. However, the largest changes in properties were found when various biopolymers (bovine serum albumin, lysozyme, gellan …

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Retrofitting The Suburban Garden: Morphologies And Some Elements Of Sustainability Potential Of Two Australian Residential Suburbs Compared, Sumita Ghosh, Lesley M. Head Jan 2009

Retrofitting The Suburban Garden: Morphologies And Some Elements Of Sustainability Potential Of Two Australian Residential Suburbs Compared, Sumita Ghosh, Lesley M. Head

Faculty of Science - Papers (Archive)

No abstract provided.

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

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

Faculty of Science - Papers (Archive)

No abstract provided.

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Reconstructing Annual Inflows To The Headwater Catchments Of The Murray River, Australia, Using The Pacific Decadal Oscillation, Hamish A. Mcgowan, Samuel K. Marx, John Denholm, Joshua Soderholm, Balz S. Kamber Jan 2009

Reconstructing Annual Inflows To The Headwater Catchments Of The Murray River, Australia, Using The Pacific Decadal Oscillation, Hamish A. Mcgowan, Samuel K. Marx, John Denholm, Joshua Soderholm, Balz S. Kamber

Faculty of Science - Papers (Archive)

The Pacific Decadal Oscillation (PDO) is a major forcing of inter-decadal to quasi-centennial variability of the hydroclimatology of the Pacific Basin. Its effects are most pronounced in the extra-tropical regions, while it modulates the El Nino Southern Oscillation (ENSO), the largest forcing of global inter-annual climate variability. PalaeoPDO indices are now available for at least the past 500 years. Here we show that the >500 year PDO index of Shen et al. (2006) is highly correlated with inflows to the headwaters of Australia's longest river system, the Murray-Darling. We then use the PDO to reconstruct annual inflows to the Murray …

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