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Measurements Of Oh Reactivity Using A Chemical Ionization Mass Spectrometry Technique, Joshua McGrath 2010 University of Colorado, Boulder

Measurements Of Oh Reactivity Using A Chemical Ionization Mass Spectrometry Technique, Joshua Mcgrath

Atmospheric & Oceanic Sciences Graduate Theses & Dissertations

Typically tropospheric chemical models overestimate [OH] when compared to measurements. This discrepancy is usually attributed to incompletely modeling OH sinks due to a lack of measurements. The determination of OH reactivity provides an independent means to quantify the overall contribution of these unmeasured trace species to OH oxidation. Therefore, a new instrument was developed to measure the total loss rate of OH to chemical species in ambient air using the CIMS technique.

Measurements were performed as part of two field campaigns, the Nucleation in Forests (NIFTy) study in Indiana during May 2008 and the Ocean-Atmosphere-Sea Ice- Snowpack (OASIS) Spring 2009 ...


Archaeological Evidence For Resilience Of Pacific Northwest Salmon Populations And The Socioecological System Over The Last ~7,500 Years, Sarah K. Campbell, Virginia L. Butler 2010 Western Washington University

Archaeological Evidence For Resilience Of Pacific Northwest Salmon Populations And The Socioecological System Over The Last ~7,500 Years, Sarah K. Campbell, Virginia L. Butler

Anthropology Faculty Publications and Presentations

Archaeological data on the long history of interaction between indigenous people and salmon have rarely been applied to conservation management. When joined with ethnohistoric records, archaeology provides an alternative conceptual view of the potential for sustainable harvests and can suggest possible social mechanisms for managing human behavior. Review of the ~7,500-year-long fish bone record from two subregions of the Pacific Northwest shows remarkable stability in salmon use. As major changes in the ecological and social system occurred over this lengthy period, persistence in the fishery is not due simply to a lack of perturbation, but rather indicates resilience in ...


Compositions Of Subsurface Ices At The Mars Phoenix Landing Site, Selby Cull, Raymond E. Arvidson, Michael T. Mellon, Philip Skemer, Amy Shaw, Richard V. Morris 2010 Bryn Mawr College

Compositions Of Subsurface Ices At The Mars Phoenix Landing Site, Selby Cull, Raymond E. Arvidson, Michael T. Mellon, Philip Skemer, Amy Shaw, Richard V. Morris

Geology Faculty Research and Scholarship

NASA's Phoenix Lander uncovered two types of ice at its 2008 landing site on the northern plains of Mars: a brighter, slab-like ice that broke during Robotic Arm operations; and a darker icy deposit. Spectra from the Phoenix Surface Stereo Imager (SSI) are used to demonstrate that the brighter material consists of nearly pure water ice, which probably formed by migration and freezing of liquid water. The darker icy material consists of similar to 30 +/- 20 wt% ice, with the remainder composed of fine-grained soil, indicating that it probably formed as pore ice. These two types of ice represent ...


Seasonal H2o And Co2 Ice Cycles At The Mars Phoenix Landing Site: 1. Prelanding Crism And Hirise Observations, Selby Cull, Raymond E. Arvidson, Michael Mellon, Sandra Wiseman, Roger Clark, Timothy Titus, Richard V. Morris, Patrick McGuire 2010 Bryn Mawr College

Seasonal H2o And Co2 Ice Cycles At The Mars Phoenix Landing Site: 1. Prelanding Crism And Hirise Observations, Selby Cull, Raymond E. Arvidson, Michael Mellon, Sandra Wiseman, Roger Clark, Timothy Titus, Richard V. Morris, Patrick Mcguire

Geology Faculty Research and Scholarship

The condensation, evolution, and sublimation of seasonal water and carbon dioxide ices were characterized at the Mars Phoenix landing site from Martian northern midsummer to midspring (Ls ∼ 142° – Ls ∼ 60°) for the year prior to the Phoenix landing on 25 May 2008. Ice relative abundances and grain sizes were estimated using data from the Compact Reconnaissance Imaging Spectrometer for Mars and High Resolution Imaging Science Experiment aboard Mars Reconnaissance Orbiter and a nonlinear mixing model. Water ice first appeared at the Phoenix landing site during the afternoon in late summer (Ls ∼ 167°) as an optically thin layer ...


Seasonal Ice Cycle At The Mars Phoenix Landing Site: 2. Postlanding Crism And Ground Observations, Selby Cull, R. E. Arvidson, R. V. Morris, M. Wolff, M. T. Mellon, M. T. Lemmon 2010 Bryn Mawr College

Seasonal Ice Cycle At The Mars Phoenix Landing Site: 2. Postlanding Crism And Ground Observations, Selby Cull, R. E. Arvidson, R. V. Morris, M. Wolff, M. T. Mellon, M. T. Lemmon

Geology Faculty Research and Scholarship

The combination of ground observations from the Mars Phoenix Lander and orbital data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) provided a detailed view of the formation of late summer surface water ice at the landing site and surrounding regions. CRISM observations of the landing site during and immediately after Phoenix operations were analyzed to track the seasonal and diurnal ice cycles during the late spring to late summer, and a nonlinear mixing model was used to estimate grain sizes and relative abundances of water ice and dust. The surface around the Phoenix landing site was ice-free from ...


2010-2011 Nova Southeastern University Undergraduate Student Catalog, Nova Southeastern University 2010 Nova Southeastern University

2010-2011 Nova Southeastern University Undergraduate Student Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.


Effect Of Two Types Of Tree Guards (With And Without Weed Control) On Tree Seedling Establishment, Brenton Ladd, Stephen P. Bonser, Joshua R. Larsen 2010 University of Bonn

Effect Of Two Types Of Tree Guards (With And Without Weed Control) On Tree Seedling Establishment, Brenton Ladd, Stephen P. Bonser, Joshua R. Larsen

Faculty of Science - Papers (Archive)

No abstract provided.


A Method For Monitoring Ink Homogeneity, Xinshi Luo, Siva Balakrishnan, Gerhard F. Swiegers 2010 Australian National University

A Method For Monitoring Ink Homogeneity, Xinshi Luo, Siva Balakrishnan, Gerhard F. Swiegers

Faculty of Science - Papers (Archive)

An important concern when developing new inks containing novel, bulk, solid-state additives is to ensure consistency during the printing process. In particular, the additives should not build up on the rollers, blankets or plates during printing. In this work we describe a method for detecting such events and quantitatively monitoring, in real time, the consistency of developmental inks during commercial printing processes. The technique employs a two-component mixture of emissive nanoparticles whose ratio becomes variable in a non-homogeneous environment. Even tiny variations in the ratio can be readily and dynamically detected in real time using a fibre-optic equipped fluorescence microspectrometer ...


Berberine-Inf55 (5-Nitro-2-Phenylindole) Hybrid Antimicrobials: Effects Of Varying The Relative Orientation Of The Berberine And Inf55 Components, Danuta Tomkiewicz, Gabriele Casadei, Jonah Larkins-Ford, Terence I. Moy, James A. Garner, John B. Bremner, Frederik M. Ausubel, Kim Lewis, Michael J. Kelso 2010 Northeastern Unversity, Boston

Berberine-Inf55 (5-Nitro-2-Phenylindole) Hybrid Antimicrobials: Effects Of Varying The Relative Orientation Of The Berberine And Inf55 Components, Danuta Tomkiewicz, Gabriele Casadei, Jonah Larkins-Ford, Terence I. Moy, James A. Garner, John B. Bremner, Frederik M. Ausubel, Kim Lewis, Michael J. Kelso

Faculty of Science - Papers (Archive)

Hybrid antimicrobials containing an antibacterial linked to a multidrug resistance (MDR) pump inhibitor make up a promising new class of agents for countering efflux-mediated bacterial drug resistance. This study explores the effects of varying the relative orientation of the antibacterial and efflux pump inhibitor components in three isomeric hybrids (SS14, SS14-M, and SS14-P) which link the antibacterial alkaloid and known substrate for the NorA MDR pump berberine to different positions on INF55 (5-nitro-2-phenylindole), an inhibitor of NorA. The MICs for all three hybrids against wild-type, NorA-knockout, and NorA-overexpressing Staphylococcus aureus cells were found to be similar (9.4 to 40 ...


Aerial ‘Oktokopter’ To Map Antarctic Moss, Arko Lucieer, Sharon A. Robinson, Dana Bergstrom 2010 University of Tasmania

Aerial ‘Oktokopter’ To Map Antarctic Moss, Arko Lucieer, Sharon A. Robinson, Dana Bergstrom

Faculty of Science - Papers (Archive)

Polar regions are experiencing rapid and severe climatic shifts with major changes in temperature, wind speed and UV-B radiation already observed in Antarctica. As climatic records only extend back 50 years, we urgently need new proxies to determine if coastal climate has changed over the past century.


The Effect Of Fuel Age On The Spread Of Fire In Sclerophyll Forest In The Sydney Region Of Australia., Ross A. Bradstock, Owen F. Price 2010 University of Wollongong

The Effect Of Fuel Age On The Spread Of Fire In Sclerophyll Forest In The Sydney Region Of Australia., Ross A. Bradstock, Owen F. Price

Faculty of Science - Papers (Archive)

We investigated the effect of fuel age on the truncation of spread of unplanned fires using a set of 1473 patches in the Sydney region of Australia. Twenty-two percent of patches derived from prescribed fire experienced a subsequent unplanned fire within 5 years, compared with 42% of patches derived from unplanned fires. Among those encounters, the subsequent unplanned fire stopped at the leading edge of 18% of prescribed patches and 11% of unplanned patches. In comparison, the subsequent fire stopped somewhere in the patch for 44% of both prescribed and unplanned fires. Overall, there was a 10% chance that a ...


Detection And Quantification Of Tear Phospholipids And Cholesterol In Contact Lens Deposits: The Effect Of Contact Lens Material And Lens Care Solution, Jennifer Saville, Zhenjun Zhao, Mark D.P. Willcox, Stephen J. Blanksby, Todd W. Mitchell 2010 University of Wollongong

Detection And Quantification Of Tear Phospholipids And Cholesterol In Contact Lens Deposits: The Effect Of Contact Lens Material And Lens Care Solution, Jennifer Saville, Zhenjun Zhao, Mark D.P. Willcox, Stephen J. Blanksby, Todd W. Mitchell

Faculty of Science - Papers (Archive)

PURPOSE. To examine the deposition of tear phospholipids and cholesterol onto worn contact lenses and the effect of lens material and lens care solution. METHODS. Lipids were extracted from tears and worn contact lenses using 2: 1 chloroform: methanol and the extract washed with aqueous ammonium acetate, before analysis by electrospray ionization tandem mass spectrometry (ESI-MS/MS). RESULTS. Twenty-three molecular lipids from the sphingomyelin (SM) and phosphatidylcholine (PC) classes were detected in tears, with total concentrations of each class determined to be 5 +/- 1 pmol/mu L (similar to 3.8 mu g/mL) and 6 +/- 1 pmol/mu L ...


A Mass Spectrometric Investigation Of Novel Quadruplex Dna-Selective Berberine Derivatives, Karina Gornall, Siritron Samosorn, Bongkot Tanwirat, Apichart Suksamrarn, John B. Bremner, Michael J. Kelso, Jennifer L. Beck 2010 University of Wollongong

A Mass Spectrometric Investigation Of Novel Quadruplex Dna-Selective Berberine Derivatives, Karina Gornall, Siritron Samosorn, Bongkot Tanwirat, Apichart Suksamrarn, John B. Bremner, Michael J. Kelso, Jennifer L. Beck

Faculty of Science - Papers (Archive)

ESI mass spectrometry was used to assess the binding of 13-substituted, 5-nitro-2-phenylindolyl- and 2-naphthalenyl-based berberine derivatives to inter- and intramolecular G-quadruplex DNA molecules. In contrast with the parent berberine, the compounds showed selectivity for quadruplex over duplex DNA and stabilised the quadruplex structure. They represent a new class of quadruplex DNA-selective ligands. © 2010 The Royal Society of Chemistry.


Crosslinking Neat Ultrathin Films And Nanofibres Of Ph-Responsive Poly(Acrylic Acid) By Uv Radiation, Adrian Gestos, Philip G. Whitten, Geoffrey Maxwell Spinks, Gordon G. Wallace 2010 University of Wollongong

Crosslinking Neat Ultrathin Films And Nanofibres Of Ph-Responsive Poly(Acrylic Acid) By Uv Radiation, Adrian Gestos, Philip G. Whitten, Geoffrey Maxwell Spinks, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Electrospun polyelectrolyte hydrogel nanofibres are being developed for many applications including artificial muscles, scaffolds for tissue engineering, wound dressings and controlled drug release. For electrospun polyelectrolytes, a post-spinning crosslinking process is necessary for producing a hydrogel. Typically, radiation or thermal crosslinking routines are employed that require multifunctional crosslinking molecules and crosslink reaction initiators (free radical producers). Here, ultraviolet subtype-C (UVC) radiation was employed to crosslink neat poly(acrylic acid) (PAA) nanofibres and films to different crosslink densities. Specific crosslink initiators or crosslinking molecules are not necessary in this fast and simple process providing an advantage for biological applications. Scanning probe ...


Dipyridyl Beta-Diketonate Complexes: Versatile Polydentate Metalloligands For Metal-Organic Frameworks And Hydrogen-Bonded Networks, Andrew D. Burrows, Christopher G. Frost, Mary F. Mahon, Paul R. Raithby, Catherine L. Renouf, Christopher Richardson, Anna J. Stevenson 2010 University of Bath

Dipyridyl Beta-Diketonate Complexes: Versatile Polydentate Metalloligands For Metal-Organic Frameworks And Hydrogen-Bonded Networks, Andrew D. Burrows, Christopher G. Frost, Mary F. Mahon, Paul R. Raithby, Catherine L. Renouf, Christopher Richardson, Anna J. Stevenson

Faculty of Science - Papers (Archive)

The Group 13 metal complexes [M(L-2)(3)], where M is Al or Ga and L-2 is 1,3-di(4-pyridyl)-1,3-propanedionato, are hexatopic metalloligands that have been used to prepare mixed-metalorganic frameworks containing interpenetrated primitive cubic networks. In contrast, the europium complex [Eu(HL2)(3)-(H2L2)]Cl-4 center dot EtOH forms a hydrogen-bonded network following partial protonation of the pyridyl groups.


The Dissociated Form Of Kappa-Casein Is The Precursor To Its Amyloid Fibril Formation, Heath Ecroyd, David Thorn, Yanqin Liu, John Carver 2010 University of Wollongong

The Dissociated Form Of Kappa-Casein Is The Precursor To Its Amyloid Fibril Formation, Heath Ecroyd, David Thorn, Yanqin Liu, John Carver

Faculty of Science - Papers (Archive)

Bovine milk kappa-casein forms a self-associating oligomeric micelle-like species, in equilibrium with dissociated forms. In its native form, intra- and inter-molecular disulfide bonds lead to the formation of multimeric species ranging from monomers to decamers. When incubated under conditions of physiological pH and temperature, both reduced and non-reduced kappa-casein form highly structured beta-sheet amyloid fibrils. We investigated whether the precursor to kappa-casein fibril formation is a dissociated state of the protein or its oligomeric micelle-like form. We show that reduced kappa-casein is capable of forming fibrils well below its critical micelle concentration, i.e. at concentrations where only dissociated forms ...


Carbon Nanotube Architectures As Catalyst Supports For Proton Exchange Membrane Fuel Cells, Weimin Zhang, Peter Sherrell, Andrew I. Minett, Joselito M. Razal, Jun Chen 2010 University of Wollongong

Carbon Nanotube Architectures As Catalyst Supports For Proton Exchange Membrane Fuel Cells, Weimin Zhang, Peter Sherrell, Andrew I. Minett, Joselito M. Razal, Jun Chen

Faculty of Science - Papers (Archive)

Catalyst support materials exhibit great influence on the performance and durability of proton exchange membrane (PEM) fuel cells. This minireview article summarises recent developments into carbon nanotube-based support materials for PEM fuel cells, including the membrane electrode assembly (MEA). The advantages of using CNTs to promote catalyst performance and stability, a perspective on research directions and strategies to improve fuel cell performance and durability are discussed. It is hoped that this mini-review will act as a conduit for future developments in catalyst supports and MEA design for PEM fuel cells.


Advanced Microwave-Assisted Production Of Hybrid Electrodes For Energy Applications, Peter Sherrell, Jun Chen, Joselito M. Razal, Ivan P. Nevirkovets, Carol Crean, Andrew I. Minett, Gordon G. Wallace 2010 University of Wollongong

Advanced Microwave-Assisted Production Of Hybrid Electrodes For Energy Applications, Peter Sherrell, Jun Chen, Joselito M. Razal, Ivan P. Nevirkovets, Carol Crean, Andrew I. Minett, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Carbon nanotubes are one of the most prominent materials in research for creating electrodes for portable electronics. When coupled with metallic nanoparticles the performance of carbon nanotube electrodes can be dramatically improved. Microwave reduction is an extremely rapid method for producing carbon nanotube-metallic nanoparticle composites, however this technique has so far been limitied to carbon nanotube soot. An understanding of the microwave process and the interactions of metallic nanoparticles with carbon nanotubes has allowed us to extend this promising functionalisation route to pre-formed CNT elelctrode architectures. Nanoparticle reduction onto pre-formed architectures reduces metallic nanoparticle waste as particles are not formed ...


Casey: The Daintree Of Antarctica, Dana Bergstrom, Sharon A. Robinson 2010 Australian Antarctic Division

Casey: The Daintree Of Antarctica, Dana Bergstrom, Sharon A. Robinson

Faculty of Science - Papers (Archive)

Antarctica is at the edge of life on the planet. Less than 0.5% of the Antarctic continent is ice-free rock or soil and therefore only tiny pockets of land are available for plants to establish. The Australian Antarctic Territory is home to some of the rarest ecosystems on the planet and the plant life at Casey is as good as it gets - Casey has the most extensive and best developed plant communities in continental Antarctica: it is the 'Daintree' of Antarctica. The largest plants are the mosses and they are like miniature old growth forests, growing incredibly slowly. A ...


In Vivo Measurement Of Plant Respiration, M. Ribas-Carbo, J. Flexas, Sharon A. Robinson, G. G.B. Tcherkez 2010 Universitat de les Illes Balears, Spain

In Vivo Measurement Of Plant Respiration, M. Ribas-Carbo, J. Flexas, Sharon A. Robinson, G. G.B. Tcherkez

Faculty of Science - Papers (Archive)

Respiration is vital; it is the essence of life. Respiration is the mechanism by which energy obtained during the photosynthesis process is transformed into biochemical energy, in the form of ATP. This transformation of energy keeps all cells in all organisms alive. While energy conversion is the main function of respiration in animals, respiration has several other functions in plants. Among them, interactions with photosynthesis such as photorespiration and the production of carbon skeletons for the many compounds synthesized in plants (e.g., pigments, proteins and secondary metabolites). Therefore, it comes as no surprise that such a key role of ...


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