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Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu Apr 2007

Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu

Theses and Dissertations

In chapter 1, we describe development of a mild and efficient method for SNAr iodination of 6-chloropurine 2'-deoxynucleosides and nucleosides. Our studies demonstrate that 6-iodopurine nucleosides are excellent substrates for certain transition metal-catalyzed cross-coupling reactions. In chapter 2, we describe synthesis of protected 6-fluoro, 6-chloro, 6-bromo and 6-sulfonylpurine nucleosides. Comparisons among 6-fluoro-, 6-chloro-, 6-bromo, 6-iodo and 6-sulfonylpurine nucleosides for SNAr reactions with various N, O and S nucleophiles were investigated. Our results demonstrate that the 6-fluoropurine nucleoside is the best substrate for SNAr reactions among the four 6-halopurine nucleosides with oxygen, sulfur and aliphatic amine nucleophiles, and also with an …

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Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia Apr 2007

Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia

Theses and Dissertations

Nanomaterials display interesting physical and chemical properties depending on their shape, size and composition. Self assembly is an intriguing route to producing nanomaterials with controllable compositions and morphologies. DNA has been used to guide the self assembly of materials, resulting in: (1) metal nanowires; (2) metal or semiconductor nanorods; (3) carbon nanotubes; and (4) semiconductor, metal or biological nanoparticles. My work expands the range of DNA templated nanomaterials and develops novel ways of using DNA to pattern nanostructures on surfaces. I have performed the first synthesis of silver nanorods on single stranded DNA, an attractive material for localizing DNA coupled …

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The Effect Of Inquiry-Based Learning In A Technical Classroom: The Impact On Student Learning And Attitude, Ian R. Hartman Apr 2007

The Effect Of Inquiry-Based Learning In A Technical Classroom: The Impact On Student Learning And Attitude, Ian R. Hartman

Theses and Dissertations

This study investigated the effect of inquiry-based instruction in technical undergraduate education. Specifically, the effect was measured along two dimensions: 1) the effect on student learning and, 2) student attitude towards subject matter. The researcher designed an inquiry-based instructional approach to encourage interaction between teacher and students and to help students take more responsibility for their learning. Three technical undergraduate classes participated in the study. Each class was divided into experimental and control groups. For the experimental group, a twice-a-week traditional lecture was replaced with a once-a-week inquiry-based question and answer session. Students in the control group were taught as …

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Investigation Of Novel Microseparation Techniques, Yansheng Liu Apr 2007

Investigation Of Novel Microseparation Techniques, Yansheng Liu

Theses and Dissertations

Ultrahigh pressure liquid chromatography (UHPLC) makes it possible to use very small particles (< 2 µm) as packing materials to provide high column efficiencies. Results from a careful comparison of small porous and nonporous particles show that when the particle size is small enough (< 2 µm), both porous and nonporous particles give excellent performance, and the differences in column efficiencies between porous and nonporous particles become insignificant. Columns packed with bare diamond particles could separate small molecules, especially polar molecules, however, severe tailing occurred for less polar compounds. The polybutadiene coated diamond particles gave greater retention and better separation of small molecules compared to bare particles, although no improvement in column efficiency was observed. Changes in surface bonding of thermally hydrogenated diamond particles was achieved by chemical modification using various organic peroxides with or without reagents containing long carbon chain functional groups. It appears that the alkyl groups were attached onto the diamond surface with limited coverage. LC experiments did not demonstrate good separation; however, changes in LC behavior were observed. A repetitive solvent programming approach was successfully applied to the analysis of a continuous sample stream in microbore LC. Each analysis cycle consisted of three steps: pseudo-injection, elution and rinse. In the pseudo-injection step, elution with a non- or poor-eluting solvent produced a concentrated sample plug due to on-column focusing. Factors influencing peak symmetry, resolution and analysis cycle length were investigated. Quantitative analysis of a continuous sample stream is possible under certain operating conditions. Electric field gradient focusing (EFGF) devices with distributed resistor substrates could focus proteins in the separation channel, however, the focused bands were not stable, and the repeatability was poor due to the formation of bubbles and pH gradient in the separation channel. Both fiber-based and porous glass capillary-based planar EFGF devices with changing cross-sectional area (CCSA) channels were constructed and evaluated with the aid of a home-made scanning laser-induced fluorescence detection system. The fiber-based CCSA EFGF devices gave poorer performance compared with glass capillary based devices. Porous glass capillary-based EFGF devices could focus single proteins and separate mixtures of two to three proteins.

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Hop-By-Hop Transport Control For Multi-Hop Wireless Networks, Daniel N. Scofield Apr 2007

Hop-By-Hop Transport Control For Multi-Hop Wireless Networks, Daniel N. Scofield

Theses and Dissertations

TCP can perform poorly in multi-hop wireless networks due to problems with contention and poor feedback from end-to-end control algorithms. This thesis explores the design of a hop-by-hop transport protocol (HxH). By allowing intermediate nodes to actively participate, the protocol can respond more quickly to changing network conditions and exploit the unique characteristics of wireless networks. Results indicate that hop-by-hop transport can achieve throughput rates that are double those of TCP, depending on the speed of the wireless links.

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Finding Relevant Pdf Medical Journal Articles By The Content Of Their Figures As Well As Their Text, Ammon J. Christiansen Apr 2007

Finding Relevant Pdf Medical Journal Articles By The Content Of Their Figures As Well As Their Text, Ammon J. Christiansen

Theses and Dissertations

This work addresses the need for an alternative to keyword-based search for sifting through large PDF medical journal article document collections for literature review purposes. Despite users' best efforts to form precise and accurate queries, it is often difficult to guess the right keywords to find all the related articles while finding a minimum number of unrelated ones. Failure during literature review to find relevant, related research results in wasted research time and effort in addition to missing significant work in the related area which could affect the quality of the research work being conducted. The purpose of this work …

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T-Spline Simplification, David L. Cardon Apr 2007

T-Spline Simplification, David L. Cardon

Theses and Dissertations

This work focuses on generating approximations of complex T-spline surfaces with similar but less complex T-splines. Two approaches to simplifying T-splines are proposed: a bottom-up approach that iteratively refines an over-simple T-spline to approximate a complex one, and a top-down approach that evaluates existing control points for removal in producing an approximations. This thesis develops and compares the two simplification methods, determining the simplification tasks to which each is best suited. In addition, this thesis documents supporting developments made to T-spline research as simplification was developed.

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Panoramic Video For Efficient Ground Surveillance From Small Unmanned Air Vehicles, Joseph Aaron Jackson Apr 2007

Panoramic Video For Efficient Ground Surveillance From Small Unmanned Air Vehicles, Joseph Aaron Jackson

Theses and Dissertations

As unmanned air vehicle (UAV) utilization increases in Wilderness Search and Rescue (WiSAR) efforts, onboard sensors yielding more information will be desired. UAVs can assist WiSAR efforts by accelerating the ground search process through returning quality aerial footage of the terrain. Additionally, tracking the progress of a search by populating a digital map with video resolution data increases confidence that a comprehensive search of the region has been made. This thesis presents methods for acquiring video from multiple video sensors and fusing them into a single rendered video stream as a Virtual Gimbal. The panoramic video stream is the first …

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Applications Of Search Theory To Coordinated Searching By Unmanned Aerial Vehicles, Steven R. Hansen Apr 2007

Applications Of Search Theory To Coordinated Searching By Unmanned Aerial Vehicles, Steven R. Hansen

Theses and Dissertations

Concepts in optimal search theory have been used in human-based aerial search since World War II. This thesis addresses the technical and theoretical issues necessary to apply this crucial theory to search path planning for Small Unmanned Aerial Vehicles (SUAVs). A typical search often requires that more than one target be located. Accordingly, a method is presented to locate multiple targets in three dimensions, as well as to differentiate between them. However, significant error can be present when locating targets from an airborne platform, and the idea of target quality is also introduced as a way to describe the reliability …

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Hikorocodium Endo Is Not An Alga But An Inozoid Sponge, J. Keith Rigby, Baba Senowbari-Daryan Apr 2007

Hikorocodium Endo Is Not An Alga But An Inozoid Sponge, J. Keith Rigby, Baba Senowbari-Daryan

Faculty Publications

The genus Hikorocodium, with the type species Hikorocodium elegantae from the Permian of Japan, was described originally as a codiacean alga by Endo. It is not a codiacean alga but an inozoid sponge of the family Preperonidellidae. Several fossils described later by Endo and other authors as H. elegantae should be assigned to different inozoid sponge taxa. Specimens of H. fertiliz, described by Endo from the Jurassic of Japan, are also sponge fragments. The taxonomic positions of H. transversum Endo and H. kuramotoi Nakamura, as sponges or

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Improving Microfinance Through Telecommunications, Peter Bladin Apr 2007

Improving Microfinance Through Telecommunications, Peter Bladin

Journal of Microfinance / ESR Review

No abstract provided.

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Pebble In A Pond, Stephen R. Barley Apr 2007

Pebble In A Pond, Stephen R. Barley

Journal of Microfinance / ESR Review

Paul C. Godfrey, associate academic director of BYU’s Economic Self-Reliance Center, sat down with Stephen R. Barley, the Charles M. Pigott Professor of Management Science and Engineering at Stanford University, to discuss problems and needs associated with implementing technology in developing countries. Barley is co-director of the Center for Work, Technology, and Organization at Stanford’s School of Engineering, and the co-director of the Stanford/General Motors Collaborative Research Laboratory. He has written extensively on the impact of new technologies on work, the organization of technical work, and organizational culture. Barley was a member of the Board of Senior Scholars of the …

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Vol. 09 No. 1 Esr Review, Esr Review Apr 2007

Vol. 09 No. 1 Esr Review, Esr Review

Journal of Microfinance / ESR Review

No abstract provided.

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Reading Europe's Paleolithic Writing, Donald Thomas Burgy Apr 2007

Reading Europe's Paleolithic Writing, Donald Thomas Burgy

Comparative Civilizations Review

No abstract provided.

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The Presidential Addresses Of Sir William Jones: The Asiatick Society Of Bengal And The Iscsc, Michael Palencia-Roth Apr 2007

The Presidential Addresses Of Sir William Jones: The Asiatick Society Of Bengal And The Iscsc, Michael Palencia-Roth

Comparative Civilizations Review

No abstract provided.

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Amateur Slaves: An Ethical And Legal Analysis Of The Treatment Of College Athletes, Nathan Curtis Apr 2007

Amateur Slaves: An Ethical And Legal Analysis Of The Treatment Of College Athletes, Nathan Curtis

Brigham Young University Prelaw Review

No abstract provided.

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Full Issue, Review, Prelaw Review Apr 2007

Full Issue, Review, Prelaw Review

Brigham Young University Prelaw Review

No abstract provided.

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Islam In Turkey And Modernization: The Tanzimat Period, Norman C. Rothman Apr 2007

Islam In Turkey And Modernization: The Tanzimat Period, Norman C. Rothman

Comparative Civilizations Review

No abstract provided.

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The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke Mar 2007

The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke

Theses and Dissertations

Phosducin-like protein (PhLP) has been shown to interact with the cytosolic chaperonin containing TCP-1 (CCT), and the βγ subunit dimer of heterotrimeric G proteins (Gβγ). Here we provide details obtained from cryo-electron microscopic and biochemical studies on the structure of the complex between the cytosolic chaperonin CCT and PhLP. Binding of PhLP to CCT occurs through only one of the two chaperonin rings, making multiple contacts with CCT through both its N- and C-terminal domains. In addition, we show that PhLP acts as a co-chaperonin along with CCT in mediating the assembly of the G protein βγ subunit and that …

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Optimizing Product Variant Placement To Satisfy Market Demand, Jonathan Roger Parkinson Mar 2007

Optimizing Product Variant Placement To Satisfy Market Demand, Jonathan Roger Parkinson

Theses and Dissertations

Many companies use product families in order to offer product variants that appeal to different market segments while minimizing costs. Because the market demand is generally not uniform for all possible product variants, during the design phase a decision must be made as to which variants will be offered and how many. This thesis presents a new approach to solving this problem. The product is defined in terms of performance parameters. The market demand is captured in a preference model and applied to these parameters in order to represent the total potential market. The number and placement of the product …

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The Niemann-Pick Type C2 Protein Loads Isoglobotrihexosylceramide Onto Cd1d Molecules And Contributes To The Thymic Selection Of Nkt Cells, Paul B. Savage, Nicolas Schrantz, Yuval Sagiv, Yang Liu, Albert Bendelac, Luc Teyton Mar 2007

The Niemann-Pick Type C2 Protein Loads Isoglobotrihexosylceramide Onto Cd1d Molecules And Contributes To The Thymic Selection Of Nkt Cells, Paul B. Savage, Nicolas Schrantz, Yuval Sagiv, Yang Liu, Albert Bendelac, Luc Teyton

Faculty Publications

The Niemann-Pick type C2 (NPC2) protein is a small, soluble, lysosomal protein important for cholesterol and sphingolipid transport in the lysosome. The immunological phenotype of NPC2-deficient mice was limited to an impaired thymic selection of Valpha 14 natural killer T cells (NKT cells) and a subsequent reduction of NKT cells in the periphery. The remaining NKT cells failed to produce measurable quantities of interferon-gamma in vivo and in vitro after activation with alpha-galactosylceramide. In addition, thymocytes and splenocytes from NPC2-deficient mice were poor presenters of endogenous and exogenous lipids to CD1d-restricted Valpha 14 hybridoma cells. Importantly, we determined that similar …

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Extending The Reach Of Educational Research: Applying Product Commercialization Processes To Communities Of Practice, Richard Edward Culatta Mar 2007

Extending The Reach Of Educational Research: Applying Product Commercialization Processes To Communities Of Practice, Richard Edward Culatta

Theses and Dissertations

The ability to extend educational research beyond the research community could have a great impact on end-users such as teachers, students, or educational administrators. One way to extend the use of educational research is to create tangible educational products; such as virtual simulations, instructional videos, and printed materials; which can be easily and widely distributed. In order to transform research into products, members of the research community must adopt and implement certain product commercialization processes. Effective processes, if not recognized by members of the community, are not helpful for ensuring that quality end products are reached. Likewise, a supportive community …

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On-The-Fly Dynamic Dead Variable Analysis, Joel P. Self Mar 2007

On-The-Fly Dynamic Dead Variable Analysis, Joel P. Self

Theses and Dissertations

State explosion in model checking continues to be the primary obstacle to widespread use of software model checking. The large input ranges of variables used in software is the main cause of state explosion. As software grows in size and complexity the problem only becomes worse. As such, model checking research into data abstraction as a way of mitigating state explosion has become more and more important. Data abstractions aim to reduce the effect of large input ranges. This work focuses on a static program analysis technique called dead variable analysis. The goal of dead variable analysis is to discover …

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Objective Test Methods For Waveguide Audio Synthesis, Steven Gregory Wood Mar 2007

Objective Test Methods For Waveguide Audio Synthesis, Steven Gregory Wood

Theses and Dissertations

Acoustic Physical Modeling has emerged as a newer musical synthesis technique. The most common form of physical modeling synthesis in both industry and academia is digital waveguide synthesis. Commercially available for the past thirteen years, the top synthesizer manufacturers have chosen to include physical modeling synthesis in their top of the line models. In the area of audio quality testing, the most common tests have traditionally been group listening tests. While these tests are subjective and can be expensive and time-consuming, the results are validated by the groups' proper quality standards. Research has been conducted to evaluate objective testing procedures …

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A Multiple-Case Study Of Secondary Reading Specialists, Linda Lucille Frost Mar 2007

A Multiple-Case Study Of Secondary Reading Specialists, Linda Lucille Frost

Theses and Dissertations

This multiple-case study examined the role and educator perceptions of the reading specialist (RS) in the five secondary schools of one school district in the western United States. The purposes of the study were to determine: (1) the actual roles and responsibilities of the secondary RS, (2) whether differences existed in the way RSs, teachers, and principals perceived the role of the RS, and (3) whether the perceptions of the role of the RS were congruent with what the RS actually did. Five RSs, five focus groups comprised of twenty-three teachers, and five principals were interviewed. A survey was also …

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Rectification Of 2-D To 3-D Finite Element Analysis In Buried Concrete Arches Under Discrete Loading, Adam D. Aagard Mar 2007

Rectification Of 2-D To 3-D Finite Element Analysis In Buried Concrete Arches Under Discrete Loading, Adam D. Aagard

Theses and Dissertations

Construction of tunnels and small- to medium-span bridges is a $12 billion per year industry in the United States, with a significant portion going into buried arch structures. Notwithstanding such expenditure, modern arch design and construction, in many cases, is highly conservative. This is because the closed-form solutions used by most designers today do not correctly account for soil-structure interaction. In fact, soil-structure interaction makes a closed form solution impossible. With the advent of high power computers in recent years, some designers have turned to finite element (FE)modeling as the main vehicle of analysis. Such numerical procedures provide an accurate …

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Separate And Joint Analysis Of Longitudinal And Survival Data, Deepthi Rajeev Mar 2007

Separate And Joint Analysis Of Longitudinal And Survival Data, Deepthi Rajeev

Theses and Dissertations

Chemotherapy is a method used to treat cancer but it has a number of side-effects. Research conducted by the Department of Chemical Engineering at BYU involves a new method of administering chemotherapy using ultrasound waves and water-soluble capsules. The goal is to reduce the side-effects by localizing the delivery of the medication. As part of this research, a two-factor experiment was conducted on rats to test if the water-soluble capsules and ultrasound waves by themselves have an effect on tumor growth or patient survival. Our project emphasizes the usage of Bayesian Hierarchical Models and Win-BUGS to jointly model the survival …

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Early Age Assessment Of Cement Treated Materials, Tyler B. Young Mar 2007

Early Age Assessment Of Cement Treated Materials, Tyler B. Young

Theses and Dissertations

In order to avoid the occurrence of early-age damage, cement-treated base (CTB) materials must be allowed to cure for a period of time before the pavement can be opened to traffic. The purpose of this research was to evaluate the utility of the soil stiffness gauge (SSG), heavy Clegg impact soil tester (CIST), portable falling-weight deflectometer (PFWD), dynamic cone penetrometer, and falling-weight deflectometer for assessing early-age strength gain of cement-stabilized materials. Experimentation was performed at four sites on a pavement reconstruction project along Interstate 84 near Morgan, Utah, and three sites along Highway 91 near Richmond, Utah; cement stabilization was …

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The Importance Of The Riemann-Hilbert Problem To Solve A Class Of Optimal Control Problems, Nicholas Dewaal Mar 2007

The Importance Of The Riemann-Hilbert Problem To Solve A Class Of Optimal Control Problems, Nicholas Dewaal

Theses and Dissertations

Optimal control problems can in many cases become complicated and difficult to solve. One particular class of difficult control problems to solve are singular control problems. Standard methods for solving optimal control are discussed showing why those methods are difficult to apply to singular control problems. Then standard methods for solving singular control problems are discussed including why the standard methods can be difficult and often impossible to apply without having to resort to numerical techniques. Finally, an alternative method to solving a class of singular optimal control problems is given for a specific class of problems.

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Fresh Water Ecology Unit For Secondary Education Science Courses, Eric L. Hyer Mar 2007

Fresh Water Ecology Unit For Secondary Education Science Courses, Eric L. Hyer

Theses and Dissertations

Science means “to know", a process for gaining knowledge and an understanding of the natural world. Students need to be involved in active learning. In other words, they must do science, not just hear about it. Good science encourages students to gain knowledge by doing science: observing, questioning, exploring, making and testing hypotheses, comparing predictions, evaluating data, and communicating conclusions. This unit plan is designed to incorporate the components of fresh water, ecology, water quality, and a class-wide science project. Each lesson addresses selected standards from the state core curriculum and has specific objectives that are tied to the learning …

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