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A Study Of Fold Characteristics And Deformation Style Using The Evolution Of The Land Surface: Zagros Simply Folded Belt, Iran, Caroline M. Burberry, John W. Cosgrove, Jian-Guo Liu 2010 University of Nebraska-Lincoln

A Study Of Fold Characteristics And Deformation Style Using The Evolution Of The Land Surface: Zagros Simply Folded Belt, Iran, Caroline M. Burberry, John W. Cosgrove, Jian-Guo Liu

Papers in the Earth and Atmospheric Sciences

Deformation styles within a fold-thrust belt can be understood in terms of the spatial organization and geometry of the fold structures. In young fold-thrust belts such as the Zagros, this geometry is reflected topographically by concordant landform morphology. Thus, the distribution of deformation structures can be characterized using satellite image analysis, digital elevation models, the drainage network and geomorphological indicators. The two distinct fold types considered in this study (fault-bend folds and detachment folds) both trending NW-SE, interact with streams flowing NE-SW from the High Zagros Mountains into the Persian Gulf. Multiple abandoned stream channels cross fault-bend folds related to ...


Zebulon Pike: Great American Explorer Or Climate Spy?, Merlin P. Lawson, Randall Cerveny, Cary Mock 2010 University of Nebraska-Lincoln

Zebulon Pike: Great American Explorer Or Climate Spy?, Merlin P. Lawson, Randall Cerveny, Cary Mock

Papers in the Earth and Atmospheric Sciences

Zebulon Pike is known in history books as one of America’s heroes—a great explorer whose adventures in the American West rivaled the Lewis and Clark Expedition and who became the namesake for Colorado’s Pike’s Peak. But what if the history books got it wrong, and Pike was actually not the hero everyone thinks he is? What if he was actually a spy carrying out a secret mission, or a scoundrel interested in overthrowing the American government and helping to carve a new empire out of the North American Southwest? Evidence from Pike’s famed expedition in ...


Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norman D. 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, Norman D. 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 J. 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 J. 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 ...


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 ...


Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky 2010 University of Texas at Austin

Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky

Papers in the Earth and Atmospheric Sciences

Trade‐offs between water‐resource depletion and salinization need to be understood when promoting water‐conservative irrigation practices. This companion paper assesses impacts of groundwater‐fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water‐extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are ...


Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng 2010 University of Nebraska-Lincoln

Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng

Papers in the Earth and Atmospheric Sciences

Effects of the Arctic oscillation (AO) on summer rainfall variability in the central United States are examined in order to improve understanding and prediction of the interannual variation in the summer rainfall. Major results show persistent AO effects that resulted in less summer rainfall in the central United States during the positive phase of the AO and more rainfall during the negative AO phase. These effects are most prominent at the interannual time scale. The key physical processes connecting the AO with the rainfall variations are shown in changes in latitudinal location of the midlatitude upper tropospheric westerly jet over ...


“An Overview Of The Amazonian Aerosol Characterization Experiment 2008 (Amaze-08)” Published In Atmos. Chem. Phys., 10, 11415-11438, 2010, S. T. Martin, M. O. Andreae, D. Althausen, P. Artaxo, H. Baars, S. Borrmann, Q. Chen, D. K. Farmer, A. Guenther, S. S. Gunthe, J. L. Jimenez, T. Karl, K. Longo, A. Manzi, T. Muller, T. Pauliquevis, M. D. Petters, A. J. Prenni, U. Poschl, L. V. Rizzo, J. Schneider, J. N. Smith, E. Swietlicki, J. Tota, A. Wiedensohler, S. R. Zorn 2010 Harvard University

“An Overview Of The Amazonian Aerosol Characterization Experiment 2008 (Amaze-08)” Published In Atmos. Chem. Phys., 10, 11415-11438, 2010, S. T. Martin, M. O. Andreae, D. Althausen, P. Artaxo, H. Baars, S. Borrmann, Q. Chen, D. K. Farmer, A. Guenther, S. S. Gunthe, J. L. Jimenez, T. Karl, K. Longo, A. Manzi, T. Muller, T. Pauliquevis, M. D. Petters, A. J. Prenni, U. Poschl, L. V. Rizzo, J. Schneider, J. N. Smith, E. Swietlicki, J. Tota, A. Wiedensohler, S. R. Zorn

Papers in the Earth and Atmospheric Sciences

No abstract provided.


Multi–Component Nls Models On Symmetric Spaces: Spectral Properties Versus Representations Theory, Vladimir Gerdjikov, Georgi Grahovski 2010 Bulgarian Academy of Sciences

Multi–Component Nls Models On Symmetric Spaces: Spectral Properties Versus Representations Theory, Vladimir Gerdjikov, Georgi Grahovski

Articles

The algebraic structure and the spectral properties of a special class of multicomponent NLS equations, related to the symmetric spaces of BD.I-type are analyzed. The focus of the study is on the spectral theory of the associated Lax operator to these nonlinear evolutionary equations for different fundamental representations of the underlying simple Lie algebra g. Special attention is paid to the spinor representation of the orthogonal Lie algebras of B type.


The Maximal Pure Spectrum Of An Abelian Group, Brendan Goldsmith, Ruediger Goebel 2010 Technological University Dublin

The Maximal Pure Spectrum Of An Abelian Group, Brendan Goldsmith, Ruediger Goebel

Articles

This paper introduces the notion of the maximal pure spectrum of an Abelian group - this is the set of isomorphism classes of maximal proper pure subgroups - and focuses on the situation in which this spectrum is small. The converse situation is also examined i.e. given a collection of isomorphism classes of groups, can one find an Abelian group having precisely this collection as its maximal pure spectrum. Finally, it is shown that in some familiar situations, the answers to these questions may be undecidable.


On The Socles Of Characteristic Subgroups Of Abelian P-Groups, Brendan Goldsmith, Peter Danchev 2010 Technological University Dublin

On The Socles Of Characteristic Subgroups Of Abelian P-Groups, Brendan Goldsmith, Peter Danchev

Articles

Fully invariant subgroups of an Abelian p-group have been the object of a good deal of study, while characteristic subgroups have received somewhat less attention. Recently the socles of fully invariant subgroups have been studied and this led to the notion of a socle-regular group. The present work replaces the fully invariant subgroups with characteristic ones and leads in a natural way to the notion of a strongly socle-regular group. A surprising relationship, mirroring that between transitive and fully transitive groups, is obtained.


From Permutahedron To Associahedron, Colum Watt, Thomas Brady 2010 Technological University Dublin

From Permutahedron To Associahedron, Colum Watt, Thomas Brady

Articles

For each finite real reflection group $W$, we identify a copy of the type-$W$ simplicial generalised associahedron inside the corresponding simplicial permutahedron. This defines a bijection between the facets of the generalised associahedron and the elements of the type-$W$ non-crossing partition lattice which is more tractable than previous such bijections. We show that the simplicial fan determined by this associahedron coincides with the Cambrian fan for $W$.


Climbing Eements In Finite Coxeter Groups, Colum Watt, Thomas Brady, Aisling Kenny 2010 Technological University Dublin

Climbing Eements In Finite Coxeter Groups, Colum Watt, Thomas Brady, Aisling Kenny

Articles

We define the notion of a climbing element in a finite real reflection group relative to a total order on the reflection set and we characterise these elements in the case where the total order arises from a bipartite Coxeter element.


A Model For Predicting Extragalactic Jet Lifetimes, Daniel S. Spicer, Robert Bingham, Stephen O'Sullivan 2010 Drexel University

A Model For Predicting Extragalactic Jet Lifetimes, Daniel S. Spicer, Robert Bingham, Stephen O'Sullivan

Articles

Abstract. In this letter, we propose a model to explain the disintegration of ex- tragalactic jets and to predict the associated timescale. The model assumes that a jet is current and charge neutral as well as collimated at its source; however, the forward electron current gradually decays producing a magnetic field transverse to the direction of jet propagation. This growing transverse magnetic field eventually causes the jet to disintegrate.


Heat Transfer Through The Boundary Layer On A Moving Cylindrical Fibre, Brendan Redmond, David McDonnell 2010 Technological University Dublin

Heat Transfer Through The Boundary Layer On A Moving Cylindrical Fibre, Brendan Redmond, David Mcdonnell

Articles

This paper applies boundary layer theory to the process of manufacturing polymer fibres known as the melt spinning process. The rate of heat loss of the fibre during this process, characterised by the local Nusselt number, is evaluated by means of a Pohlhausen integral method.


Computational Studies Of Stereochemical Effects In The Synthesis Of Sugar Mimics, Louis Anthony Lello 2010 Eastern Michigan University

Computational Studies Of Stereochemical Effects In The Synthesis Of Sugar Mimics, Louis Anthony Lello

Senior Honors Theses & Projects

Density Functional methods are used to model the tandem aza-Cope rearrangement – Mannich cyclization reaction leading to substituted acylpyrrolidines. The ultimate goal is to determine optimum reaction conditions that maximize stereoselectivity, as only one set of stereoisomers is pharmacologically active. Three aspects of the reaction are investigated. First, we determine the relative size of three rotational barriers in the interconversion of two iminium cation stereoisomers that are precursors to the aza-Cope rearrangement. The lowest energy pathway for the interconversion is identified, as well as the relative stability of the two stereoisomers for two different substituents: diphenyl and methyl. Activation barriers are ...


Quantum Mechanical Example Of Anti-Tunneling, Tim Mitchell 2010 University of South Florida

Quantum Mechanical Example Of Anti-Tunneling, Tim Mitchell

Undergraduate Journal of Mathematical Modeling: One + Two

The probability of a particle being reflected by a semi-infinite energy barrier was solved using Schrödinger's equations that describe the quantum mechanical behavior of the particle. The continuity of the functions at the origin allowed the wave functions and their respective derivatives to be equated. Solution of the resulting system yielded values A1 and B1 which were used to calculate the reflection coefficient, (B1/A1)2. The conclusions obtained from these results stated that the particle would be reflected by the barrier when E


A Comparative Analysis Of The Electronic And Structural Characteristics Of Polyphenolic Inhibitos Of Pai-1, Patrick Spoutz 2010 Eastern Michigan University

A Comparative Analysis Of The Electronic And Structural Characteristics Of Polyphenolic Inhibitos Of Pai-1, Patrick Spoutz

Senior Honors Theses & Projects

Polyphenolic compounds containing two gallate groups have been shown to be effective inhibitors of Plasminogen Activator Inhibitor-1 (PAI-1). In this work we use Density Functional calculations to examine energetically-accessible configurations of two digallate compounds exhibiting disparate inhibitory activity toward PAI-1. In addition, we examine the partial charges of potentially acidic protons and the relative stability of the respective conjugate bases of a select group of PAI-1 inhibitors. This analysis was carried out to determine whether such characteristics can be used to distinguish between effective and less effective inhibitors. An examination of the stable configurations of CDE-008 and CDE-056 indicates that ...


Assessing The Feasibility Of An Aerotropolis Around Cleveland Hopkins International Airport, Appendices, Claudette Robey, Daila Shimek, James Wyles, Brian A. Mikelbank, Jim Robey, Kevin O'Brien, et.al. 2010 Cleveland State University

Assessing The Feasibility Of An Aerotropolis Around Cleveland Hopkins International Airport, Appendices, Claudette Robey, Daila Shimek, James Wyles, Brian A. Mikelbank, Jim Robey, Kevin O'Brien, Et.Al.

Urban Publications

This is a companion report to the full technical report entitled, “Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport.” This report contains the supporting documents including interview scripts, focus group protocol, a reference list and glossary, cooperative economic development agreements, airport case studies, a map of physical property characteristics, and endnotes for the appendices.


A K-Mean-Directions Algorithm For Fast Clustering Of Data On The Sphere, Ranjan Maitra, Ivan Peter Ramler 2010 Iowa State University

A K-Mean-Directions Algorithm For Fast Clustering Of Data On The Sphere, Ranjan Maitra, Ivan Peter Ramler

Statistics Publications

A k-means-type algorithm is proposed for efficiently clustering data constrained to lie on the surface of a p-dimensional unit sphere, or data that are mean-zero-unit-variance standardized observations such as those that occur when using Euclidean distance to cluster time series gene expression data using a correlation metric. We also provide methodology to initialize the algorithm and to estimate the number of clusters in the dataset. Results from a detailed series of experiments show excellent performance, even with very large datasets. The methodology is applied to the analysis of the mitotic cell division cycle of budding yeast dataset of ...


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