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2001

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Articles 2881 - 2910 of 3066

Full-Text Articles in Physical Sciences and Mathematics

Abundance, Distribution And Population Characteristics Of Western Grey Kangaroos (Macropus Fuliginosus, Desmarest 1817) In Yellagonga Regional Park, Amy Chang Jan 2001

Abundance, Distribution And Population Characteristics Of Western Grey Kangaroos (Macropus Fuliginosus, Desmarest 1817) In Yellagonga Regional Park, Amy Chang

Theses : Honours

Yellagonga Regional Park is located in the northwest corridor of Perth and constitutes 1400 hectares of wetlands, parkland, open forest and open woodland. Few studies have been conducted on the native fauna in the Park's upland habitats. For this reason, a study of the abundance and distribution of western grey kangaroos (Macropus fuliginosus) was conducted. A walked survey using direct counts and individual recognition of kangaroos during winter, recorded a total of 123 kangaroos, 51 pouch young and 23 unidentified individuals in Yellagonga Regional Park, and a further 24 kangaroos and 18 pouch young at Edith Cowan University's Joondalup campus. …


Exploratory Chemistry In Route To Aromatic Natural Products, Nicholas P. Bizier Jan 2001

Exploratory Chemistry In Route To Aromatic Natural Products, Nicholas P. Bizier

Honors Theses

The focus of this research was the synthesis of two natural products, 1-methyl-s-(1,2,2-trimethy1cyclopentyl)-benzene (formally cuparene), and 3-(1,2dimethylcyclopenty1)-5-methylbenzene-l,2-diol (formally herbertene diol). Cuparene possesses anti-fungal and anti-arthritic properties. This molecule has been the target of a number of syntheses. Herbertene diol, a natural product itself, represents one retrosynthetic step back from mastigophorane; a compound isolated form the liverwort Mastigophora diaclolades. Mastigophorane has been shown to have neural network forming capabilities and has warranted complete synthetic efforts. Through the same chemistry involve in the formation of cuparene, we sought a route to herbertene diol in two steps. We report a successful route to …


Photochemical Degradation Of 2,4-D And Atrazine In Well-Defined Media, Asher D. Ghertner Jan 2001

Photochemical Degradation Of 2,4-D And Atrazine In Well-Defined Media, Asher D. Ghertner

Honors Theses

Atrazine and 2,4-D are common herbicides used for crop, lawn, and rangeland management. Photochemical degradation has been proposed as one safe and efficient remediation strategy for both 2,4-D and Atrazine. In the presence of iron(llI) and hydrogen peroxide these herbicides decay by both thermal and light induced oxidation. Past studies have focused primarily on sun light as an energy source. This work provides a mechanistic description of herbicide degradation incorporating intermediate degradation products produced in the dark and under well-defined light conditions.


Dynamic Update Techniques For Online Maps And Attributes Data, Thanh H. Pham Jan 2001

Dynamic Update Techniques For Online Maps And Attributes Data, Thanh H. Pham

CCE Theses and Dissertations

Online databases containing geographic and related tabular data for maps and attributes often require continuous updates from widely distributed sources afield. For some applications, these data are dynamic, and thus are of little value if they do not reflect the latest information or changes. A status map that depicts graphically temporal data affecting accountability is an example of this type of data. How can accommodations be made collectively for the perpetual data updates in the database and the need to deliver online information in real time without making concessions? The goal of the dissertation was to analyze and evaluate techniques …


Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley Jan 2001

Control Of Phytoplankton Growth By Iron And Silicic Acid Availability In The Subantarctic Ocean: Experimental Results From The Saz Project, D. A. Hutchins, Peter N. Sedwick, G. R. Ditullio, P. W. Boyd, B. Queguiner, F. B. Griffiths, C. Crossley

OES Faculty Publications

Subantarctic Southern Ocean surface waters in the austral summer and autumn are characterized by high concentrations of nitrate and phosphate but low concentrations of dissolved iron (Fe, similar to0.05 nM) and silicic acid (Si, <1 muM). During the Subantarctic Zone AU9706 cruise in March 1998 we investigated the relative importance of Fe and Si in controlling phytoplankton growth and species composition at a station within the subantarctic water mass (46.8degreesS, 142degreesE) using shipboard bottle incubation experiments. Treatments included unamended controls; 1.9 nM added iron (+Fe); 9 muM added silicic acid (+Si); and 1.9 nM addediron plus 9 muM added silicic acid (+Fe+Si). We followed a detailed set of biological and biogeochemical parameters over 8 days. Fe added alone clearly increased community growth rates and nitrate drawdown and altered algal community composition relative to control treatments. Surprisingly, small, lightly silicified pennate diatoms grew when Fe was added either with or without Si, despite the extremely low ambient silicic acid concentrations. Pigment analyses suggest that lightly silicified chrysophytes (type 4 haptophytes) may have preferentially responded to Si added either with or without Fe. However, for many of the parameters measured the +Fe+Si treatments showed large increases relative to both the +Fe and +Si treatments. Our results suggest that iron is the proximate limiting nutrient for chlorophyll production, photosynthetic efficiency, nitrate drawdown, and diatom growth, but that Si also exerts considerable control over algal growth and species composition. Both nutrients together are needed to elicit a maximum growth response, suggesting that both Fe and Si play important roles in structuring the subantarctic phytoplankton community.


Iron In East Antarctic Snow: Implications For Atmospheric Iron Deposition And Algal Production In Antarctic Waters, Ross Edwards, Peter N. Sedwick Jan 2001

Iron In East Antarctic Snow: Implications For Atmospheric Iron Deposition And Algal Production In Antarctic Waters, Ross Edwards, Peter N. Sedwick

OES Faculty Publications

To evaluate the deposition and solubility of aerosol iron in the Antarctic seasonal sea ice zone (SSIZ), iron was measured in snow samples collected from three areas in the SSIZ (Prydz Bay, Dumont d'Urville Sea and Ross Sea) and one continental area (Princess Elizabeth Land) of East Antarctica. Concentrations of total-dissolvable iron (that soluble at pH ~2) ranged from 20-2950 pg g-1, with the lowest concentrations measured in snow from the Dumont d'Urville Sea. Using estimates of snow accumulation rates, we calculate atmospheric iron deposition fluxes of 0.017-0.11 mg m-2 yr-1(0.30-2.0 μmol m-2 yr …


Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson Jan 2001

Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson

OES Faculty Publications

Geochemical records are presented for five sediment cores from basins on the continental shelf of Mac. Robertson Land, East Antarctica. The cores contain 2-4 m thick sequences of hemipelagic, siliceous mud and ooze (SMO) deposited under seasonally open marine conditions. The inner and middle shelf SMO sequences are massive dark olive green material, whereas the outer shelf SMO sequences are dark olive material interspersed with light olive green layers similar to1-10 cm thick. The biogenic material is dominated by marine diatoms including Fragilariopsis curta, Fragilariopsis cylindrus, and Chaetoceros spp. in the dark-colored SMO and Corethron criophilum in the …


The Effect Of Spectral Composition On The Photochemical Production Of Hydrogen Peroxide In Lake Water, Andrea Y. L. Wong, George T. F. Wong Jan 2001

The Effect Of Spectral Composition On The Photochemical Production Of Hydrogen Peroxide In Lake Water, Andrea Y. L. Wong, George T. F. Wong

OES Faculty Publications

Hydrogen peroxide was produced when samples of lake water were exposed to direct or filtered sunlight in which UV or UV(B+C) light was selectively removed. In all cases, the concentration of hydrogen peroxide increased linearly with time-integrated irradiance. While both visible and UV light can induce the formation of hydrogen peroxide, the contribution from the latter was disproportionately large as it was responsible for about two-thirds of the formation of hydrogen peroxide. Among the UV lights, the contributions from UV-A and UV-(B+C) light were 70% and 30% respectively. The contribution from UV-A light was equivalent to about one half of …


Buckets: Smart Objects For Digital Libraries, Michael L. Nelson Jan 2001

Buckets: Smart Objects For Digital Libraries, Michael L. Nelson

Computer Science Faculty Publications

Current discussion of digital libraries (DLs) is often dominated by the merits of the respective storage, search and retrieval functionality of archives, repositories, search engines, search interfaces and database systems. While these technologies are necessary for information management, the information content is more important than the systems used for its storage and retrieval. Digital information should have the same long-term survivability prospects as traditional hardcopy information and should be protected to the extent possible from evolving search engine technologies and vendor vagaries in database management systems. Information content and information retrieval systems should progress on independent paths and make limited …


ข่าวและกิจกรรมสิ่งแวดล้อม Jan 2001

ข่าวและกิจกรรมสิ่งแวดล้อม

Environmental Journal

No abstract provided.


Tackling The Deficit - It Solutions For Art Appreciation - Needs Study And Provision Project At Primary School Level., Séan Ó Hargáin Jan 2001

Tackling The Deficit - It Solutions For Art Appreciation - Needs Study And Provision Project At Primary School Level., Séan Ó Hargáin

Theses

This project looks at the changing environment in terms of the approach to the Visual Arts curriculum at Primary School level. It aims to provide an innovative solution to the art appreciation area, which is being given equal status with the art creation area, which traditionally has been the main focus of the curriculum.

The Project includes a review of the curricular climate, both at home and abroad. In this context it focusses particularly on the role of Information Technology in addressing access problems from those living remote from major population, and therefore major artistic centres.

Primary Research included involved …


An Approach To Networking In Irish Primary Schools, Donal A. O'Connor Jan 2001

An Approach To Networking In Irish Primary Schools, Donal A. O'Connor

Theses

In this Thesis, I hope to develop an approach to networking in the Irish Primary school which will provide practical as well as theoretical advice to Primary Teachers. In the pages that follow, I will detail a general outline of the principles of computer networking and detail models appropriate to the primary school.

At the outset, I wish to acknowledge that there are as many solutions to the primary school’s networking requirements as there are individual schools. This document is intended as a general set of guidelines for the average Primary school in this country. By this, I mean schools …


Development Of Amperometric Enzyme Electrodes For Glucose And Hypoxanthine., Eilish Broderick Jan 2001

Development Of Amperometric Enzyme Electrodes For Glucose And Hypoxanthine., Eilish Broderick

Theses

This thesis is concerned with the immobilisation of enzymes on electrosynthesised poly (o- phenylenediamine) membranes for use on amperometric electrodes. The thesis opens with a discussion of the basic principles of enzymology and a review of a diverse range of biosensors, followed by a consideration of amperometry as governed by the Cottrell equation.

Glucose oxidase and horseradish peroxidase were co-immobilised in poly (o-phenylenediamine) on platinum electrodes at + 0.6 V versus Ag/AgCl. Using this approach the enzymes are entrapped in a strongly adherent, highly reproducible thin membrane, of thickness approximately 10 nm. This one-step procedure produces a glucose sensor with …


Using Computers In The Administration Of Primary Schools, Donncha Ó Fiannachta Jan 2001

Using Computers In The Administration Of Primary Schools, Donncha Ó Fiannachta

Theses

This project investigates the use of computers in the administration of primary schools. A survey has been undertaken to determine current usage and future needs of schools such as training requirements.

It contains an overview of international thinking in this area and looks at aspects such as the legal issues involved in the keeping of electronic data on individuals in schools. Reference is made to the Freedom of Information Act, Data Protection Act and the Education Act.

The author has determined the type of data that is most commonly needed by primary schools in Ireland. Some of this information must …


Development Of A Networked Interactive Information Environment Within A National Park, John Clifton Jan 2001

Development Of A Networked Interactive Information Environment Within A National Park, John Clifton

Theses

For the most part, the Killarney National Park (KNP) currently disseminates information to visitors in paper format and by word of mouth in a non-coherent fashion. Society as a whole is moving towards an Information Age delivered through an electronic medium. This project aims to facilitate the KNP in delivering a new electronically presented information experience to its global visitors.

Electronic media facilitate the delivery of in-depth multimedia as well as multilingual information. This information will be made available on demand to visitors and delivered through a variety of media including information points and handheld devices to facilitate the various …


Development Of Non-Contact Scanning Force Microscopy For Imaging In Liquid Environments, Anthony Grant Jan 2001

Development Of Non-Contact Scanning Force Microscopy For Imaging In Liquid Environments, Anthony Grant

Theses

The aim of this work was to develop a non-contact mode scanning force microscope (SFM) for application to biological samples within liquid environments. Given that biological samples are particularly soft in their natural state and that a liquid is the most difficult operating environment for non-contact mode scanning force microscopy, the development of an instrument that is optimised to image biological samples in vitro presents significant challenges.

Firstly, the SFM tip to sample interaction has to be minimised either, in the worst case, to prevent the sample from being detached from its support or to maximise spatial resolution by minimising …


Design And Implementation Of An Intranet-Solution Especially With Workflow Aspects, Robert Loew Jan 2001

Design And Implementation Of An Intranet-Solution Especially With Workflow Aspects, Robert Loew

Theses

An Intranet support a new or simply an easier information system for all the workers within a company using internet technology. On the one hand, employees can use Web technology and very simple tools to provide and navigate information. On the other hand, the costly and time-consuming business of installing and maintaining software on local PCs can be avoided by using Browser-based Intranet applications. Ideally, it would be possible to access all forms of information processing using one and the same Web browser. This is the aim of the Intranet Project upon which this thesis is based.

Various technologies for …


A Fresh Look At The Provision Of Bandwidth To A Health Agency, James G. Leahy Jan 2001

A Fresh Look At The Provision Of Bandwidth To A Health Agency, James G. Leahy

Theses

This thesis describes development of a networking infrastructure to support a Regional Health Service in Ireland. It covers:-

• The design, building, commissioning and delivery of a Forward Emergency Control Vehicle to provide the video, voice and data communications needed to enhance delivery of patient care in Disaster Situations. The main focus here is on the integration of satellite and terrestrial communications.

• By studying the history of telecommunications provision over copper, the best use is made of the legacy copper cabling in and between existing buildings on a campus to provide both voice and data services.

• A financial …


Verification Of A Distortion In The Microstructure Of Gan Detected By Exafs Using Ab Initio Density Functional Theory Calculations, N. Dimakis, Grant Bunker, M. Katsikini, E. C. Paloura Jan 2001

Verification Of A Distortion In The Microstructure Of Gan Detected By Exafs Using Ab Initio Density Functional Theory Calculations, N. Dimakis, Grant Bunker, M. Katsikini, E. C. Paloura

Physics and Astronomy Faculty Publications and Presentations

X-ray absorption fine structure (XAFS) measurements on a series of epitaxially grown GaN samples have shown a distortion in the microstructure of GaN. More specifically the central N atom is 4-fold coordinated but the four Ga atoms are not equidistant. It has been shown that 2.9 to 3.5 of them (depending on the growth conditions) are found in the expected from XRD distance of 1.94 A and the remaining are at a distance longer by approximately 15%. Second derivative calculation of the conformation energy using the Density Functional Theory (DFT) is used to investigate if the symmetric GaN cluster as …


Cerumen Composition By Flash Pyrolysis-Gas Chromatography/Mass Spectrometry, Craig N. Burkhart, Michael A. Kruge, Craig G. Burkhart, Curtis Black Jan 2001

Cerumen Composition By Flash Pyrolysis-Gas Chromatography/Mass Spectrometry, Craig N. Burkhart, Michael A. Kruge, Craig G. Burkhart, Curtis Black

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Objective: To assess the chemical composition of cerumen by flash pyrolysis-gas chromatography/mass spectrometry.

Study Design: Collected earwax specimens were fractionated into residue and supernatant by means of deoxycholate. This natural bile acid produces significantly better disintegration of earwax in vitro than do presently available ceruminolytic preparations, and also has demonstrated excellent clinical results in vivo to date.

Patients: The sample for analysis was obtained from a patient with clinical earwax impaction.

Results: The supernatant is composed of simple aromatic hydrocarbons, C5-Cl 7 straight-chain hydrocarbons, a complex mixture of compounds tentatively identified as diterpenoids, …


Use Of Py-Gc/Ms Analysis Techniques In Animal Waste Management: A Preliminary Survey Of Dairy Manures, Daniel L. Vaughn, Michael A. Kruge Jan 2001

Use Of Py-Gc/Ms Analysis Techniques In Animal Waste Management: A Preliminary Survey Of Dairy Manures, Daniel L. Vaughn, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The increasing practice of industrial-scale agriculture tends to concentrate large masses of animal waste in relatively compact areas, potentially leading to excessive release of polluting nutrients into waterways during major storms. Anaerobic treatment conditions are generally favored to conserve nitrate N as an agricultural commodity. However, overall N contents in waste are often in excess of crop fertilization needs: storing excess N in soluble nitrate form increases pollution potential. Thus the perceived needs of agriculture and society-at-large become at odds. Organic nitrogen forms (e.g., proteins) are more environmentally stable and are less subject to unintentional release. Although U.S. farmers tend …


Weathering Crust Processes On Melting Glacier Ice (Alberta, Canada), Corinne Joanne Schuster Jan 2001

Weathering Crust Processes On Melting Glacier Ice (Alberta, Canada), Corinne Joanne Schuster

Theses and Dissertations (Comprehensive)

This thesis examines the relationship between the energy balance and hydrology of a glacier at the ice surface interface during the melt season. Experimental sub-catchments were established on the ablation area of the Peyto Glacier, Alberta, Canada, during the summers of 1994, 1995 and 1997. These sub-catchments were equipped with meteorological and hydrological instrumentation to examine relationships in the surface layer. Specifically, the development of a phenomenon known as the weathering crust is followed by examining the ratio between potential surface lowering (calculated from energy available for melt) and actual surface lowering (as measured in the field). This enables an …


Synthesis And Analysis Of Three-Dimensional Molecular Architectures, Patricia Beck Jan 2001

Synthesis And Analysis Of Three-Dimensional Molecular Architectures, Patricia Beck

LSU Master's Theses

The use of resorcinarenes in the study of biologically significant phenomena has been the focus of much attention, due to the versatility of these macrocyclic compounds. In this thesis, two applications of resorcinarenes are explored. First, the search for the mechanism by which tetraarylboronic acid resorcinarenes lead to colorimetric detection and quantization of saccharide analyte concentration in solution is described. Second, the extension of the lower rim conjugation of the resorcinarene macrocycle by the fourfold addition of various length oligo(p-phenylene) rods is discussed. The synthesis of these tubular materials, with potential uses as artificial ion channels and for binding and …


Performance Evaluation Of Hybrid Coding Of Images Using Wavelet Transform And Predictive Coding, S. R. Subramanya, Chaman Sabharwal Jan 2001

Performance Evaluation Of Hybrid Coding Of Images Using Wavelet Transform And Predictive Coding, S. R. Subramanya, Chaman Sabharwal

Computer Science Faculty Research & Creative Works

Image compression techniques are necessary for the storage of huge amounts of digital images using reasonable amounts of space, and for their transmission with limited bandwidth. Several techniques such as predictive coding, transform coding, subband coding, wavelet coding, and vector quantization have been used in image coding. While each technique has some advantages, most practical systems use hybrid techniques which incorporate more than one scheme. They combine the advantages of the individual schemes and enhance the coding effectiveness. This paper proposes and evaluates a hybrid coding scheme for images using wavelet transforms and predictive coding. The performance evaluation is done …


Strictly Positive Definite Functions On A Compact Group, Mohamed Allali, Tomasz Przebinda Jan 2001

Strictly Positive Definite Functions On A Compact Group, Mohamed Allali, Tomasz Przebinda

Mathematics, Physics, and Computer Science Faculty Articles and Research

We recognize a result of Schreiner, concerning strictly positive definite functions on a sphere in an Euclidean space, as a generalization of Bochner's theorem for compact groups.


A Small Look At The Big Picture: Linking Geopotential Height Anomalies To Paleofloods On The Snake River, Idaho And Oregon, Gwendolyn Bernitha Rhodes Jan 2001

A Small Look At The Big Picture: Linking Geopotential Height Anomalies To Paleofloods On The Snake River, Idaho And Oregon, Gwendolyn Bernitha Rhodes

All Master's Theses

A combined paleoflood and flood hydroclimatology study on the Snake River in Idaho and Oregon suggests a link between floods and patters of geopotential height anomalies over the North Pacific Ocean. Examination of the paleoflood record in two 4-m (12 ft) tall terraces along the Hells Canyon reach of the Snake River in Idaho and Oregon shows evidence of at least twenty-two late-Holocene extreme floods that occurred approximately 5,000 years. The ages of paleoflood deposits at these sites fall into two time periods, from 5130 ± 40 to 1960 ± 40 yr BP and from 320 ± 40 yr BP …


Windows Are Key To Keeping Warm In Winter, Donna Falkenborg Jan 2001

Windows Are Key To Keeping Warm In Winter, Donna Falkenborg

All Current Publications

“With the price of fuel skyrocketing, now is the time to think about energy-saving projects around the house, and the best place to start is with your windows,” advises Leona K. Hawks, Utah State University Extension housing specialist.


Renters, Too, Can Save On Utility Costs, Donna Falkenborg Jan 2001

Renters, Too, Can Save On Utility Costs, Donna Falkenborg

All Current Publications

“Most energy conservation information is designed for homeowners, even though an increasing number of people are renting,” says Leona K. Hawks, Utah State University Extension housing specialist. “Many renters develop a short-timer mentality and don’t worry much about energy savings. However, utility bills do add up quickly so renters may wish to conserve on their energy use,” she advises.


What To Do On Your Summer Vacation, Alissa Crans Jan 2001

What To Do On Your Summer Vacation, Alissa Crans

Mathematics Faculty Works

Summer vacation brings back fond memories: playing frisbee in the park, bike-riding till dusk, sipping lemonade on the porch with Grandpa, collecting shells at the beach, solving that difficult math problem you've been working on for the past several weeks. Wait a minute, you say? Many mathematics majors don't realize that numerous summer opportunities exist (many of them paid, so you don't need to get that job bagging groceries, too). A math program provides intellectual stimulation during those hot summer months, bringing your level of concentration up from swatting flies and applying sunscreen. The following descriptions are from actual participants …


The Hadamard Core Of The Totally Nonnegative Matrices, Alissa Crans Jan 2001

The Hadamard Core Of The Totally Nonnegative Matrices, Alissa Crans

Mathematics Faculty Works

An m-by- n matrix A is called totally nonnegative if every minor of A is nonnegative. The Hadamard product of two matrices is simply their entry-wise product. This paper introduces the subclass of totally nonnegative matrices whose Hadamard product with any totally nonnegative matrix is again totally nonnegative. Many properties concerning this class are discussed including: a complete characterization for min{m,n}<4 >; a characterization of the zero–nonzero patterns for which all totally nonnegative matrices lie in this class; and connections to Oppenheim's inequality.