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Dark Solitons In Cigar-Shaped Bose-Einstein Condensates In Double-Well Potentials, S Middelkamp, G Theocharis, PG Kevrekidis, DJ Frantzeskakis, P Schmelcher 2010 University of Massachusetts - Amherst

Dark Solitons In Cigar-Shaped Bose-Einstein Condensates In Double-Well Potentials, S Middelkamp, G Theocharis, Pg Kevrekidis, Dj Frantzeskakis, P Schmelcher

Mathematics and Statistics Department Faculty Publication Series

We study the statics and dynamics of dark solitons in a cigar-shaped Bose-Einstein condensate confined in a double-well potential. Using a mean-field model with a noncubic nonlinearity, appropriate to describe the dimensionality crossover regime from one- to three-dimensional, we obtain branches of solutions in the form of single and multiple dark soliton states, and study their bifurcations and stability. It is demonstrated that there exist dark soliton states which do not have a linear counterpart and we highlight the role of anomalous modes in the excitation spectra. Particularly, we show that anomalous mode eigenfrequencies are closely connected to the characteristic ...


Use Of The Cmaq And Wrf-Chem Models To Investigate Tropospheric Ozone And Particulate Matter In The El Paso-Juarez Airshed, Juan Gustavo Arias Ugarte 2010 University of Texas at El Paso

Use Of The Cmaq And Wrf-Chem Models To Investigate Tropospheric Ozone And Particulate Matter In The El Paso-Juarez Airshed, Juan Gustavo Arias Ugarte

Open Access Theses & Dissertations

Ground level ozone pollution is a continuing environmental concern in several U.S cities. A necessary step towards understanding and quantifying the problem is the implementation of numerical models that can predict pollutant concentrations. Simulations were performed using the Community Multiscale Air Quality (CMAQ) and the (Weather Research Forecast/Chemical (WRF-Chem) models to study the tropospheric ozone and particulate matter concentrations in the El Paso-Juarez Airshed and to analyze the influence of U.S and Mexican cities as possible contributors to ground level ozone pollution in this region. This study involves the implementation and validation of both the CMAQ and ...


Simulation And Optimization Of Ultra Thin Photovoltaics, Jose Luis Cruz-Campa 2010 University of Texas at El Paso

Simulation And Optimization Of Ultra Thin Photovoltaics, Jose Luis Cruz-Campa

Open Access Theses & Dissertations

Sandia National Laboratories (SNL) conducts pioneering research and development in Micro-Electro-Mechanical Systems (MEMS) and solar cell research. This dissertation project combines these two areas to create ultra-thin small-form-factor crystalline silicon (c-Si) solar cells. These miniature solar cells create a new class of photovoltaics with potentially novel applications and benefits such as dramatic reductions in cost, weight and material usage.

At the beginning of the project, unusually low efficiencies were obtained in the research group. The intention of this research was thus to investigate the main causes of the low efficiencies through simulation, design, fabrication, and characterization.

Commercial simulation tools were ...


Tectonic Geomorphology Of The Puna Tsang Chhu, Western Bhutan, Abby May Woody 2010 University of Texas at El Paso

Tectonic Geomorphology Of The Puna Tsang Chhu, Western Bhutan, Abby May Woody

Open Access Theses & Dissertations

There are two boundaries, or physiographic transitions, between three distinct topographic regions in Bhutan. The southern and northern regions have relatively steep hillslopes and high relief, while the central region has gentle hillslopes and low relief. The geomorphology of a 70-km stretch along the Puna Tsang Chhu valley between the towns of Uma and Amrimo was studied in March and April of 2009 to provide constraints on the active tectonics of western Bhutan and the nature of these physiographic transitions.

The Puna Tsang Chhu valley contains a set of alluvial cut-and-fill and bedrock (strath) river terraces with associated sediments - younger ...


Designing Payments For Ecosystem Services, James Salzman 2010 Duke Law School

Designing Payments For Ecosystem Services, James Salzman

Faculty Scholarship

This Policy Series by James Salzman brings attention to a rapidly developing phenomenon—payments for ecosystem services (PES).

Salzman, the Samuel F. Mordecai Professor of Law and the Nicholas Institute Professor of Environmental Policy at Duke University, explains when and where ecosystem services can be provided by voluntary markets rather than government actions. The key to understanding how PES work is rooted in the basis of any voluntary market transaction—gains from trade. One party agrees to take action because another party offers an incentive. Both parties benefit. A beekeeper, for example, brings her hives to an orchard to provide ...


Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori 2010 University of Texas at El Paso

Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori

Open Access Theses & Dissertations

Water pollution is major environmental problem worldwide. Many common industrial organic compounds that make their way into water systems can be carcinogenic at trace levels and are difficult and costly to remove completely with conventional technologies. Because of this, authorities and researchers are trying to improve current water cleanup techniques.

Heterogeneous photocatalysts that accelerate the photocatalytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Titanium dioxide has the potential to completely mineralize organic compounds in water under ultraviolet light ...


Physical And Biochemical Assessment Of Mexican Palo Verde Response To Chromium Toxicity, Yong Zhao 2010 University of Texas at El Paso

Physical And Biochemical Assessment Of Mexican Palo Verde Response To Chromium Toxicity, Yong Zhao

Open Access Theses & Dissertations

In the United States, about 1/3 of the 1400 superfund sites have been reported to be chromium contaminated, making chromium the second most common metal found in superfund chemical contamination sites. Chromium removal from soil has commonly been carried out via chemical, physical, and thermal processes. However, these methods are expensive and/or invasive to local ecosystems. In contrast to these techniques, phytoremediation (the use of plants to remove toxic substances from areas containing contamination at low or medium levels) appears to be a cost-effective and environmentally friendly process for chromium removal. However, most reports on chromium phytoremediation suggest ...


Bayesian Nonparametric Regression With A Flexible Error Term Distribution, Courtney Marie Barnes 2010 University of Texas at El Paso

Bayesian Nonparametric Regression With A Flexible Error Term Distribution, Courtney Marie Barnes

Open Access Theses & Dissertations

Datasets often exhibit heavy tailed behavior and standard analyses are often heavily influenced by outliers. We propose a nonparametric regression model whose error term distribution is a mixture of a normal and a Student t distribution. This results in a model that is more resistant to outliers compared to a model with a normal error term.


Synthesis And Manufacture Of Photocrosslinkable Poly(Caprolactone)-Based 3d Scaffolds For Tissue Engineering Applications, Nathan Jonathan Castro 2010 University of Texas at El Paso

Synthesis And Manufacture Of Photocrosslinkable Poly(Caprolactone)-Based 3d Scaffolds For Tissue Engineering Applications, Nathan Jonathan Castro

Open Access Theses & Dissertations

It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however, generally cause more trouble since the body is incapable of repairing them. Bone defects can occur as a result of congenital abnormalities, trauma, or disease. Traditional methods for addressing these defects have involved the use of acellular cadaverous bone or autologous bone. Both contain innate problems associated with them; the former method can result in disease transmission, as well as very low integration with the host ...


A New Photochemical Method For The Preparation Of Amino Acid-α-Phenylthioesters And Peptide-α-Phenylthioesters, Tyrone Hogenauer 2010 University of Texas at El Paso

A New Photochemical Method For The Preparation Of Amino Acid-α-Phenylthioesters And Peptide-α-Phenylthioesters, Tyrone Hogenauer

Open Access Theses & Dissertations

We describe the development of a novel resin with a photoreactive N-acylnitroindoline linker that allows for the synthesis of amino acid- (in solution) or peptide-α-thioesters using standard Fmoc/t-Bu standard solid phase peptide synthesis (SPPS). Recent advances have shown that the yields of this thioesterification reaction have dramatically increased due to a simple change in the order of addition of reagents. Upon illumination with UV-light, in the presence of N-hydroxybenzotriazole (HOBt), the amino acid- or peptide-α-OBt ester is generated by direct photo-release from the nitroindoline linker with minimal epimerization, followed by reaction with thiophenol in the dark to produce amino ...


Symmetry And Stability Of Homogeneous Flocks, J. J. P. Veerman 2010 Portland State University

Symmetry And Stability Of Homogeneous Flocks, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

The study of the movement of flocks, whether biological or technological, is motivated by the desire to understand the capability of coherent motion of a large number of agents that only receive very limited information. In a biological flock a large group of animals seek their course while moving in a more or less fixed formation. It seems reasonable that the immediate course is determined by leaders at the boundary of the flock. The others follow: what is their algorithm? The most popular technological application consists of cars on a one-lane road. The light turns green and the lead car ...


Ecological And Evolutionary Connectivity Of Reef Corals In Subtropical Eastern Australia : Implications For The Persistence Of High-Latitude Coral Populations, Annika ME Noreen 2010 Southern Cross University

Ecological And Evolutionary Connectivity Of Reef Corals In Subtropical Eastern Australia : Implications For The Persistence Of High-Latitude Coral Populations, Annika Me Noreen

Theses

Coral reefs worldwide are threatened by a variety of pressures, and climate change models predict increasing levels of chronic stress as well as acute disturbances for most reefs. In addition to these global threats, populations on remote reefs are also predicted to be vulnerable due to their isolation from potential source reefs, usually low population size and associated increased extinction risk. Critical for the future of these reefs is dispersal and gene flow between populations (connectivity). This study investigated connectivity, population subdivision, and genetic diversity for three scleractinian reef coral species in discontinuous high-latitude nearshore coral communities and offshore reefs ...


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 ...


Developing Preservice Teachers’ Mathematical And Pedagogical Knowledge Using An Integrated Approach, Leigh A. Van den Kieboom, Marta Magiera 2010 Marquette University

Developing Preservice Teachers’ Mathematical And Pedagogical Knowledge Using An Integrated Approach, Leigh A. Van Den Kieboom, Marta Magiera

Mathematics, Statistics and Computer Science Faculty Research and Publications

This paper describes how an integrated mathematics content and early field-experience course provides opportunities for preservice elementary teachers to develop understanding of mathematics and mathematics teaching. Engaging preservice teachers in solving and discussing mathematical tasks and providing opportunities to implement these tasks with elementary students creates an authentic context for the future teachers to reflect on their own understanding of mathematics, mathematics teaching, and students’ mathematical thinking. Essential elements of the cycle of events in the integrated model of instruction are discussed: preservice students’ acquisition of mathematical concepts in the context of selected tasks in the content course; subsequent posing ...


Coaching: One Mathematics Specialist's Story, C. B. Doyle 2010 Richmond Public Schools

Coaching: One Mathematics Specialist's Story, C. B. Doyle

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Providing Real-World Experiences: The Virginia Tech Externship For Mathematics Specialists, B. Kreye, J. L. M. Wilkins 2010 Virginia Polytechnic Institute & State University

Providing Real-World Experiences: The Virginia Tech Externship For Mathematics Specialists, B. Kreye, J. L. M. Wilkins

Journal of Mathematics and Science: Collaborative Explorations

We describe the structure and implementation of the yearlong Externship experience associated with the Mathematics Specialist program at Virginia Polytechnic Institute & State University (Virginia Tech). We discuss the assignments and experiences included in the Externship, the alignment of those experiences with the job description developed by the Virginia Mathematics and Science Coalition Task Force, and teacher comments on the effectiveness of their Externship experiences [1].


Mathematics Professional Development Workshop For Middle School Teachers: Concept Versus Memorization, D. Taylor, R. W. Farley 2010 Virginia Commonwealth University

Mathematics Professional Development Workshop For Middle School Teachers: Concept Versus Memorization, D. Taylor, R. W. Farley

Journal of Mathematics and Science: Collaborative Explorations

This article includes professional development topics for middle school mathematics and science teachers from two week-long Urban Teacher Institutes. These Institutes were held at J. Sargeant Reynolds Community College (JSRCC) and its partner institution, Virginia Commonwealth University (VCU), during the summers of 2007 and 2008, and were supported by a grant obtained by Dr. Harriet Morrison (JSRCC). Co-author Dr. Dewey Taylor directed the 2007 workshop, and both authors served as faculty leaders in both workshops. The workshops focused on teaching in an urban environment and "community mapping" (understanding the details of a certain locale to make the teacher more knowledgeable ...


Understanding The Transition Between High School And College Mathematics And Science, S. A. Culpepper, C. Basile, C. A. Ferguson, J. A. Lanning, M. A. Perkins 2010 University of Colorado Denver

Understanding The Transition Between High School And College Mathematics And Science, S. A. Culpepper, C. Basile, C. A. Ferguson, J. A. Lanning, M. A. Perkins

Journal of Mathematics and Science: Collaborative Explorations

Mathematics and science education is gaining increasing recognition as key for the well-being of individuals and society. Accordingly, the transition from high school to college is particularly important to ensure that students are prepared for college mathematics and science. The goal of this study was to understand how high school mathematics and science course-taking related to performance in college. Specifically, the study employed a nonparametric regression method to examine the relationship between high school mathematics and science courses, and academic performance in college mathematics and science courses. The results provide some evidence pertaining to the positive benefits from high school ...


Reflections On What You Have Learned: A Rapporteur's Report On Virginia's "What We Have Learned Symposium", D. B. Erchick 2010 The Ohio State University at Newark

Reflections On What You Have Learned: A Rapporteur's Report On Virginia's "What We Have Learned Symposium", D. B. Erchick

Journal of Mathematics and Science: Collaborative Explorations

In this Rapporteur's Report on Virginia's "What We Have Learned Symposium" about a statewide Mathematics Specialist program, I discuss emergent topics resulting from presentations and discussion at the Symposium. Topics include defining Mathematics Specialists and coaches, addressing mathematics content in the program, providing ongoing support for Specialists and coaches, and supporting principals. I also provide suggestions, discuss absences in the program, and comment on cautions in revision and needs in dissemination.


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