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An Xyz Micromanipulator With Three Translational Degrees Of Freedom, Kimberly A. Jensen, Craig P. Lusk, Larry L. Howell May 2006

An Xyz Micromanipulator With Three Translational Degrees Of Freedom, Kimberly A. Jensen, Craig P. Lusk, Larry L. Howell

Faculty Publications

This paper introduces a three degree of freedom XYZ Micromanipulator (XYZM) that is fabricated in the x-y plane and positions components in the x, y, and z directions using three independent linear inputs. The mechanism positions components on a platform using three legs, each composed of a slider mechanism and a parallelogram mechanism.

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The Manuscript Of The Gospel Of Judas, S. Kent Brown May 2006

The Manuscript Of The Gospel Of Judas, S. Kent Brown

BYU Studies

This article discusses the Gospel of Judas, an Early Christian text found in Egypt about 1978 and published in 2006 with much media attention. The discovery of the manuscript of the Gospel of Judas raises questions about the manuscript's origin and if it could have been forged. The author discusses the book's similarities to and differences from the Nag Hammadi texts, Christian documents found in 1945. He describes the manuscript's condition when it was found, its contents, and the effect it may have on scholars' research on early Christianity. He also shares his own experience in viewing ancient papyrus documents …

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Mechanisms Imposing The Vbeta Bias Of V14a Natural Killer T Cells And Consequences For Microbial Glycolipid Recognition, Paul B. Savage, Dasten G. Wei, Shane A. Curran, Luc Teyton, Albert Bendelac May 2006

Mechanisms Imposing The Vbeta Bias Of V14a Natural Killer T Cells And Consequences For Microbial Glycolipid Recognition, Paul B. Savage, Dasten G. Wei, Shane A. Curran, Luc Teyton, Albert Bendelac

Faculty Publications

Mouse and human natural killer T (NKT) cells recognize a restricted set of glycosphingolipids presented by CD1d molecules, including self iGb3 and microbial alpha-glycuronosylceramides. The importance of the canonical Valpha 14-Jalpha18 TCR alphachain for antigen recognition by NKT cells is well recognized, but the mechanisms underlying the Vbeta8, Vbeta7, and Vbeta2 bias in mouse have not been explored. To study the influences of thymic selection and the constraints of pairing with Valpha 14-Jalpha 18, we have created a population of mature T cells expressing Valpha 14-Jalpha 18 TCRalpha chain in CD1d-deficient mice and studied its recognition properties in vitro and …

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No Free Lunch, Bayesian Inference, And Utility: A Decision-Theoretic Approach To Optimization, Christopher Kenneth Monson Apr 2006

No Free Lunch, Bayesian Inference, And Utility: A Decision-Theoretic Approach To Optimization, Christopher Kenneth Monson

Theses and Dissertations

Existing approaches to continuous optimization are essentially mechanisms for deciding which locations should be sampled in order to obtain information about a target function's global optimum. These methods, while often effective in particular domains, generally base their decisions on heuristics developed in consideration of ill-defined desiderata rather than on explicitly defined goals or models of the available information that may be used to achieve them. The problem of numerical optimization is essentially one of deciding what information to gather, then using that information to infer the location of the global optimum. That being the case, it makes sense to model …

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Clustering Of Database Query Results, Kristine Jean Daniels Apr 2006

Clustering Of Database Query Results, Kristine Jean Daniels

Theses and Dissertations

Increasingly more users are accessing database systems for interactive and exploratory data retrieval. While performing searches on these systems, users are required to use broad queries to get their desired results. Broad queries often result in too many items forcing the user to spend unnecessary time sifting through these items to find the relevant results. This problem, of finding a desired data item within many items, is referred to as "information overload". Most users experience information overload when viewing these database query results. This thesis shows that users information overload can be reduced by clustering database query results. …

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Compositional Stability Of Fept Nanoparticles On Sio2/Si During Annealing, Richard R. Vanfleet, B. Yao, R. V. Petrova, K. R. Coffey Apr 2006

Compositional Stability Of Fept Nanoparticles On Sio2/Si During Annealing, Richard R. Vanfleet, B. Yao, R. V. Petrova, K. R. Coffey

Faculty Publications

The loss of Fe due to oxidation or diffusion into the substrate can prevent the successful preparation of well-ordered, stoichiometric, FePt nanoparticles. In this work we report the composition changes during annealing observed for small (<10 nm) FePt nanoparticles on thermally grown SiO2 layers on Si wafer substrates. Additionally, we describe the use of a controlled reducing gas mixture, Ar+H2+H2O, to reduce the loss of Fe.

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Erratum: "Hard Sphere Radial Distribution Function Again", Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak Apr 2006

Erratum: "Hard Sphere Radial Distribution Function Again", Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak

Faculty Publications

Some misprints have been found for parameters given by Eqs. 29 and 30 and the relevant equations in the Appendix.

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Two New Resorcinarenes: A Pyridine & Acetic Acid Ligand For Metal Coordination And A Deep-Cavity Nitroquinoxaline Resorcinarene, Samantha Sizemore Vernetti Apr 2006

Two New Resorcinarenes: A Pyridine & Acetic Acid Ligand For Metal Coordination And A Deep-Cavity Nitroquinoxaline Resorcinarene, Samantha Sizemore Vernetti

Theses and Dissertations

Functionalizing the upper rim of resorcinarene-based cavitands allows a variety of compounds to be synthesized from a single scaffold. Using the upper-rim moieties as ligands for a variety of transition metal ions further increases the versatility of this class of host compounds. A new resorcinarene-based molecule functionalized with four pyridine and acetic acid ligands has been successfully prepared to explore the properties of metal-assembled complexes. To synthesize this compound, tetra(bromomethyl)cavitand was reacted with N-(2-pyridylmethyl)-N-ethylacetate amine to give ethyl acetate pyridine resorcinarene. Hydrolysis of the ester gave acetic acid pyridine resorcinarene (APRes) in good yield. Complexes with Cu2+, Co2+, and Zn2+ …

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A Study Of Islamic Leadership Theory And Practice In K-12 Islamic Schools In Michigan, Adnan Ibrahim Aabed Apr 2006

A Study Of Islamic Leadership Theory And Practice In K-12 Islamic Schools In Michigan, Adnan Ibrahim Aabed

Theses and Dissertations

Effective leadership in Islamic schools involves the incorporation of Islamic principles in the leadership behaviors and practices. With so much literature about the need of Islamic leadership in Islamic institutions in the United States, the problem addressed by the study was whether school principals in Islamic schools exhibited and led these schools according to the principles of Islamic leadership. The study described leadership approaches used by school principals in Islamic schools and how those leadership approaches were influenced by Islamic leadership principles, comparing the Islamic leadership principles derived from the literature with the leadership principles of principals of Islamic schools. …

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Axiomatic Multi-Transport Bargaining: A Quantitative Method For Dynamic Transport Selection In Heterogeneous Multi-Transport Wireless Environments, Qiuyi Duan, Michael A. Goodrich, Charles D. Knutson, Lei Wang Apr 2006

Axiomatic Multi-Transport Bargaining: A Quantitative Method For Dynamic Transport Selection In Heterogeneous Multi-Transport Wireless Environments, Qiuyi Duan, Michael A. Goodrich, Charles D. Knutson, Lei Wang

Faculty Publications

Transport selection mechanisms are designed to facilitate seamless connectivity in heterogeneous multi-transport environments, allowing access to the “best” available transport according to user requirements. Evaluating transport configurations dynamically according to the user’s preferences and Quality of Service (QoS) requirements is a challenging task. This paper describes a quantitative approach that applies the Utility Theorem and Nash’s Bargaining solution to heterogeneous wireless environments. The mathematical model presented generates and adjusts the transport preference list dynamically depending on the degree to which a transport satisfies user preferences and the application’s QoS requirements. We incorporate a negotiation engine using the Axiomatic Multi-Transport Bargaining …

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Periodic Emergence Of Great Historians In The History Of Ancient Greece, Rome And China, Emil Páles, Miroslav Mikulecky Sr. Apr 2006

Periodic Emergence Of Great Historians In The History Of Ancient Greece, Rome And China, Emil Páles, Miroslav Mikulecky Sr.

Comparative Civilizations Review

A periodicity of about 500 years has been discovered in the history of Graeco-Roman and Chinese historiography and documented by means of inferential statistics. Great historians emerged periodically and synchronously in both cultural areas for at least two millennia or longer, although no liaison between historians in the West and Far East is known. It is a surprising fact that this periodicity as well as the times of maximum creativity have been foretold by Babylonian priests, who knew about this rhythm already before 600 B. C. What is the cause of this periodicity and synchronicity is an open question.

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Bibliographical History And Indices Of The Comparative Civilizations Review, 1-50, Michael Palencia-Roth Apr 2006

Bibliographical History And Indices Of The Comparative Civilizations Review, 1-50, Michael Palencia-Roth

Comparative Civilizations Review

No abstract provided.

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The Years Of Rice And Salt By Kim Stanley Robinson, John J. Reilly Apr 2006

The Years Of Rice And Salt By Kim Stanley Robinson, John J. Reilly

Comparative Civilizations Review

No abstract provided.

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Forest Fire Monitoring Using Multiple Unmanned Air Vehicles, Timothy Mclain, Randal W. Beard, Ryan S. Holt, Joseph W. Egbert, Justin M. Bradley, Clark N. Taylor Apr 2006

Forest Fire Monitoring Using Multiple Unmanned Air Vehicles, Timothy Mclain, Randal W. Beard, Ryan S. Holt, Joseph W. Egbert, Justin M. Bradley, Clark N. Taylor

Faculty Publications

The ability to gather and process information on the condition of forest fires is essential to fighting the fires in a cost-effective, safe, and efficient manner. While high-altitude, long-endurance (HALE) unmanned air vehicles (UAVs) are currently used for fire surveillance; they are an expensive and scarce resource. As a proposed alternative, low-altitude, short-endurance (LASE) UAVs offer lower costs, quicker response times, and high- resolution information. In recent years, advances in solid-state sensor and autopilot technology have made LASE UAVs a feasible alternative. This paper overviews a current research project conducted by Brigham Young University and NASA Ames. In the project, …

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Dial 2004 Working Group Report On Acquisition Quality Control, William A. Barrett, Henry Baird, Frank Le Bourgeois, Xiaofan Lin, George Nagy, Steve Simske, Elisa H. Barney Smith Apr 2006

Dial 2004 Working Group Report On Acquisition Quality Control, William A. Barrett, Henry Baird, Frank Le Bourgeois, Xiaofan Lin, George Nagy, Steve Simske, Elisa H. Barney Smith

Faculty Publications

This report summarizes the discussions of the Working Group on Acquisition Quality at the International Workshop on Document Image Analysis for Libraries, Palo Alto, CA, 23-24 January 2004. Acquisition of the image is one of the most time intensive components of forming a digital library, and the quality of the acquisition will affect all later stages of the digital library project. The current state of the art in acquisition is analyzed. Problems and suggested improvements for image acquisition and storage formats and the special problems associated with acquisition from microfilm follows. A list of general suggestions was developed which was …

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Separating Lines Of Text In Free-Form Handwritten Historical Documents, William A. Barrett, Douglas J. Kennard Apr 2006

Separating Lines Of Text In Free-Form Handwritten Historical Documents, William A. Barrett, Douglas J. Kennard

Faculty Publications

We present an approach to finding (and separating) lines of text in free-form handwritten historical document images. After preprocessing, our method uses the count of foreground/background transitions in a binarized image to determine areas of the document that are likely to be text lines. Alternatively, an Adaptive Local Connectivity Map (ALCM) found in the literature can be used for this step of the process. We then use a min-cut/max-flow graph cut algorithm to split up text areas that appear to encompass more than one line of text. After removing text lines containing relatively little text information (or merging them with …

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Gas Chromatography: Mass Spectrometry Of Chemical Agents And Related Interferents, Lailiang Zhai Mar 2006

Gas Chromatography: Mass Spectrometry Of Chemical Agents And Related Interferents, Lailiang Zhai

Theses and Dissertations

One of the main problems encountered in chemical analysis operations in the field is collecting sufficient sample from the source and transferring that sample to the measurement instrument for fast separation and identification. I have been involved in developing a field-portable gas chromatography-mass spectrometry (GC-MS) system with solid phase microextraction (SPME) sampling for point detection of chemical agents. The objective is to minimize the analysis time between sampling and detection of a potential chemical threat. SPME offers a convenient means for sampling gaseous and liquid samples, concentrating the analytes, and transferring the analytes to the injection port of a GC …

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Contrasting Silicic Magma Series In Miocene-Pliocene Ash Deposits In The San Miguel De Allende Graben, Guanajuato, Mexico, Eric H. Christiansen, Bart J. Kowallis, Aaron J. Adams, Oscar Carranza-Castaneda, Wade E. Miller Mar 2006

Contrasting Silicic Magma Series In Miocene-Pliocene Ash Deposits In The San Miguel De Allende Graben, Guanajuato, Mexico, Eric H. Christiansen, Bart J. Kowallis, Aaron J. Adams, Oscar Carranza-Castaneda, Wade E. Miller

Faculty Publications

The San Miguel de Allende graben, Guanajuato, Mexico, contains numerous rhyolitic volcanic ash beds. Electron microprobe and x-ray fluorescence analyses of glass shards from 14 localities, combined with mineralogic, stratigraphic, radiometric, and paleomagnetic data, allow us to correlate the ash beds (and the intervening sedimentary strata and fossils), understand the timing of volcanism, date the age of extension, and better understand the tectonic and volcanic evolution of central Mexico. Our analyses reveal that at least six separate eruptions of rhyolitic ash occurred during the Late Miocene and Pliocene (5-3 Ma) while the San Miguel Allende basin was subsiding. The fallout …

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A Grammatical Description Of The Early Classic Maya Hieroglyphic Inscriptions, Daniel A. Law Mar 2006

A Grammatical Description Of The Early Classic Maya Hieroglyphic Inscriptions, Daniel A. Law

Theses and Dissertations

The purpose of this thesis is to describe the grammatical system of Classical Ch'olti', the language of the Classic Maya hieroglyphic inscriptions, as attested in inscriptions of the Early Classic (approximately AD 200-600). Around 300 Lowland Maya Hieroglyphic inscriptions have been dated to the Early Classic or before, nearly one third of these remain unpublished. Previous work on the monumental inscriptions of the Early Classic (Mathews 1985; Proskouriakoff 1950) has examined Early Classic monuments primarily as works of art. Mora-Marin (2001) examined the language of inscriptions found on early portable texts, a small subset of the corpus here examined. In …

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A Selective Approach To Bandwidth Overbooking, Feng Huang Mar 2006

A Selective Approach To Bandwidth Overbooking, Feng Huang

Theses and Dissertations

Overbooking is a technique used by network providers to increase bandwidth utilization. If the overbooking factor is chosen appropriately, additional virtual circuits can be admitted without degrading quality of service for existing customers. Most existing implementations use a single factor to accept a linear fraction of traffic requests. High values of this factor may cause the degradation of quality of service whereas low overbooking factors will result in underutilization of bandwidth. Network providers often select overbooking factors based only on aggregate average virtual circuit utilization. This paper proposes a selective overbooking scheme based on trunk size and usage profile. Experiments …

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User Datagram Protocol With Congestion Control, Spencer L. Cox Mar 2006

User Datagram Protocol With Congestion Control, Spencer L. Cox

Theses and Dissertations

Communication through the Internet is one of the dominant methods of exchanging information. Whether at an individual or large corporate level the Internet has become essential to gathering and disseminating information. TCP and UDP are the transport layer protocols responsible for transit of nearly all Internet communications. Due to the growth of real-time audio and video applications, UDP is being used more frequently as a transport protocol. As UDP traffic increases potential problems arise. Unlike TCP, UDP has no mechanism for congestion control leading to wasted bandwidth and poor performance for other competing protocols. This thesis defines a congestion control …

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Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake Mar 2006

Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake

Theses and Dissertations

Learning algorithms based on the Fourier transform attempt to learn functions by approximating the largest coefficients of their Fourier representations. Nearly all previous work in Fourier-based learning has been in the theoretical realm, where properties of the transform have made it possible to prove many interesting learnability results. The real-world usefulness of Fourier-based methods, however, has not been thoroughly explored. This thesis explores methods for the practical application of Fourier-based learning. The primary contribution of this thesis is a new search algorithm for finding the largest coefficients of a function's Fourier representation. Although the search space is exponentially large, empirical …

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Browser-Based Trust Negotiation, Cameron Morris Mar 2006

Browser-Based Trust Negotiation, Cameron Morris

Theses and Dissertations

Trust negotiation allows two parties on the Internet to establish trust in each other according to the digital credentials thateach other possesses. Traditionally, trust negotiation uses certificates as digital credentials. However, certificates make trust negotiation difficult to use since people rarely have certificates available to them, and they must physically possess and secure all needed certificates in order to negotiate. To avoid these problems, this thesis proposes that credential authorities negotiate on behalf of the user. This thesis defines BrowserBased Trust Negotiation (BBTN) as a method for negotiating with credential authorities using the Secure Assertion Markup Language (SAML).

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Human Interfaces For Cooperative Control Of Multiple Vehicle Systems, Jisang Sun Mar 2006

Human Interfaces For Cooperative Control Of Multiple Vehicle Systems, Jisang Sun

Theses and Dissertations

This thesis presents a human interface which helps users efficiently allocate multiple unmanned ground vehicles (UGVs) cooperating to accomplish timing-sensitive missions in an urban environment. The urban environment consists of obstacles and a hazardous region. The obstacles represent a "no-go zone" while the hazardous region represents a high-risk area. The main object of this problem is to minimize the team operational cost while satisfying timing constraints. Operational costs for individual vehicles are based on risk and power consumption, and are calculated using path length and vehicle velocity. In this thesis, three types of timing constraints are considered: simultaneous arrival, tight …

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Encryption Of Computer Peripheral Devices, Kelly Robert Norman Mar 2006

Encryption Of Computer Peripheral Devices, Kelly Robert Norman

Theses and Dissertations

Computer peripherals, such as keyboards, scanners, printers, cameras, and Personal Data Assistants (PDAs) typically communicate with a host PC via an unencrypted protocol, leaving them vulnerable to eavesdropping techniques, such as keyloggers. An encryption system was developed that is simple enough to be used in peripherals that do not have large amounts of processing power and memory. A software driver loaded in the operating system of the host computer communicates with a simple 8-bit microcontroller in the peripheral device. The driver handles key generation, key exchange, and provides decrypted data to the operating system. A key exchange protocol allows the …

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Cracking And Roughness Of Asphalt Pavements Constructed Using Cement-Treated Base Materials, Jonathan Russell Hanson Mar 2006

Cracking And Roughness Of Asphalt Pavements Constructed Using Cement-Treated Base Materials, Jonathan Russell Hanson

Theses and Dissertations

While cement treatment is a proven method for improving the strength and durability of soils and aggregates, cement hydration causes shrinkage strains in the cement-treated base (CTB) that can lead to reflection cracking in asphalt surfaces. Cracking may then cause increased pavement roughness and lead to poor ride quality. The overall purpose of this research was to utilize data collected through the Long-Term Pavement Performance (LTPP) program to investigate the use and classification of CTB layers and evaluate the relative impact of cement content on the development of roughness and cracking in asphalt concrete (AC) pavements constructed using CTB layers. …

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Exploring Cultural Competence In The Lived Experience Of Instructional Designers, Paul Clinton Rogers Mar 2006

Exploring Cultural Competence In The Lived Experience Of Instructional Designers, Paul Clinton Rogers

Theses and Dissertations

There has been a limited amount of research concerning culture and online education. Although human beings have the ability to transcend past and current environments, helping professions are recognizing the influence of cultural epistemologies on themselves and those they intend to serve. The purpose of this study was to explore the nature of additional challenges and concerns present when designing online instruction in a cross-cultural context. The data collected in this study stands as preliminary work to creating a substantive theory regarding the importance of cultural influences in the thinking, practice and lived experience of instructional designers, specifically those who …

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Mineral-Scale Sr Isotopic Study Of Plagioclase In The Mafic Dikes Of The North American Wall And The Diorite Of The Rockslides, Yosemite Valley, California., Wendy Rae Nelson Mar 2006

Mineral-Scale Sr Isotopic Study Of Plagioclase In The Mafic Dikes Of The North American Wall And The Diorite Of The Rockslides, Yosemite Valley, California., Wendy Rae Nelson

Theses and Dissertations

The North American Wall mafic dikes and the diorite of the Rockslides mafic complex in the intrusive suite of Yosemite Valley show evidence of mixing with their host granites as well as with earlier components. Whole rock major element variation diagrams indicate the mafic rocks mixed with a more silicic component, but extrapolating to the silica end member does not yield the same result with each element. Trace element concentrations show a wide variation in concentration of Cr and Ni, with two samples showing enrichment in Cr (>300 ppm) and Ni (~44 ppm) compared to other samples (Cr =13-94 …

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What Does It Mean To Preservice Mathematics Teachers To Anticipate Student Responses?, Matthew M. Webb Mar 2006

What Does It Mean To Preservice Mathematics Teachers To Anticipate Student Responses?, Matthew M. Webb

Theses and Dissertations

Lesson study is a form of professional development for teachers adopted in recent years from Japan. Introducing lesson study to U.S. teachers and researchers has been the focus of most of the literature on this subject. Much of the literature outlines how lesson study works and describes its essential features. One of the features of lesson study is anticipating student responses, also known as anticipating student thinking. Anticipating student responses is passingly described in lesson study literature. This research was conducted to understand what it means to anticipate student responses for preservice mathematics teachers in a lesson study group. Lesson …

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Membrane-Based Protein Preconcentration Microfluidic Devices, Yi Li Mar 2006

Membrane-Based Protein Preconcentration Microfluidic Devices, Yi Li

Theses and Dissertations

Interest in microchip capillary electrophoresis (CE) is growing due to the rapid analysis times provided and small sample input requirements. However, higher-concentration samples are typically needed because of the small (~pL) detection volumes in these devices. I have made membrane-based protein preconcentration systems in capillary and microchip designs to increase the detectability of low-concentration biological samples. A photopolymerized ion-permeable membrane interfaced with a microchannel in poly(methyl methacrylate) (PMMA) formed the preconcentrator. When a voltage was applied between the sample reservoir and the ionically conductive membrane in a capillary-based system, R-phycoerythrin was concentrated more than 1,000 fold, as determined by laser-induced …

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