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2019

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Articles 751 - 780 of 15927

Full-Text Articles in Physical Sciences and Mathematics

Editorial Board Dec 2019

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


Best Practice Soil Sampling To Depth The Key To Enable Growers To Manage Soil Acidity, Stephen Carr Dec 2019

Best Practice Soil Sampling To Depth The Key To Enable Growers To Manage Soil Acidity, Stephen Carr

The State of Soil Science in WA

Soil acidity affects approximately 50 million hectares of agricultural land in Australia, predominantly in Western Australia (WA) and New South Wales (State of the Environment 2011 committee). Subsurface acidity below 0.1 m, in particular, is a major land degradation issue throughout the WA wheatbelt. Soil acidification is an inevitable consequence of productive agriculture, largely through the addition of acidifying fertilizers, leaching of nitrates and removal of alkaline plant products.


What Lies Deep Beneath – Acid Sulfate Soil Impacts On Groundwater Resources Used For Irrigation, Brad Degens Dec 2019

What Lies Deep Beneath – Acid Sulfate Soil Impacts On Groundwater Resources Used For Irrigation, Brad Degens

The State of Soil Science in WA

Over 17 years have passed since the hazards posed by Acid Sulfate Soils (ASS) were recognised in WA with a catastrophic oxidation event during dewatering of a development in Perth’s northern suburbs. Since then, regional mapping has identified ASS risks lies beneath over 6000 km2 (about half) of the Swan Coastal plain. The risks posed by these soils are mostly to water quality and aquatic ecosystems rather than the directly to soils for agricultural production purposes.


Identification And Classification Of “New” Semi-Arid Soils From The Pilbara Wa With Potential Additions To The Australian Soil Classification, Henry Smolinski, Dennis Van Gool Dec 2019

Identification And Classification Of “New” Semi-Arid Soils From The Pilbara Wa With Potential Additions To The Australian Soil Classification, Henry Smolinski, Dennis Van Gool

The State of Soil Science in WA

As part of the Department of Primary Industries and Regional Development’s (DPIRD) Transforming Agriculture in the Pilbara (TAP) project, a land assessment of the region was conducted to identify areas with potential for irrigated agriculture. The morphology of the dominant soils is described together with their chemical and physical properties.


The All New Australian Soil Classification, Noel R. Schoknecht Dec 2019

The All New Australian Soil Classification, Noel R. Schoknecht

The State of Soil Science in WA

An upgraded 3rd Edition of the ASC will be published in 2020. The most significant change will be the incorporation of a new soil Order - the Arenosols (deep sandy soils) improving its relevance to Western Australian soils. Another planned improvement is providing the classification for free in a number of formats – including the web, a downloadable print-ready pdf and an e-publication – all available on the Soil Science Australia website.


Variable Aluminium Toxicity And Root Distribution In Acidic Soil Profiles, Paul Damon, Gaus Azam, Craig Scanlan, Chris Gazey Dec 2019

Variable Aluminium Toxicity And Root Distribution In Acidic Soil Profiles, Paul Damon, Gaus Azam, Craig Scanlan, Chris Gazey

The State of Soil Science in WA

Subsoil acidity currently affects two thirds of the arable soils in the WA wheatbelt. At acidic soil pH, aluminium (Al) is solubilised from the solid phase into soil solution, creating a direct and localised toxicity to plant roots. Aluminium toxicity to plant roots constrains crop productivity by reducing root proliferation through soil, and inhibiting the capacity of roots to tolerate other constraints, such as compaction. Ongoing acidification of the subsoil is a direct artefact of the productive farming systems that are required to feed our world’s growing appetite for grain and livestock products.


Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde Dec 2019

Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde

Electronic Thesis and Dissertation Repository

Volcanism has played a significant role throughout Mars’ geologic history. Extensive lava flows are widely spread across Mars’ equatorial region, shaping the surface in a very distinct way. In radar images (at the decimeter scale), these flows are bright, which is a typical characteristic of extremely rough, blocky lavas flows seen on Earth. Although the source of the extreme roughness of Martian lava flows is unknown, their surface roughness parameters can be constrained to 1) gain information about Mars’ interior processes, 2) find appropriate analogues on other planetary bodies, and 3) ideally infer the emplacement style of such lavas. Here, …


Influence Of Lime And Crop Rotation On Soil Nitrogen, Dry Matter Production And Microbial Biomass; A Field Trial, Merredin, Wa, Manujla Premaratne, Daniel V. Murphy, Craig Scanlan, Frances C. Hoyle Dec 2019

Influence Of Lime And Crop Rotation On Soil Nitrogen, Dry Matter Production And Microbial Biomass; A Field Trial, Merredin, Wa, Manujla Premaratne, Daniel V. Murphy, Craig Scanlan, Frances C. Hoyle

The State of Soil Science in WA

Nitrogen (N) fertilisers are applied to the soil to meet crop N demands. A large proportion of Western Australian (WA) cropping soils are acidic, decreasing access to plant available nutrients. Application of lime is generally the most effective means of ameliorating increasing soil acidity.


Vacuum Drying Soil Samples Is A Low-Temperature Alternative To Conventional Oven Drying When Determining Soil Water Repellence, Enoch Wong, Philip R. Ward, Matthias Leopold, Daniel V. Murphy, Louise Barton Dec 2019

Vacuum Drying Soil Samples Is A Low-Temperature Alternative To Conventional Oven Drying When Determining Soil Water Repellence, Enoch Wong, Philip R. Ward, Matthias Leopold, Daniel V. Murphy, Louise Barton

The State of Soil Science in WA

Here we investigated a low-temperature (20˚C) soil drying technique to generate soil water contents equivalent to those achieved by conventional oven drying (105˚C). The effect of drying temperature, plus aeration status (oxic or anoxic), on SWR was also investigated.


Soil Exchangeable Cations Increase Microbial Carbon Use Efficiency And Microbial Growth In Acidic Soils, Emilia Horn Dec 2019

Soil Exchangeable Cations Increase Microbial Carbon Use Efficiency And Microbial Growth In Acidic Soils, Emilia Horn

The State of Soil Science in WA

Microbial growth and function is influenced by the properties of the surrounding soil where surface chemistry mediates interactions between individual organisms and their local microenvironment. We hypothesised that the addition of exchangeable base cations, necessary for microbial biochemical function, will increase microbial growth in acidic soils.


Bacterial Processes Associated With Soil C And N Following Application Of Compost And Manure To Dairy Pasture At The Beginning And End Of The Growing Season, Lynette Abbott, Bede Mikan, Zakaria Solaiman, Anjani Weersekara, Sanja Schwab, Ian Waite, Sasha Jenkins Dec 2019

Bacterial Processes Associated With Soil C And N Following Application Of Compost And Manure To Dairy Pasture At The Beginning And End Of The Growing Season, Lynette Abbott, Bede Mikan, Zakaria Solaiman, Anjani Weersekara, Sanja Schwab, Ian Waite, Sasha Jenkins

The State of Soil Science in WA

This study investigated the impact of dairy manure and compost on bacterial community composition and functional diversity in a dairy pasture in south-western Australia.


Improving Aquifer Characterization Through Integration Of Airborne Electromagnetics (Aem) And Well Hydrographs, Jacqueline Polashek Dec 2019

Improving Aquifer Characterization Through Integration Of Airborne Electromagnetics (Aem) And Well Hydrographs, Jacqueline Polashek

School of Natural Resources: Dissertations, Theses, and Student Research

The objective of this study is to evaluate methods of hydrostratigraphic modeling using geophysics and well hydrographs at the eastern edge of the High Plains aquifer (HPA) in Platte and Colfax counties within Nebraska, USA. The HPA is very heterogeneous in the study area, being hosted by architecturally complex glacial sediments and having many irregular hydraulic boundaries. Further, the HPA exhibits local variations between unconfined and confined conditions. Pumping in such bounded aquifers can be unsustainable because of cost increases and lost agricultural productivity. Moreover, the large drawdowns typical of confined aquifers can contribute to well interference during heavy pumping. …


The Firece Green Fire: Vol. 10 Issue 12, Wofford College Environmental Studies Program Dec 2019

The Firece Green Fire: Vol. 10 Issue 12, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


A Risk Analysis Of Microplastic Consumption In Filter Feeders, Sheri Rahman Dec 2019

A Risk Analysis Of Microplastic Consumption In Filter Feeders, Sheri Rahman

HCNSO Student Capstones

Microplastics (plastic particles < 5 mm) pose a serious threat to marine organisms, as researchers have documented such particles in the gut contents of numerous species. In particular, filter feeders are at risk of consuming microplastics because they may accidentally consume the particulates when feeding or they may prey on species that have already consumed them. The goals of this research were to evaluate the risks that different filter feeders face in regards to microplastic consumption through the analysis of the calculated Microplastic Consumption Rates for numerous species of filter feeders. Factors that could potentially affect this risk were also considered, including ocean basin, environment type, salinity, life stage, IUCN status, and filtration technique. Initial analysis showed that body size greatly impacted a species’ risk of microplastic consumption and further tests were completed to evaluate overall microplastic contamination for each species. Microplastic consumption and microplastic contamination values were evaluated and analyzed to determine which filter feeding species were most at risk of experiencing ecological effects from microplastic pollution. From a resource management perspective, this research highlights the filter feeding species most at risk, contributing to the development of more effective plastic waste management policies.


Arctic Thaw: Environmental Exploitation For Economic Profit, Stephen F. Moulton Dec 2019

Arctic Thaw: Environmental Exploitation For Economic Profit, Stephen F. Moulton

HCNSO Student Capstones

“Arctic Thaw: Environmental Exploitation for Economic Profit,” is a comprehensive, interdisciplinary assessment of Arctic climate change (CC) impacts. Arctic CC alters the regions’ temperature, annual ice cover, and sea levels. This alteration influences the global economy through enriched international trade and fossil hydrocarbon extraction developments. This capstone examines the Arctic’s response to CC through economic statistical analysis, tracking relative sea-level (RSL) trends, as well as performing hydrographic and modeling reviews. The Northern Rim Countries (NRCs) economic analysis assesses potential CC and GSLR impacts by applying statistical techniques to calculate its effect on each country’s gross domestic product (GDP). The tidal …


Spatial And Temporal Trends Of Southeastern Florida's Octocoral Comunity, Alexandra Hiley Dec 2019

Spatial And Temporal Trends Of Southeastern Florida's Octocoral Comunity, Alexandra Hiley

HCNSO Student Theses and Dissertations

In the Caribbean, local and global stressors have driven significant declines in scleractinian coral cover up to 80% in only three decades. Following these declines, phase shifts in benthic community composition have been reported. Shifts towards macroalgal dominance has been the most widely observed case, however, shifts towards octocoral and sponge dominance have also been reported. In Florida, USA, the Florida Reef Tract is an extensive barrier reef system that contains diverse assemblages of corals, sponges, fish, and other taxa. The Southeast Florida Reef Tract (SEFRT) within the Southeast Florida Coral Reef Conservation Area is the northern portion of this …


Pesticide Seed Treatments Containing Neonicotinoids Have Limited Effect On Soil Microbial Community Structure Under Different Tillage Regimes, Jessica E. Mackay, Richard G. Smith, Jessica G. Ernakovich, Lukas T. Bernhardt Dec 2019

Pesticide Seed Treatments Containing Neonicotinoids Have Limited Effect On Soil Microbial Community Structure Under Different Tillage Regimes, Jessica E. Mackay, Richard G. Smith, Jessica G. Ernakovich, Lukas T. Bernhardt

Faculty Publications

Pesticide seed treatments (PST) which contain fungicides and insecticides are commonly used in agriculture; however, little is known about their effect on soil microbial communities and soil health. Neonicotinoids – controversial insecticides which are common in PST – have received criticism due to potential non-target effects. While fungal pathogens need to be moderated, PST have the potential to disturb broader fungal communities which could lead to reduced nutrient cycling and poor soil health. Given the broad use of PST, their effect on soil fungi needs to be studied within the context of other agricultural management practices. For example, tillage regimes …


Dronescape:Distributed Rapid On-Site Network Self-Deploying Cellular Advanced Phone Environment, Daryl Johnson, Bill Stackpole Dec 2019

Dronescape:Distributed Rapid On-Site Network Self-Deploying Cellular Advanced Phone Environment, Daryl Johnson, Bill Stackpole

Presentations and other scholarship

When disasters happen, the speed with which first responders and emergency personnel can contact and be contacted by the people affected by the disaster during the first minutes or hours is critical. Early communications can make the difference between life and death. During a disaster communications infrastructure of the affected area is likely to be compromised. This project proposes an inexpensive, rapidly deployable cloud of autonomous drones, each coupled with a micro-cellular base station that deploys from a transportable deployment module. The goal is to temporarily restore communications for both first responders to communicate amongst themselves as well as for …


Relaxation Of Radiation Effects In Polymers, Alexandra Hughlett Nelson Dec 2019

Relaxation Of Radiation Effects In Polymers, Alexandra Hughlett Nelson

Physics Capstone Projects

Radiation can create atomic-scale defect states in polymers, leading to changes in their optical, electrical and mechanical properties. Recent studies of polymers have shown that these defect states are sensitive to oxygen or water exposure. It is believed that oxygen cause the number of defect states to decrease and the polymers to revert to their original states. However, the time scale of this regression is not known. This experiment quantified the time that it takes five polymers to recover and the extent of said recovery; polypropylene (PP), low density polyethylene (LDPE), fluorinated ethylene propylene (FEP), polymide (PI), and poly ether …


Search For B− → Λp⊽ ⊽ With The Babar Experiment, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al. Dec 2019

Search For B− → Λp⊽ ⊽ With The Babar Experiment, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al.

Faculty Publications

A search for the rare flavor-changing neutral current process B− → Λp̅ νv̅ using data from the BABAR experiment has been performed. A total of 424 fb−1 of e+e collision data collected at the center-of-mass energy of the ϒ(4S) resonance is used in this study, corresponding to a sample of (471 ± 3) × 106 BB̅ pairs. Signal B− → Λp̅ νv̅ candidates are identified by first fully reconstructing a B+ decay in one of many possible exclusive decays to hadronic final states, then examining detector activity that is not associated with …


Life In Hampton Roads Survey No. 4: Neighborhood Flooding And Insurance, News @ Odu Dec 2019

Life In Hampton Roads Survey No. 4: Neighborhood Flooding And Insurance, News @ Odu

News Items

No abstract provided.


A Desire Fulfillment Theory Of Digital Game Enjoyment, Owen M. Schaffer Dec 2019

A Desire Fulfillment Theory Of Digital Game Enjoyment, Owen M. Schaffer

College of Computing and Digital Media Dissertations

Empirical research on what makes digital games enjoyable is critical for practitioners who want to design for enjoyment, including for Game Design, Gamification, and Serious Games. But existing theories of what leads to digital game enjoyment have been incomplete or lacking in empirical support showing their impact on enjoyment.

Desire Fulfillment Theory is proposed as a new theory of what leads to digital game enjoyment and tested through research with people who have recently played a digital game. This theory builds on three established theories: Expectancy Disconfirmation Theory, Theory of Basic Human Desires, and Flow Theory. These three theories are …


Semitransparent Sb2s3 Thin Film Solar Cells By Ultrasonic Spray Pyrolysis For Use In Solar Windows, Jako S. Eensalu, Atanas Katerski, Erki Kärber, Lothar Weinhardt, Monika Blum, Clemens Heske, Wanli Yang, Ilona Oja Acik, Malle Krunks Dec 2019

Semitransparent Sb2s3 Thin Film Solar Cells By Ultrasonic Spray Pyrolysis For Use In Solar Windows, Jako S. Eensalu, Atanas Katerski, Erki Kärber, Lothar Weinhardt, Monika Blum, Clemens Heske, Wanli Yang, Ilona Oja Acik, Malle Krunks

Chemistry and Biochemistry Faculty Research

The integration of photovoltaic (PV) solar energy in zero-energy buildings requires durable and efficient solar windows composed of lightweight and semitransparent thin film solar cells. Inorganic materials with a high optical absorption coefficient, such as Sb2S3 (>105 cm−1 at 450 nm), offer semitransparency, appreciable efficiency, and long-term durability at low cost. Oxide-free throughout the Sb2S3 layer thickness, as confirmed by combined studies of energy dispersive X-ray spectroscopy and synchrotron soft X-ray emission spectroscopy, semitransparent Sb2S3 thin films can be rapidly grown in air by the area-scalable ultrasonic spray pyrolysis method. Integrated into a ITO/TiO2/Sb2S3/P3HT/Au solar cell, a power conversion …


Inclusion Of Kinetic Proteomics In Multi-Omics Methods To Analyze Calorie Restriction Effects On Aging, Richard Hajime Carson Dec 2019

Inclusion Of Kinetic Proteomics In Multi-Omics Methods To Analyze Calorie Restriction Effects On Aging, Richard Hajime Carson

Theses and Dissertations

One of the greatest risk factors for disease is advanced age. As the human lifespan has increased, so too have the burdens of caring for an increasingly older population suffering from rising rates of cardiovascular disease, kidney disease, diabetes, and dementia. The need for improving medical technology and developing new therapies for age-related diseases is manifest. Yet our understanding of the processes of aging and how to attenuate the effects of aging remains incomplete. Various studies have established calorie restriction as a robust method for extending lifespan in laboratory organisms; however the mechanism is a topic of much debate. Advancing …


Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith Dec 2019

Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith

Biology ETDs

The fundamental currency of life is energy. Organisms need energy to grow, to survive and to reproduce. Understanding the acquisition of energy by consumers is thus a foundational aspect of biological research. This is especially important in the modern era, as impacts of ongoing anthropogenic effects will be mediated or amplified through food webs. Here, I explore how isotopic analysis of individual amino acids – a technique new to ecological studies – can be used to trace energy flow through animal communities in modern and ancient time periods. In particular, I focus on kelp forest food webs, which are nearshore …


Translating Soils Information Into Better Land Planning Decisions: An Example From The Peel-Harvey Catchment Western Australia, Heather M. Percy, Andrew Del Marco, Tom Lerner, Brett Flugge Dec 2019

Translating Soils Information Into Better Land Planning Decisions: An Example From The Peel-Harvey Catchment Western Australia, Heather M. Percy, Andrew Del Marco, Tom Lerner, Brett Flugge

The State of Soil Science in WA

State planning policy for the Peel-Harvey coastal plain catchment requires decision makers to consider land suitability when assessing proposals for intensive agriculture including for horticulture. This information is not accessible or easily understood by land use planners. We will describe how we translated this information into a model Local Planning Policy (LPP) for the Peel-Harvey.


Validating And Extending The National Better Fertiliser Decisions For Pasture Critical Values For Phosphorus, David Rogers, David Weaver, Ron Master, Robert Summers Dec 2019

Validating And Extending The National Better Fertiliser Decisions For Pasture Critical Values For Phosphorus, David Rogers, David Weaver, Ron Master, Robert Summers

The State of Soil Science in WA

Viable pasture based grazing systems in south-western Australia have been made possible over much of the landscape through input of nutrients to soils which were impoverished when first cleared. Initial dramatic increases in production stimulated subsequent applications of fertilisers, particularly phosphatic fertilisers, ever since. However, excessive fertiliser application can be tied to environmental impacts including the loss of phosphorus (P) to waterways impacting on water quality.


Electrochemical Investigation Into The External Failure Modes Of Oil And Gas Pipelines, Maxwell Goldman Dec 2019

Electrochemical Investigation Into The External Failure Modes Of Oil And Gas Pipelines, Maxwell Goldman

Electronic Thesis and Dissertation Repository

Carbon steel is the material of choice for transmission pipelines for the oil and gas industry across the globe due to its mechanical properties, and low cost. Carbon steel is only resistffxidant, and the types of anions present in the exposure environment. Transmission pipelines are coated with non-conductive polymeric coatings and can be protected by cathodic protection in order to mitigate exterior corrosion. The primary goals of this thesis were to determine the role of anions, cathodic charging with hydrogen, and steel microstructure on different failure modes of carbon steel.

The corrosion mechanism of carbon steel in the presence of …


Legacy Phosphorus – Have We Fallen Asleep At The Wheel?, Simon Clarendon, David Weaver, Robert Summers Dec 2019

Legacy Phosphorus – Have We Fallen Asleep At The Wheel?, Simon Clarendon, David Weaver, Robert Summers

The State of Soil Science in WA

Reducing nutrient loss from agricultural landscapes using management practices in Australia has long been advocated to improve water quality. Water quality, i.e. phosphorus (P) concentrations are commonly used to measure the effectiveness of management practices at the paddock level. However, the effectiveness of paddock scale management practices is often not reflected at a catchment scale, in part due to levels of implementation, but also due to the equilibrium effects of legacy P.


Rapid Soil Analytical Techniques For International Agricultural Research And Development, Wendy Vance, Mike Tf Wong, Anthony Ringrose-Voase, Soil And Water Science Office, Cambodian Agricultural Research And Development Institute, Department Of Agricultural Research, Myanmar Dec 2019

Rapid Soil Analytical Techniques For International Agricultural Research And Development, Wendy Vance, Mike Tf Wong, Anthony Ringrose-Voase, Soil And Water Science Office, Cambodian Agricultural Research And Development Institute, Department Of Agricultural Research, Myanmar

The State of Soil Science in WA

Soil analysis is used to assess natural resources and inform management to improve long-term farming profitability. Conventional techniques typically use different methods, equipment, reagents and skills to measure each soil property of interest. The consequence is that a conventional soil laboratory is expensive to set up, maintain and run. These issues result in many countries (and organisations) having to do without a well-functioning conventional soil laboratory. Developments in spectroscopic and potentiometric methods of soil analysis means that these countries need not go without reliable soil analysis.