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Full-Text Articles in Physical Sciences and Mathematics

Design And Synthesis Of Cationic Steroid Antimicrobial Compounds, Synthesis Of Glycolipids Recognized By Natural Killer T Cells And Development Of Tlr-1, Tlr-6 Heterodimer Binders And Studies Of Their Immunology Activities, Yanshu Feng Dec 2011

Design And Synthesis Of Cationic Steroid Antimicrobial Compounds, Synthesis Of Glycolipids Recognized By Natural Killer T Cells And Development Of Tlr-1, Tlr-6 Heterodimer Binders And Studies Of Their Immunology Activities, Yanshu Feng

Theses and Dissertations

Cationic steroid antimicrobial agents (CSAs) are a family of bile acid derivatives. These compounds are amphiphilic and mimic endogenous antimicrobial peptides. The antimicrobial activities of CSA-13 have been investigated and due to portent bactericidal activities and low toxicity, a large amount of CSA-13 is demanded for clinic trails and other antimicrobial applications. During our studies, we optimized the synthetic route of CSA-13, so that it can be prepared at the kilogram, even in tons scale. We investigated three routes and one of them is suitable for industry, because only recrystallization is needed in the synthesis. Natural killer T cells (NKT …


Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi Dec 2011

Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi

Theses and Dissertations

This thesis focuses on using mass spectrometry-based techniques for characterizing the structure and behavior of cucurbituril complexes in the gas phase. Both solvent and counter ion effects can be completely eliminated in the gas phase and the intrinsic interactions in the system are directly shown in the experimental results. Chapter 1 introduces the structures, properties and host-guest chemistry of cucurbituril, and FTICR mass spectrometry including instrumentation, performance and working principles. Two mass spectrometry-based methods for supramolecular characterization, sustained off-resonance irradiation collision induced dissociation (SORI CID) and ion molecule equilibrium measurements, are also discussed in this chapter. Chapter 2 characterizes the …


Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai Dec 2011

Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai

Theses and Dissertations

G-protein coupled receptor signaling (GPCR) is essential for regulating a large variety of hormonal, sensory and neuronal processes in eukaryotic cells. Because the regulation of these physiological responses is critical, GPCR signaling pathways are carefully controlled at different levels within the cascade. Phosducin-like protein 1 (PhLP1) can bind the G protein βγ dimer and participate in GPCR signaling. Recent evidence has supported the concept that PhLP1 can serve as a co-chaperone of the eukaryotic cytosolic chaperonin complex CCT/TRiC to mediate G βγ assembly. Although a general mechanism of PhLP1-mediated G βγ assembly has been postulated, many of the details about …


A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith Dec 2011

A General Model For Continuous Noninvasive Pulmonary Artery Pressure Estimation, Robert Anthony Smith

Theses and Dissertations

Elevated pulmonary artery pressure (PAP) is a significant healthcare risk. Continuous monitoring for patients with elevated PAP is crucial for effective treatment, yet the most accurate method is invasive and expensive, and cannot be performed repeatedly. Noninvasive methods exist but are inaccurate, expensive, and cannot be used for continuous monitoring. We present a machine learning model based on heart sounds that estimates pulmonary artery pressure with enough accuracy to exclude an invasive diagnostic operation, allowing for consistent monitoring of heart condition in suspect patients without the cost and risk of invasive monitoring. We conduct a greedy search through 38 possible …


Development Of A Strontium-87 Ion Interferometer, Christopher Joseph Erickson Dec 2011

Development Of A Strontium-87 Ion Interferometer, Christopher Joseph Erickson

Theses and Dissertations

I present the construction of a low-velocity intense source (LVIS) of laser-cooled neutral strontium using permanent ring magnets. The LVIS consists of a magneto-optical trap from which cold strontium is extracted in a well-collimated beam. I also present the development and implementation of a full suite of low-noise, high-bandwidth laser control electronics including a microcontroller unit. This microcontroller remotely controls and monitors the current driver, temperature controller, and PID lock circuit for each diode laser simultaneously. The current driver output is accurate to within 2 micro-amps and repeatable to with a few nano-amps. The noise spectral density of the current …


Framework To Secure Cloud-Based Medical Image Storage And Management System Communications, Timothy James Rostrom Dec 2011

Framework To Secure Cloud-Based Medical Image Storage And Management System Communications, Timothy James Rostrom

Theses and Dissertations

Picture Archiving and Communication Systems (PACS) have been traditionally constrained to the premises of the healthcare provider. This has limited the availability of these systems in many parts of the world and mandated major costs in infrastructure for those who employ them. Public cloud services could be a solution that eases the cost of ownership and provides greater flexibility for PACS implementations. This could make it possible to bring medical imaging services to places where it was previously unavailable and reduce the costs associated with these services for those who utilize them. Moving these systems to public cloud infrastructure requires …


An Integrated Geophysical And Geologic Study Of The Paleogene-Age Volcanic Body And Possible Landslide Deposit On The South Slope Of The Traverse Mountains, Utah, John C. Hoopes Dec 2011

An Integrated Geophysical And Geologic Study Of The Paleogene-Age Volcanic Body And Possible Landslide Deposit On The South Slope Of The Traverse Mountains, Utah, John C. Hoopes

Theses and Dissertations

Development of homes, roads, and commercial buildings in northern Utah has grown significantly during the last several decades. Construction has expanded from the valley floor to higher elevations of benches, foothills, and other elevated regions of the Wasatch Mountain Front. Construction in the higher elevation areas are a concern due to potential for landslides, both new and reactivated. Landslides have been identified in this region and are dated as Pleistocene to historical in age. A possible landslide of about 0.5 km2 on the south slope of Traverse Mountain has been mapped by the Utah Geological Survey in 2005. Its surface …


Screening Designs That Minimize Model Dependence, Kenneth P. Fairchild Dec 2011

Screening Designs That Minimize Model Dependence, Kenneth P. Fairchild

Theses and Dissertations

When approaching a new research problem, we often use screening designs to determine which factors are worth exploring in more detail. Before exploring a problem, we don't know which factors are important. When examining a large number of factors, it is likely that only a handful are significant and that even fewer two-factor interactions will be significant. If there are important interactions, it is likely that they are connected with the handful of significant main effects. Since we don't know beforehand which factors are significant, we want to choose a design that gives us the highest probability a priori of …


Quality Selection For Dynamic Adaptive Streaming Over Http With Scalable Video Coding, Travis L. Andelin Dec 2011

Quality Selection For Dynamic Adaptive Streaming Over Http With Scalable Video Coding, Travis L. Andelin

Theses and Dissertations

Video streaming on the Internet is increasingly using Dynamic Adaptive Streaming over HTTP (DASH), in which the video is converted into various quality levels and divided into two-second segments. A client can then adjust its video quality over time by choosing to download the appropriate quality level for a given segment using standard HTTP. Scalable Video Coding (SVC) is a promising enhancement to the DASH protocol. With SVC, segments are divided into subset bitstream blocks. At playback, blocks received for a given segment are combined to additively increase the current quality. Unlike traditional DASH, which downloads segments serially, this encoding …


Quantification Of Glacier Melt Volume In The Indus River Watershed, Maria Nicole Asay Dec 2011

Quantification Of Glacier Melt Volume In The Indus River Watershed, Maria Nicole Asay

Theses and Dissertations

Quantifying the contribution of glaciers to water resources is particularly important in locations where glaciers may provide a large percentage of total river discharge. In some remote locations, direct field measurements of melt rates are difficult to acquire, so alternate approaches are needed. Positive degree-day modeling (PDD) of glacier melt is a valuable tool to making first order approximations of the volume of melt coming from glaciers. In this study, a PDD-melt model is applied to glaciers in the Indus River watershed located in Afghanistan, China, India, and Pakistan. Here, millions of people rely on the water from the Indus …


Dynamic Appointment Scheduling In Healthcare, Mckay N. Heasley Dec 2011

Dynamic Appointment Scheduling In Healthcare, Mckay N. Heasley

Theses and Dissertations

In recent years, healthcare management has become fertile ground for the scheduling theory community. In addition to an extensive academic literature on this subject, there has also been a proliferation of healthcare scheduling software companies in the marketplace. Typical scheduling systems use rule-based analytics that give schedulers advisory information from programmable heuristics such as the Bailey-Welch rule cite{B,BW}, which recommends overbooking early in the day to fill-in potential no-shows later on. We propose a dynamic programming problem formulation to the scheduling problem that maximizes revenue. We formulate the problem and discuss the effectiveness of 3 different algorithms that solve the …


A Search For And Characterization Of Young Stellar Objects In N206, An H Ii Complex In The Large Magellanic Cloud, Tabitha Christi Buehler Dec 2011

A Search For And Characterization Of Young Stellar Objects In N206, An H Ii Complex In The Large Magellanic Cloud, Tabitha Christi Buehler

Theses and Dissertations

I have identified 51 young stellar object candidates in N206, an H II complex in the nearby Large Magellanic Cloud galaxy. Using archival images from the Spitzer Space Telescope, supplemented with other infrared and optical images, I located point sources in this region. I distinguished possible young stellar objects based on their spectral energy distributions, morphologies, and locations in color-magnitude space. I classified the young stellar object candidates based on their likelihood of being young stellar objects and based on their apparent evolutionary stages. The spatial distribution of these candidates in N206 indicates that star formation is being triggered …


Electron Screening And Disorder-Induced Heating In Ultracold Neutral Plasmas, Mary Elizabeth Lyon Dec 2011

Electron Screening And Disorder-Induced Heating In Ultracold Neutral Plasmas, Mary Elizabeth Lyon

Theses and Dissertations

Disorder-induced heating (DIH) is a nonequilibrium, ultrafast relaxation process that occurs when laser-cooled atoms are photoionized to make an ultracold plasma. Its effects dominate the ion motion during the first 100 ns of the plasma evolution. Using tools of atomic physics we study DIH with ns time resolution for different plasma densities and temperatures. By changing the frequency of the laser beam we use to probe the ions, we map out the time evolution of the velocity distribution. We can compare this to a fluorescence simulation in order to more clearly determine the relationship between the fluorescence signal and the …


Fast Spheroidal Weathering With Colluvium Deposition, Mckay T. Farley Nov 2011

Fast Spheroidal Weathering With Colluvium Deposition, Mckay T. Farley

Theses and Dissertations

It can be difficult to quickly and easily create realistic sandstone terrain. Film makers often need to generate realistic terrain for establishing the setting of their film. Many methods have been created which address terrain generation. One such method is using heightmaps which encode height as a gray-value in a 2d image. Most terrain generation techniques don't admit concavities such as overhangs and arches. We present an algorithm that operates on a voxel grid for creating 3d terrain. Our algorithm uses curvature estimation to weather away the terrain. We speed up our method using a caching mechanism that stores the …


Carry And Expand: A New Nomadic Interaction Paradigm, Richard B. Arthur Nov 2011

Carry And Expand: A New Nomadic Interaction Paradigm, Richard B. Arthur

Theses and Dissertations

People are nomadic; traveling from place to place. As a user travels, he may need access to his digital information, including his data, applications, and settings. A convenient way to supply this access is to have the user carry that digital information in a portable computer such as a laptop or smart phone. As Moore's Law continues to operate, devices such as smart phones can easily perform the computing necessary for a user's work. Unfortunately, the amount of data a human can receive and convey through such devices is limited. To receive more information humans require more screen real estate. …


A Foveated System For Wilderness Search And Rescue In Manned Aircraft, Carson D. Fenimore Nov 2011

A Foveated System For Wilderness Search And Rescue In Manned Aircraft, Carson D. Fenimore

Theses and Dissertations

Wilderness search and rescue can be assisted by video searchers in manned aircraft. The video searcher's primary task is to find clues on the ground. Due to altitude, it may be difficult to resolve details on the ground with a standard video camera. As the video streams at a constant frame rate, the searcher may become distracted by other tasks. While handling these tasks the searcher may miss important clues or spend extra time flying over the search area; either outcome decreases both the effectiveness of the video searcher and the chances of successfully finding missing persons. We develop an …


Modeling And Designing Fair Rate Control For Wireless Mesh Networks With Partial Interference, Lei Wang Nov 2011

Modeling And Designing Fair Rate Control For Wireless Mesh Networks With Partial Interference, Lei Wang

Theses and Dissertations

Internet rate control protocols, such as TCP, encounter severe performance problems in wireless mesh networks. Because wireless networks use shared communication channels, contention and interference can significantly degrade flow throughput and fairness. Existing research takes either an engineering-based or optimization-based approach to solve the performance problems. The engineering-based approach usually solves a specific observed problem, but does not necessarily optimize the overall performance. The optimization-based approach mathematically models the network to find the optimal resource allocation among competing flows. The model can lead to a distributed rate control algorithm with performance guarantees, but relatively little work has been done to …


Topological Properties Of Invariant Sets For Anosov Maps With Holes, Skyler C. Simmons Nov 2011

Topological Properties Of Invariant Sets For Anosov Maps With Holes, Skyler C. Simmons

Theses and Dissertations

We begin by studying various topological properties of invariant sets of hyperbolic toral automorphisms in the linear case. Results related to cardinality, local maximality, entropy, and dimension are presented. Where possible, we extend the results to the case of hyperbolic toral automorphisms in higher dimensions, and further to general Anosov maps.


Sequence Stratigraphy Of Basal Oquirrh Group Caronates (Bashkirian) Thorpe Hills, Lake Mountain, Wasatch Front, Utah, Andrew D. Derenthal Nov 2011

Sequence Stratigraphy Of Basal Oquirrh Group Caronates (Bashkirian) Thorpe Hills, Lake Mountain, Wasatch Front, Utah, Andrew D. Derenthal

Theses and Dissertations

The Early Pennsylvanian (Bashkirian/Morrowan) Bridal Veil Limestone of north-central Utah was deposited in the eastern portion of the rapidly subsiding Oquirrh basin. The 420 meter-thick Bridal Veil Limestone displays distinct cyclicity formed by stacked, meter to decameter scale high-frequency sequences and their constituent parasequences. Though no one ideal cycle may be defined for the Bridal Veil Limestone, each high-frequency sequence and parasequence contains a general shallowing upward trend that ranges from anaerobic to dysaerobic mudstone at the base to skeletal wackestone to mud-dominated packstone, capped by heterozoan grain-rich carbonates or siliciclastic tidalites. Cycles bounded by exposure surfaces, indicated by micro-brecciation, …


Fabrication And Application Of Vertically Aligned Carbon Nanotube Templated Silicon Nanomaterials, Jun Song Oct 2011

Fabrication And Application Of Vertically Aligned Carbon Nanotube Templated Silicon Nanomaterials, Jun Song

Theses and Dissertations

A process, called carbon nanotube templated microfabrication (CNT-M) makes high aspect ratio microstructures out of a wide variety of materials by growing patterned vertically aligned carbon nanotubes (VACNTs) as a framework and then infiltrating various materials into the frameworks by chemical vapor deposition (CVD). By using the CNT-M procedure, a partial Si infiltration of carbon nanotube frameworks results in porous three dimensional microscale shapes consisting of silicon-carbon nanotube composites. The addition of thin silicon shells to the vertically aligned CNTs (VACNTs) enables the fabrication of robust silicon nanostructures with edibility to design a wide range of geometries. Nanoscale dimensions are …


Improving Multi-Label Classification By Avoiding Implicit Negativity With Incomplete Data, Derrall L. Heath Oct 2011

Improving Multi-Label Classification By Avoiding Implicit Negativity With Incomplete Data, Derrall L. Heath

Theses and Dissertations

Many real world problems require multi-label classification, in which each training instance is associated with a set of labels. There are many existing learning algorithms for multi-label classification; however, these algorithms assume implicit negativity, where missing labels in the training data are automatically assumed to be negative. Additionally, many of the existing algorithms do not handle incremental learning in which new labels could be encountered later in the learning process. A novel multi-label adaptation of the backpropagation algorithm is proposed that does not assume implicit negativity. In addition, this algorithm can, using a naive Bayesian approach, infer missing labels in …


Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang Oct 2011

Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang

Theses and Dissertations

Total Synthesis of 4'-ester Resveratrol Analogs and 8, 9-amido Geldanamycin Analog and toward the Total Synthesis of (-)-Englerin A Yong Wang Department of Chemistry and Biochemistry, BYU Doctor of Philosophy The phytoalexin resveratrol and its 4'-ester analogs have been prepared with a decarbonylative Heck reaction. The deprotecting step has been modified and improved to increase yield and avoid chromatography. A set of resveratrol analogs and resveratrol have been tested with melanoma and pancreatic cell assays. The 8, 9-amido Geldanamycin analog has been synthesized with a convergent route, involving 28 simplified steps in its longest linear sequence. Synthetic methodologies, such as …


Follicular Dendritic Cells, Resting Cd4+ T Cells And Human Immunodeficiency Virus Expression, Changna Wang Sep 2011

Follicular Dendritic Cells, Resting Cd4+ T Cells And Human Immunodeficiency Virus Expression, Changna Wang

Theses and Dissertations

Many events associated with Human Immunodeficiency Virus (HIV) infection/replication occur in and around the germinal centers (GCs) of secondary lymphoid tissues where follicular dendritic cells (FDCs) reside, suggesting that this microenvironment may contribute unique signaling that is important to viral progression. My research focused on characterizing signaling, both positive and negative, contributed by FDCs that affects HIV infection and replication. Specifically, I determined if FDC signals could induce the expression of latent HIV in T cells and if so, to characterize the signaling pathways involved. Moreover, I also examined the ability of FDCs to produce inhibitory signals that might block …


Implications Of Dune Pattern Analysis For Titan's Surface History, Christopher Jon Savage Aug 2011

Implications Of Dune Pattern Analysis For Titan's Surface History, Christopher Jon Savage

Theses and Dissertations

Analyzing dune parameters such as dune width and spacing can be useful in determining the reaction of dunes to changes in atmospheric and sedimentary conditions currently and in the recent geologic past. Dune parameters, dune width and spacing, were measured for linear dunes in regions across Saturn's moon Titan from images T21, 23, 28, 44 and 48 collected by Synthetic Aperture RADAR aboard the Cassini spacecraft in order to reconstruct the surface history of Titan. Dunes in the five study swaths are all linear in form, but lack superimposed or flanking dunes. They have a mean width of 1.3 km …


Aryl Acetate Phase Transfer Catalysis: Method And Computation Studies, Meisha A. Binkley Aug 2011

Aryl Acetate Phase Transfer Catalysis: Method And Computation Studies, Meisha A. Binkley

Theses and Dissertations

Brief explanation and history of cinchona based Phase Transfer Catalysis (PTC). Studied aryl acetates in PTC, encompassing napthoyl, 6-methoxy napthoyl, phenyl and protected 4-hydroxy phenyl acetates. Investigated means of controlling the selectivity of the PTC reaction by changing the electrophile size, the ether side group size or by addition of inorganic salts. Found that either small or aromatic electophiles increased enantioselectivity more than aliphatic electrophiles, and that increasing the size of ether protecting group also increased selectivity. Positive effects of salt addition included either decreasing reaction time or increasing enantiomeric excess. Applied findings towards the synthesis of S-equol. Computational experiments …


On The Measurement Of Angular Dependent Sound Transmission Through Airborne Supercritical Plates, Matthew D. Shaw Aug 2011

On The Measurement Of Angular Dependent Sound Transmission Through Airborne Supercritical Plates, Matthew D. Shaw

Theses and Dissertations

A method of measuring angular dependence of acoustic transmission through supercritical plates in air is discussed. The coincidence effect occurs in a supercritical plate when the component of the acoustic wave number parallel to the plate matches the bending wave number in the plate. The transmission of sound is a maximum at the angle where this trace wave number matching occurs. The theory of the coincidence effect is well-defined for unbounded thin plates using plane-wave excitation. However, experimental results for finite plates are known to diverge from theory, especially near grazing angles. An experimental setup has been developed in order …


Hykss: Hybrid Keyword And Semantic Search, Andrew J. Zitzelberger Aug 2011

Hykss: Hybrid Keyword And Semantic Search, Andrew J. Zitzelberger

Theses and Dissertations

The rapid production of digital information makes the task of locating relevant information increasingly difficult. Keyword search alleviates this difficulty by retrieving documents containing keywords of interest. However, keyword search suffers from a number of issues such ambiguity, synonymy, and the inability to handle semantic constraints. Semantic search helps resolve these issues but is limited by the quality of annotations which are likely to be incomplete or imprecise. Hybrid search, a search technique that combines the merits of both keyword and semantic search, appears to be a promising solution. In this work we introduce HyKSS, a hybrid search system driven …


The Formation And Stability Of Radical-Molecule And Radical-Radical Complexes And Their Importance In Atmospheric Processes, Jared M. Clark Aug 2011

The Formation And Stability Of Radical-Molecule And Radical-Radical Complexes And Their Importance In Atmospheric Processes, Jared M. Clark

Theses and Dissertations

This research explores the role that radical-molecule complexes play in the chemistry of Earth's atmosphere. The formation of such complexes can have direct and pronounced effects on the reaction and product outcome of atmospheric chemical reactions. Some attention is also given to the formation of radial-radical pre-reactive complexes in the HO + ClO system. Peroxy radicals (RO2) can form stable complexes with polar compounds such as H2O, NH3, and CH3OH. For the simplest RO2 radical, HO2, complex formation (e.g., HO2-H2O, HO2-NH3, and HO2-722;CH3OH) gives rise to a significant increase in the HO2 self-reaction rate constant. Although this phenomenon has been …


Scaling Carbon Nanotube Localization By Floating Potential Dielectrophoresis: An Enabling Geometry, Brian S. Davis Aug 2011

Scaling Carbon Nanotube Localization By Floating Potential Dielectrophoresis: An Enabling Geometry, Brian S. Davis

Theses and Dissertations

Dielectrophoresis has been used as a technique for the parallel localization and alignment of both semiconducting and metallic carbon nanotubes (CNTs) at junctions between electrodes. A variation of this technique known as Floating Potential Dielectrophoresis (FPD) allows for a self-limiting number of CNTs to be localized at each junction, on a massively parallel scale. However, the smallest FPD geometries to date are restricted to conductive substrates and have a lower limit on floating electrode size. We present a geometry which eliminates this lower limit and enables FPD to be performed on non-conducting substrates. We also discuss experiments clarifying the self-limiting …


Characterization Of The Desorption Electrospray Ionization Mechanism Using Microscopic Imaging Of The Sample Surface, Michael Craig Wood Aug 2011

Characterization Of The Desorption Electrospray Ionization Mechanism Using Microscopic Imaging Of The Sample Surface, Michael Craig Wood

Theses and Dissertations

Desorption electrospray ionization (DESI) is an ambient ionization technique for mass spectrometry. This solvent based desorption ion source has wide applicability in surface analysis with minimal sample preparation. Interest in improving detection limits, broadening applications, and increasing the spatial resolution for chemical imaging has led to studies of the DESI mechanism. An inverted microscope has been used to image interactions between the DESI spray and test analytes on a glass surface. Microscopic images recorded with millisecond time resolution have provided important insights into the processes governing analyte transport and desorption. These insights are the basis of a rivulet-based model for …