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Focus Catchments : A New Approach To Salinity Research : National Dryland Salinity Program, Steve Porritt Jan 1997

Focus Catchments : A New Approach To Salinity Research : National Dryland Salinity Program, Steve Porritt

Journal of the Department of Agriculture, Western Australia, Series 4

Dry/and salinity is a major threat to the resource base of many rural industries around Australia. More than 1.8 million hectares of once productive land are affected by salinity, with a further 1.6 million hectares at risk in the next 15 to 25 years in Western Australia alone. Much of the past Commonwealth and State expenditure on salinity programs and activities has been poorly targeted and coordinated. In view of this, a national dry/and salinity program that supports specific State salinity management programs has been established jointly between the Commonwealth and State government agencies.

The Upper Kent River Catchment is …


Table Of Contents Volume Eight, Number One, Winter 1997, Risk Editorial Board Jan 1997

Table Of Contents Volume Eight, Number One, Winter 1997, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal RISK: Health, Safety & Environment (ISSN: 1073-8673)


Academy Recommendations On The Proposed Yucca Mountain Waste Repository: Overview And Criticisms, Kristin S. Shrader-Frechette Jan 1997

Academy Recommendations On The Proposed Yucca Mountain Waste Repository: Overview And Criticisms, Kristin S. Shrader-Frechette

RISK: Health, Safety & Environment (1990-2002)

Offers alternative criticism of the NAS report.


Evaluation Of Siting Strategies: The Case Of Two Uk Waste Tire Incinerators, Ragnar E. Lofstedt Jan 1997

Evaluation Of Siting Strategies: The Case Of Two Uk Waste Tire Incinerators, Ragnar E. Lofstedt

RISK: Health, Safety & Environment (1990-2002)

Examines the circumstances that may have contributed to differing outcomes with respect to siting similar facilities in the UK.


Book Review Of Amer Ei-Ahraf & William V. Willis, Management Of Animal Waste - Environmental Health Problems And Technological Solutions, Penny Dean Jan 1997

Book Review Of Amer Ei-Ahraf & William V. Willis, Management Of Animal Waste - Environmental Health Problems And Technological Solutions, Penny Dean

RISK: Health, Safety & Environment (1990-2002)

Review of Amer El-Ahraf & William V. Willis, Management of Animal Waste - Environmental Health Problems and Technological Solutions (Praeger Publishers 1996). About the authors, bibliography, index, introduction, tables. LC 95-654; ISBN 0-275-93529-9 [185 pp. Cloth $65.00. 88 Post Road West, Westport CT 06881.]


Suprachiasmatic Nucleus Neurons Are Glucose Sensitive, Adam C. Hall, Roselle M. Hoffmaster, Edra L. Stern, Mary E. Harrington, David Bickar Jan 1997

Suprachiasmatic Nucleus Neurons Are Glucose Sensitive, Adam C. Hall, Roselle M. Hoffmaster, Edra L. Stern, Mary E. Harrington, David Bickar

Chemistry: Faculty Publications

The suprachiasmatic nucleus (SCN) in the hypothalamus serves as the pacemaker for mammalian circadian rhythms. In a hamster brain slice preparation, the authors were able to record spontaneous activity from SCN cells for up to 4 days in vitro and verify a self-sustained rhythm in firing. The phase of this rhythm was altered by the concentration of glucose in the bathing medium, with time of peak firing advanced for a 20 mM glucose condition and slightly delayed for a 5 mM glucose condition, relative to 10 mM. The advancing effect of 20 mM glucose and the delaying effect of 5 …


Glacial Deposits, Vol. 25, 1996-1997, Department Of Geography-Geology Jan 1997

Glacial Deposits, Vol. 25, 1996-1997, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Response Surface Methodology: An Analytical Method For Locating Migrated Contaminant Sources, Orlando J. Dona Jr. Jan 1997

Response Surface Methodology: An Analytical Method For Locating Migrated Contaminant Sources, Orlando J. Dona Jr.

Theses and Dissertations

The use and storage of hazardous chemicals at U.S. military facilities often adversely affect the groundwater when contaminants infiltrate the subsurface as a result of leaks and accidental spills. These contaminants, if not located and remediated in a relatively short time, may move and settle unpredictably, essentially creating a source some distance from the original leak or spill. An example of this phenomenon is found with migrating dense nonaqueous phase liquid (DNAPL) contaminants. Although various methods for estimating the present day locations of these migrated contaminants are in use, accurately pinpointing the source of contaminants remains a difficult problem in …


The Toysim Project, Anthony Rodriguez Jan 1997

The Toysim Project, Anthony Rodriguez

Theses : Honours

No abstract provided.


Characterization Of Iron Oxides And Atmospheric Corrosion Of Steel, Sei Jin Oh Jan 1997

Characterization Of Iron Oxides And Atmospheric Corrosion Of Steel, Sei Jin Oh

Physics Theses & Dissertations

The study of corrosion behavior was performed using three different analytical techniques, which provided information on the formation, development and layering of iron oxides on the corrosion products as a function of atmospheric conditions, exposure time and type of steel. In particular, the protective layer formed on weathering steel was investigated as a function of different amounts of alloying elements in the steel, atmospheric conditions and exposure times. Combined together, the results provided a better understanding of the atmospheric corrosion behavior of steel, and formed a part of database of the atmospheric corrosion characteristics.

Accurate characterization of the iron oxides …


The Effects Of Human-Computer Communication Mode, Task Complexity, And Desire For Control On Performance And Discourse Organization In An Adaptive Task, Cristina Bubb-Lewis Jan 1997

The Effects Of Human-Computer Communication Mode, Task Complexity, And Desire For Control On Performance And Discourse Organization In An Adaptive Task, Cristina Bubb-Lewis

Psychology Theses & Dissertations

The present study examined how different communication patterns affected task performance with an adaptive interface. A Wizard-of-Oz simulation (Gould, Conti, & Hovanyecz, 1983) was used to create the impression of a talking and listening computer that acted as a teammate to help participants interact with a computer application.

Four levels of communication mode were used which differed in the level of restriction placed on human-computer communication. In addition, participants completed two sets of tasks (simple and complex). Further, a personality trait, Desire for Control (DC), was measured and participants were split into high and low groups for analysis. Dependent measures …


Distribution Of Free Marine Viruses Of Lower Chesapeake Bay And Their Effects On Life-History Parameters Of The Estuarine Copepod Acartia Tonsa Dana, Lisa A. Drake Jan 1997

Distribution Of Free Marine Viruses Of Lower Chesapeake Bay And Their Effects On Life-History Parameters Of The Estuarine Copepod Acartia Tonsa Dana, Lisa A. Drake

OES Theses and Dissertations

Naturally occurring viruses are very abundant in fresh, estuarine, and marine waters, with densities on the order of 105-108 viruses ml-1. Research has focused on virus effects on bacteria, cyanobacteria, and phytoplankton, as well as mechanisms of virus production and decay. However, little is known about the distribution of viruses in benthic environments or virus effects on organisms in higher trophic levels.

To determine the distribution of virus-like particles (VLPs) and bacteria in the lower Chesapeake Bay, vertical profiles of VLPs and bacteria were determined through the water column and 15-25 cm into the sediment …


Journal Of Mathematics And Science: Collaborative Explorations Jan 1997

Journal Of Mathematics And Science: Collaborative Explorations

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Math, Science And Adventures In Space, K. Thornton Jan 1997

Math, Science And Adventures In Space, K. Thornton

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


On The Relationships Between Mathematics And Science In Schools, Z. Usiskin Jan 1997

On The Relationships Between Mathematics And Science In Schools, Z. Usiskin

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Solid-Phase Extraction Method For The Quantitative Analysis Of Organochlorine Pesticides In Wildlife Urine, E. E. Petty, J . J . Johnston, S.A. Volz Jan 1997

Solid-Phase Extraction Method For The Quantitative Analysis Of Organochlorine Pesticides In Wildlife Urine, E. E. Petty, J . J . Johnston, S.A. Volz

United States Department of Agriculture Wildlife Services: Staff Publications

A gas chromatographic method for the analysis of nine organochlorine pesticides in wildlife urine is described. Reversedphase solid-phase extraction is utilized to extract the organochlorine pesticides from urine. The pesticides are recovered by elution with hexane-ethyl ether (1:1) and quantified by gas chromatography with electron-capture detection. Method detection limits range from 1.4 to 2.7 μg/L. Mean recoveries for all pesticides are 90.6%.


Spatial Distribution Of Lead In Soil And Sediment In Iqaluit, Northwest Territories And Links With Human Health, Liisa Ann Peramaki Jan 1997

Spatial Distribution Of Lead In Soil And Sediment In Iqaluit, Northwest Territories And Links With Human Health, Liisa Ann Peramaki

Theses and Dissertations (Comprehensive)

The Baffin Regional Health Board has recently expressed concern over lead poisoning in Iqaluit, NWT, manifested by low haemoglobin levels in children. Several studies in temperate regions have demonstrated links between environmental lead and human health. However, little is known about these links in a permafrost environment. While humans are exposed to lead via a number of different pathways, soils and sediments are two major pathways. The purpose of this study is to determine the spatial distribution of soil and sediment-associated lead in Iqaluit and to assess probable pathways between high lead levels and children. The research hypothesis is that …


Calcium Metabolismn In Volvox Carteri, Bridget Anne Neville Jan 1997

Calcium Metabolismn In Volvox Carteri, Bridget Anne Neville

Honors Theses

Calcium metabolism is involved in many ways in the cellular activities of the colonial green alga, Volvox carteri. Various drugs that are known in other systems to cause specific changes in calcium metabolism, gave rise to various visible metabolic effects in this study. These effects provide evidence for calcium's role in Volvox growth and development and in its cytoskeleton. Another way that calcium exerts its effect on Volvox is by acting as a second messenger in a G-protein/inositol phosphate signal transduction pathway.

This study also supports the fact that cytoskeletal components are important for development in Volvox. Both microtubules and …


A Chemical Extraction Study Of Lead Contaminated Soil From Granite City, Il, Yan Zhang Jan 1997

A Chemical Extraction Study Of Lead Contaminated Soil From Granite City, Il, Yan Zhang

Masters Theses

Granite City, IL, surface soil ( 0-10 cm ) contaminated with lead was studied by both single- and a four-step sequential chemical extraction procedures designed to establish the partitioning, mobility and availability of lead in soil. The five fractions corresponding to the selected extractants were exchangeable, carbonates-bound, Fe-Mn oxides bound, organic matter and residual. Lead contamination of the soil was determined as a function of particle size and soil depth.

The contaminated sample had the highest lead content of 573.1 mg/kg at the 4 cm soil depth level, and on average was about 8.8 times that of background soil. Most …


A Monte Carlo Model Of Uncertainty In A Deterministic Hazardous Waste Transportation Risk Assessment, Michael A. Cowen Jan 1997

A Monte Carlo Model Of Uncertainty In A Deterministic Hazardous Waste Transportation Risk Assessment, Michael A. Cowen

Masters Theses

This thesis is aimed at developing and applying advanced modeling tools in the prediction of risk to the general public from transportation of chemical waste on public highways. The modeling tools developed can then be used to compare alternative waste management scenarios. The application considered is related to the transport of hazardous waste generated by the United States Department of Energy (DOE) to current treatment, storage, and disposal facilities. DOE is currently considering four different scenarios.

The application considered can be more specifically defined as an analysis of the risk to the general public from transporting the 63 shipments of …


Effects Of Perinatal Exposure To Cocaine On Sexually Differentiated Gonadotropin Regulation In Rats, Jihun M. Lee Jan 1997

Effects Of Perinatal Exposure To Cocaine On Sexually Differentiated Gonadotropin Regulation In Rats, Jihun M. Lee

Master's Theses

No abstract provided.


Summing Up: Questions And Answers On The Comprehensive Test Ban Treaty, David W. Hafemeister Jan 1997

Summing Up: Questions And Answers On The Comprehensive Test Ban Treaty, David W. Hafemeister

Physics

My experiences with the ratification of the Strategic Arms Reduction Treaty, the Threshold Test Ban Treaty, and the Conventional Armed Forces in Europe Treaty have led me to conclude that presenting technical issues early in the process greatly reduces their politicization during the ratification end game. This chapter summarizes the important issues that will be raised during the debate on ratification of the Comprehensive Test Ban Treaty. It uses a compact question and answer format to cover the following topics: I. Nuclear Proliferation, II. Nuclear Arms Control, III. Warhead Reliability and Yield for National Security, IV. Warhead Safety, V. Verification, …


Preparation And Reactivity Of Acyclic (Pentadienyl)Iron(1+) Cations: Applications To Organic Synthesis, William A. Donaldson Jan 1997

Preparation And Reactivity Of Acyclic (Pentadienyl)Iron(1+) Cations: Applications To Organic Synthesis, William A. Donaldson

Chemistry Faculty Research and Publications

No abstract provided.


An Assessment Of The Prevalence Of Trichomonas Sp. In The Domestic Pigeon (Columba Livia) Population, In The Emirates Of Abu Dhabi And Dubai, Theresa Caroline Bailey Jan 1997

An Assessment Of The Prevalence Of Trichomonas Sp. In The Domestic Pigeon (Columba Livia) Population, In The Emirates Of Abu Dhabi And Dubai, Theresa Caroline Bailey

Theses

A survey of 250 captive (animal market) and free-flying (trapped at a sheep farm) pigeons was conducted to assess the prevalence of Trichomonas sp. in the domestic pigeon (Columba livia) population, in the United Arab Emirates (UAE). Oropharyngeal swabs demonstrated that 52% of all pigeons were found with Trichomonas sp. in their oropharynx, of which 60%, 68% and 35% of pigeons were Trichomonas sp. positive in the AI Ain and Abu Dhabi animal markets and AI Ain sheep farm respectively. Captive birds had a significantly higher infection rate than the free-flying pigeons. Inspection of the oropharynx of live pigeons positive …


Evaluation Of The Effects Of Afff Inputs On The Vip Biological Nutrient Removal Process And Pass-Through Toxicity. Phase 1a. Volume Ii. Appendix Vii. Acute Toxicity Test Results, Mujde Erten-Unal, Gary C. Schafran Jan 1997

Evaluation Of The Effects Of Afff Inputs On The Vip Biological Nutrient Removal Process And Pass-Through Toxicity. Phase 1a. Volume Ii. Appendix Vii. Acute Toxicity Test Results, Mujde Erten-Unal, Gary C. Schafran

Civil & Environmental Engineering Faculty Publications

This report discusses the results of a bench scale study conducted to evaluate the potential inhibitory effects of untreated AFFF wastewater to the Virginia Initiative Plant VIP biological nutrient removal process. A bench-scale study was conducted to evaluate the potential inhibitory effects of untreated AFFF wastewater to the nitrification process of the Virginia Initiative Plant biological nutrient removal system. Under this testing, bench-scale reactors simulating the nitrification process were loaded at various AFFF concentrations and the influence on the process performance was evaluated. The purpose of this effort was to determine the level of AFFF that could be incorporated into …


Yield-Per-Recruit Analysis And Management Strategies For Atlantic Croaker, Micropogonias Undulatus, In The Middle Atlantic Bight, Luiz R. Barbieri, Mark E. Chittenden, Cynthia M. Jones Jan 1997

Yield-Per-Recruit Analysis And Management Strategies For Atlantic Croaker, Micropogonias Undulatus, In The Middle Atlantic Bight, Luiz R. Barbieri, Mark E. Chittenden, Cynthia M. Jones

OES Faculty Publications

The effect of different fishing mortality (F) and natural mortality (M), and age at first capture (t(c)) on yield-per-recruit of Atlantic croaker, Micropogonias undulatus, in the lower Chesapeake Bay and North Carolina were evaluated with the Beverton-Holt model. Independent of the level of M (0.20-0.35) or F (0.01-2.0) used in simulations, yield-per-recruit values for Chesapeake Bay were consistently higher at t((c)) = 1 and decreased continuously with increases in t(c) (2-5). Although maximum yield-per-recruit always occurred at the maximum level off (F=2.0), marginal increases in yield beyond F = 0.50-0.75 were negligible. Current F (F(CUR)) is estimated to be …


Small Mammals Of Point Pelee National Park: Protecting Biodiversity In Small Reserves (Ontario), Julie Ann Spicer Jan 1997

Small Mammals Of Point Pelee National Park: Protecting Biodiversity In Small Reserves (Ontario), Julie Ann Spicer

Theses and Dissertations (Comprehensive)

Habitat destruction, fragmentation and degradation have been widespread throughout southern Ontario with devastating effects on wetlands. Small reserves are all that in this highly agricultural/urban landscape to protect the biodiversity of Great Lakes Marsh and Carolinian Forest ecosystems. Small reserves are vulnerable to species loss through a host of problems related to size and as a result, the value of small reserves to conservation strategies has often been questioned. Indicator species can be used as a means of studying the conditions of complex ecosystems. In this research, small mammals were sampled in the wetlands of Point Pelee National Park as …


Effect Of Oil Pollution On Juvenile And Adult Rabbitfish (Siganus Canaliculatus), Mohammed Abdul Rahim Hassan Al Zarouni Jan 1997

Effect Of Oil Pollution On Juvenile And Adult Rabbitfish (Siganus Canaliculatus), Mohammed Abdul Rahim Hassan Al Zarouni

Theses

The possible toxic effect of crude oil and dispersant on the reproduction and performance of common marine fish in the United Arab Emirates coasts were investigated. Adult female and juvenile rabbitfish (Siganus canaliculatus) were exposed to different concentration of Sharjah light crude oil (0, 4, 6 ml crude oil/l) in the presence or absence of 0.3 mI/l Nalfleet dispersant (Maxi-Clean 2) dissolved in sea water. Juvenile fish were exposed to treatments for 3, 6, 9 or 15 days and adult female were treated for 18 days. At the end of each experimental period histopathological changes in the skin, gills, liver …


Analysis Of Repeated Measures Data Under Circular Covariance, Andrew Montgomery Hartley Jan 1997

Analysis Of Repeated Measures Data Under Circular Covariance, Andrew Montgomery Hartley

Mathematics & Statistics Theses & Dissertations

Circular covariance is important in modelling phenomena in epidemiological, communications and numerous physical contexts. We introduce and develop a variety of methods which make it a more versatile tool. First, we present two classes of estimators for use in the presence of missing observations. Using simulations, we show that the mean squared errors of the estimators of one of these classes are smaller than those of the Maximum Likelihood (ML) estimators under certain conditions. Next, we propose and discuss a parsimonious, autoregressive type of circular covariance structure which involves only two parameters. We specify ML and other types of estimators …


Coastal Zone Monitoring And Evaluation : A Descriptive Analysis Of Western Australian Practices, Michael F. Williams Jan 1997

Coastal Zone Monitoring And Evaluation : A Descriptive Analysis Of Western Australian Practices, Michael F. Williams

Theses : Honours

Currently there is no information available which documents the monitoring and evaluation practices undertaken in the coastal zone of Western Aust1alia by coastal zone managers. A review of current Australian-wide management practices in coastal management reveals that monitoring and evaluation are limited in their application. The adequacy of the links between coastal monitoring and evaluation, on which our understanding of the state of the coastal zone environment is based, is one of two central themes throughout this research. The other theme is that without an accurate, reliable and effectively managed monitoring and research information base, coastal management will be haphazard …