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Assessment Of Hatchery-Reared Pallid Sturgeon Survival In The Lower Missouri River, Kirk D. Steffensen, Larkin A. Powell, Jeff D. Koch 2010 Nebraska Game and Parks Commission

Assessment Of Hatchery-Reared Pallid Sturgeon Survival In The Lower Missouri River, Kirk D. Steffensen, Larkin A. Powell, Jeff D. Koch

Papers in Natural Resources

The population of pallid sturgeon Scaphirhynchus albus in the lower Missouri River between Gavins Point Dam (river kilometer [rkm] 1,305.2) and the confluence with the Mississippi River (rkm 0.0) remains imperiled, little to no natural recruitment occurring. Artificial propagation and subsequent population augmentation (i.e., stocking) may be the only viable option for maintaining pallid sturgeon populations in the lower Missouri River in the near term. Because relatively little is known about the ability of hatchery-reared pallid sturgeon to survive, the objective of this study was to quantify survival estimates for hatchery-reared pallid sturgeon stocked into the ...


To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan 2010 Indiana University Maurer School of Law

To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan

Articles by Maurer Faculty

This article discusses a climbing expedition undertaken by U.S. conservationist George Bird Grinnell to ascend what would come to be known as Grinnell Glacier in Montana. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell’s previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author.


Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah 2010 Walden University

Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah

Walden Dissertations and Doctoral Studies

Hazardous waste site remediation cost estimation requires a good estimate of the contaminated soil volume. The United States Environmental Protection Agency (U.S. EPA) currently uses deterministic point values to estimate soil volumes but the literature suggests that probability bounds analysis (PBA) is the more accurate method to make estimates under uncertainty. The underlying statistical theory is that they are more accurate than deterministic estimates because probabilistic estimates account for data uncertainties. However, the literature does not address the problem of selecting an optimal decision point from the interval-valued PBA estimates. The purpose of this study was to identify the ...


Correlation Of River Terrace Sequences: Widden Brook, Australia, Michael D. Cheetham 2010 Southern Cross University

Correlation Of River Terrace Sequences: Widden Brook, Australia, Michael D. Cheetham

Theses

Terrace sequences can represent regional or continental scale factors such as climatic fluctuations, neotectonic activity and base-level change. However, they can also reflect random incision events brought about by local scale, geomorphic threshold exceedance and subsequent complex response. Through the description and interpretation of the physical landscape and by use of a detailed construction of the chronology, this study explores the formative processes of three discontinuous but adjacent, Late Quaternary step-terrace sequences.

Terrace remnants on Widden Brook, a sandy alluvial stream in southeastern Australia, were examined and correlated longitudinally to establish their evolutionary history. Three distinct, discontinuous terrace sequences, the ...


Social Learning For Resolving Community Conflict Over Land-Use Change To Plantation Forestry, Andrea Jane Leys 2010 Southern Cross University

Social Learning For Resolving Community Conflict Over Land-Use Change To Plantation Forestry, Andrea Jane Leys

Theses

This thesis examines social, economic, political and environmental challenges resulting from the conversion of agricultural land to hardwood forestry plantations for a sub-tropical region of Australia, notably the Upper Clarence catchment in north-eastern NSW. The conversion of agricultural land in the catchment to hardwood forestry plantations was an example of land-use change. This change has implications for natural resource management as a whole, as new operational and management practices impact differently on local ecosystems and communities. One of the aims of this study was to quantify these impacts and examine alternative management scenarios for increasing sustainability outcomes at the landscape ...


Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norm Smith 2010 Boston College

Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norm Smith

Papers in the Earth and Atmospheric Sciences

Using numerical experiments, we investigate how river‐dominated delta channel networks are likely to respond to changes in river discharge predicted to occur over the next century as a result of environmental change. Our results show for a change in discharge up to 60% of the initial value, a decrease results in distributary abandonment in the delta, whereas an increase does not significantly affect the network. However, an increase in discharge beyond a threshold of 60% results in channel creation and an increase in the density of the distributary network. This behavior is predicted by an analysis of an individual ...


Collapse Of The Maya: Could Deforestation Have Contributed?, Robert Oglesby, Thomas L. Sever, William Saturno, David J. Erickson III, Jayanthi Srikishen 2010 University of Nebraska-Lincoln

Collapse Of The Maya: Could Deforestation Have Contributed?, Robert Oglesby, Thomas L. Sever, William Saturno, David J. Erickson Iii, Jayanthi Srikishen

Papers in the Earth and Atmospheric Sciences

The collapse of the Maya civilization during the ninth century A.D. is a major conundrum in the history of mankind. This civilization reached a spectacular peak but then almost completely collapsed in the space of a few decades. While numerous explanations have been put forth to explain this collapse, in recent years, drought has gained favor. This is because water resources were a key for the Maya, especially to ensure their survival during the lengthy dry season that occurs where they lived. Natural drought is a known, recurring feature of this region, as evidenced by observational data, reconstructions of ...


Applying Paleolimnological Techniques To Sub-Tropical East Australian Estuaries, Brendan Logan 2010 Southern Cross University

Applying Paleolimnological Techniques To Sub-Tropical East Australian Estuaries, Brendan Logan

Theses

This thesis examines the application of paleolimnological techniques, pioneered and developed predominately in northern hemisphere freshwater environments, to sub-tropical east Australian estuaries. The aim of this research was to determine how successfully these techniques - in particular those related to coring, dating, diatom analysis and stable isotope analysis – can be either applied or adapted to the estuarine environment to reconstruct nutrient levels in the absence of monitoring data. This will allow pre-impact environmental conditions of estuaries to be determined, which in turn will aid future management decisions.

Fifty-two estuaries from a spatially large geographic area were initially sampled, to create a ...


Conservation Status Of Australian Snubfin Dolphin, Orcaella Heinsohni, And Indo-Pacific Humpback Dolphin, Sousa Chinensis, In The Capricorn Coast, Central Queensland, Australia, Daniele Cagnazzi 2010 Southern Cross University

Conservation Status Of Australian Snubfin Dolphin, Orcaella Heinsohni, And Indo-Pacific Humpback Dolphin, Sousa Chinensis, In The Capricorn Coast, Central Queensland, Australia, Daniele Cagnazzi

Theses

This study examined populations of Australian snubfin dolphins (Orcaella heinsohni) and Indo-Pacific humpback dolphins (Sousa chinensis) inhabiting the coastal waters of the Capricorn Section of the Great Barrier Reef Marine Park, Queensland, Australia. A total of 189 humpback dolphins and 54 snubfin dolphins were identified during 1,760 hours and 20,248 kms of transect surveys completed between 2006 and 2008 in the Capricorn Coast region. Humpback dolphins were found in three different sites: Port Curtis, Keppel Bay and the Northern Region of the study area. In contrast, snubfin dolphins were found only in the Keppel Bay study area. Both ...


Samuel J. Danishetsky And The Synthesis Of Globo-H Antigen, Chelsey Jones 2010 Parkland College

Samuel J. Danishetsky And The Synthesis Of Globo-H Antigen, Chelsey Jones

Natural Sciences Poster Sessions

Samuel J. Danishefsky is a research scientist at the Sloan-Kettering Institute. He uses his knowledge in organic chemistry to make biological advances in cancer research. Danishefsky has been conducting research and experiments on synthesizing anti-cancer vaccines with the use of carbohydrate antigens. Danishefsky has also been conducting research and experiments on homogeneous erythropoietin which could provide insight into how glycoproteins function. Knowledge of glycoprotein would allow scientists to better understand erythropoietin which can treat anemia in chemotherapy patients. All is valuable information in advances in cancer research and cancer research is important because it is a major disease affecting the ...


Building An Oss Quality Estimation Model With Catreg, Athos Origin China, Luiz Fernando Capretz, Danny Ho 2010 University of Western Ontario

Building An Oss Quality Estimation Model With Catreg, Athos Origin China, Luiz Fernando Capretz, Danny Ho

Electrical and Computer Engineering Publications

Open Source Software (OSS) has been a popular form in software development. In this paper, we use statistical approaches to deriveOSSquality estimation models. Our objective is to build estimation models for the number of defects with metrics at project levels. First CATREG (Categorical regression with optimal scaling) is used to obtain quantifications of the qualitative variables. Then the independent variables are validated using the stepwise linear regression. The process is repeated to acquire optimal quantifications and final regression formula. This modeling process is performed based on data from theOSScommunities and is proved to be practically valuable.


Improvement Of Oss Usability: An Empirical Evaluation From Developers Perspective, Luiz Fernando Capretz, Arif Raza, Faheem Ahmed 2010 University of Western Ontario

Improvement Of Oss Usability: An Empirical Evaluation From Developers Perspective, Luiz Fernando Capretz, Arif Raza, Faheem Ahmed

Electrical and Computer Engineering Publications

No abstract provided.


Spatial Analyses Of Pedosphere Carbon Stock And Sequestration Potential In Louisiana's Watersheds, Biao Zhong 2010 Louisiana State University and Agricultural and Mechanical College

Spatial Analyses Of Pedosphere Carbon Stock And Sequestration Potential In Louisiana's Watersheds, Biao Zhong

LSU Doctoral Dissertations

This dissertation research aimed to quantify current soil organic carbon (SOC) stocks across Louisiana’s landscape, examine the spatial relationships between SOC and terrain factors at the watershed and river basin scales, and predict SOC changes in surface soils during future climate change. Using Louisiana as an example, a spatially-explicit modeling framework was developed that is conducive to watershed-scale prediction of soil carbon stock and change. SOC densities at the watershed scale were estimated using the USDA NRCS Soil Geographic Database (STATSGO). Louisiana watersheds and National Land Cover Database (NLCD) were used to aggregate total soil carbon and estimate average ...


Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin 2010 Louisiana State University and Agricultural and Mechanical College

Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin

LSU Doctoral Dissertations

This thesis contains results on two related projects. In the first project, we explore non-axisymmetric instabilities in general relativistic accretion disks around black holes. Such disks are created as transient structures in several astrophysical scenarios, including mergers of compact objects and core collapse of massive stars. These disks are suggested for the role of cenral engines of gamma-ray bursts. We address the stability of these objects against the runaway and non-axisymmetric instabilities in the three-dimensional hydrodynamical fully general relativistic treatment. We explore three slender and moderately slender disk models with varying disk-to-black hole mass ratio. None of the models that ...


Design And Development Of Chiral And Achiral Molecularly Imprinted Stationary Phases, Jason Paul LeJeune 2010 Louisiana State University and Agricultural and Mechanical College

Design And Development Of Chiral And Achiral Molecularly Imprinted Stationary Phases, Jason Paul Lejeune

LSU Doctoral Dissertations

Although the cross-linker can comprise over 80% of the polymer composition, improving the nature of the cross-linker in molecularly imprinted polymers has not been studied extensively. The goal of this research is to develop novel cross-linking monomers to either use in the One MoNomer Molecularly Imprinted Polymer system (OMNiMIP) or use in conjunction with other commercially available cross-linkers and functional monomers. Chapter 2 contains research into the understanding of the performance of a new cross-linking monomer (N, O - bismethacryloyl ethanolamine, NOBE) discovered in the Spivak Research Group. The ability of this monomer to outperform traditional two monomer systems in a ...


Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis 2010 Louisiana State University and Agricultural and Mechanical College

Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis

LSU Doctoral Dissertations

With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands ...


Adsorbate-Enhanced Transport Of Metals On Metal Surfaces: Oxygen And Sulfur On Coinage Metals, Patricia A. Thiel, Mingmin Shen, Da-Jiang Liu, James W. Evans 2010 Iowa State University

Adsorbate-Enhanced Transport Of Metals On Metal Surfaces: Oxygen And Sulfur On Coinage Metals, Patricia A. Thiel, Mingmin Shen, Da-Jiang Liu, James W. Evans

Chemistry Publications

Coarsening (i.e., ripening) of single-atom-high, metal homoepitaxial islands provides a useful window on the mechanism and kinetics of mass transport at metal surfaces. This article focuses on this type of coarsening on the surfaces of coinage metals (Cu, Ag, Au), both clean and with an adsorbed chalcogen (O, S) present. For the clean surfaces, three aspects are summarized: (1) the balance between the two major mechanisms—Ostwald ripening (the most commonly anticipated mechanism) and Smoluchowski ripening—and how that balance depends on island size; (2) the nature of the mass transport agents, which are metal adatoms in almost all ...


Variation Of Growth Morphology With Chemical Composition Of Terraces: Ag On A Twofold Surface Of A Decagonal Al-Cu-Co Quasicrystal, T. Duguet, Barış Ünal, Yong Han, James W. Evans, J. Ledieu, Cynthia J. Jenks, J.-M. Dubois, V. Fournée, Patricia A. Thiel 2010 Institut Jean Lamour

Variation Of Growth Morphology With Chemical Composition Of Terraces: Ag On A Twofold Surface Of A Decagonal Al-Cu-Co Quasicrystal, T. Duguet, Barış Ünal, Yong Han, James W. Evans, J. Ledieu, Cynthia J. Jenks, J.-M. Dubois, V. Fournée, Patricia A. Thiel

Chemistry Publications

Growth of Ag thin films on the twofold surface of a decagonal Al-Cu-Co quasicrystal is characterized by scanning tunneling microscopy, at different temperatures, and for coverages ranging from submonolayer to 11 monolayers. From prior work, three types of clean surface terraces are known to exist. By correlation with a bulk structural model, the major difference between them lies in their transition-metal (TM) content, two being aluminum-rich (0 and 15 at. % TM) and one being TM-rich (40–50 at. % TM). The present article focuses on understanding the difference between Ag film morphologies on these terminations, in terms of their chemical content ...


Formation And Coarsening Of Ag(110) Bilayer Islands On Nial(110): Stm Analysis And Atomistic Lattice-Gas Modeling, Yong Han, Barış Ünal, Dapeng Jing, Feili Qin, Cynthia J. Jenks, Da-Jiang Liu, Patricia A. Thiel, James W. Evans 2010 Iowa State University

Formation And Coarsening Of Ag(110) Bilayer Islands On Nial(110): Stm Analysis And Atomistic Lattice-Gas Modeling, Yong Han, Barış Ünal, Dapeng Jing, Feili Qin, Cynthia J. Jenks, Da-Jiang Liu, Patricia A. Thiel, James W. Evans

Chemistry Publications

Scanning tunneling microscopy analysis of the initial stages of film growth during deposition of Ag on NiAl(110) reveals facile formation of bilayer Ag(110) islands at temperatures of 130 K and above. Annealing subsequent to deposition at 130 K induces coarsening of the bilayer island distribution. The thermodynamic driving force for bilayer island formation reflects a lower relative surface energy for films of even layer thicknesses. This feature derives from quantum size effects due to electron confinement in the Ag film. The kinetics of island formation and relaxation is controlled by terrace and edge-diffusion barriers, detachment barriers, interlayer diffusion ...


Lattice Expansion In Islands Stabilized By Electron Confinement: Ag On Si(111)-7×7, Barış Ünal, Alex Belianinov, Patricia A. Thiel, Michael C. Tringides 2010 Iowa State University

Lattice Expansion In Islands Stabilized By Electron Confinement: Ag On Si(111)-7×7, Barış Ünal, Alex Belianinov, Patricia A. Thiel, Michael C. Tringides

Chemistry Publications

Ag on Si(111)-7×7 was one of the first systems where height selection of metal islands was attributed to electron confinement, i.e., stabilization of selected heights through a quantum size effect (QSE). However, it has been puzzling how the requisite electron standing waves can form, because the Fermi level EF (along the growth [111] direction) is within the gap for bulk Ag. With detailed experiments over a wide coverage and temperature range, we show that a large increase of 12% is present in the interlayer spacing within the bilayer islands. This can shift EF below ...


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