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Habitat Affinities Of Rodents In Northeastern Nevada Rangeland Communities, J. Kent Mcadoo, Mack R. Barrington, Mark A. Ports Aug 2006

Habitat Affinities Of Rodents In Northeastern Nevada Rangeland Communities, J. Kent Mcadoo, Mack R. Barrington, Mark A. Ports

Western North American Naturalist

From May 1978 through September 1980, baseline data for rodent populations were collected by livetrapping in the Saval Ranch area of northeastern Nevada. The objectives of this study were to determine species composition and relative abundance of rodents for the various range sites. The 3 most abundant and uniformly distributed species were deer mice (Peromyscus maniculatus), Great Basin pocket mice (Perognathus parvus), and least chipmunks (Neotamias minimus). Relative abundance indices and densities reported for most species were similar to those reported in other multiyear studies at similar sites. The composition and relative abundance / …

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Ferritin: Mechanistic Studies And Electron Transfer Properties, Bo Zhang Aug 2006

Ferritin: Mechanistic Studies And Electron Transfer Properties, Bo Zhang

Theses and Dissertations

Ferritins are ubiquitous iron storage proteins in living systems. Although much is known about the iron deposition process in ferritin and a mechanism has been developed, several important issues still remain unknown. One lingering question is the less than stoichiometric quantities of hydrogen peroxide detected in previous studies on animal ferritins. Extensive experimental data on identifying the species in competition for peroxide equivalents point to a surprising conclusion that H2O2 generated in the ferroxidase reaction is consumed by amine buffers that are commonly employed in in vitro ferritin studies, while non-nitrogen containing buffers, such as acetate, phosphate, and carbonate, do …

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The Phylogeography Of Prosopium In Western North America, Becky Akiko Miller Aug 2006

The Phylogeography Of Prosopium In Western North America, Becky Akiko Miller

Theses and Dissertations

The mountain whitefish (Prosopium williamsoni) has been largely overlooked in population genetic analyses despite its wide distribution in discrete drainage basins in western North America for over four million years. Its closest sister taxa the Bear Lake whitefish (P. abyssicola), Bonneville cisco (P. gemmifer), and Bonneville whitefish (P. spilonotus) are found only in Bear Lake Idaho-Utah and were also included in the analyses. A total of 1,334 cytochrome b and 1,371 NADH dehydrogenase subunit 2 sequences from the Bonneville Basin, the Columbia River Sub-basin, the lower Snake River Sub-basin, the upper Snake River Sub-basin, the Green River Basin, the Lahontan …

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Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski Aug 2006

Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski

Theses and Dissertations

A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade …

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Classification Of Neuronal Nicotinic Acetylcholine Receptors In Rat Ca1 Hippocampal Interneuron Subpopulations Defined By Calcium-Binding Protein Mrna Expression, Richard M. Burgon Jul 2006

Classification Of Neuronal Nicotinic Acetylcholine Receptors In Rat Ca1 Hippocampal Interneuron Subpopulations Defined By Calcium-Binding Protein Mrna Expression, Richard M. Burgon

Theses and Dissertations

In this study, the single-cell relative quantitative mRNA expression of three Calcium-binding proteins (CaBPs; calbindin, calretinin, parvalbumin) and eight nicotinic acetylcholine receptor (nAChR) subunits (alpha2-alpha5, alpha7, beta2-beta4) from interneurons from the stratum radiatum or stratum oriens within the CA1 region of rat hippocampi was analyzed using quantitative real time RT-PCR. Eighty-seven percent of the interneurons examined expressed CaBP mRNA. Parvalbumin mRNA was detected in 64%, while calbindin and calretinin expression was detected in 26% and 40% of interneurons, respectively. CaBP expression was not exclusive; the average number of CaBP mRNA detected per interneuron of the 47 interneurons examined for CaBP …

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Predicting Maize Yield, Nutrient Concentration And Uptake In P And K Fertilized Soils: Pressurized Hot Water And Other Alternatives To Mehlich I Extraction In Guatemala Soils, Heather Mae Hunsaker Jul 2006

Predicting Maize Yield, Nutrient Concentration And Uptake In P And K Fertilized Soils: Pressurized Hot Water And Other Alternatives To Mehlich I Extraction In Guatemala Soils, Heather Mae Hunsaker

Theses and Dissertations

The inaccessibility and cost of soil testing reduce effectiveness of fertilizer use on small-scale subsistence farms, and inadequate funding promotes adoption of soil tests in developing countries with minimal validation. For example, Mehlich-I extraction of phosphorus (P) currently used extensively in Guatemala may not be suitable for its broad range of soils. At least four alternatives are available but are relatively untested [Bray 1, Mehlich III, Olsen and pressurized hot water (PHW)]. Pressurized hot water is relatively simple and inexpensive, but is not yet tested against other extraction methods under variable P or potassium (K) fertilization levels. To determine whether …

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Structure-Activity Studies Of Glycosphingolipids As Antigens Of Natural Killer T Cells, Randal Donald Goff Jul 2006

Structure-Activity Studies Of Glycosphingolipids As Antigens Of Natural Killer T Cells, Randal Donald Goff

Theses and Dissertations

Glycosphingolipids (GSLs), composed of a polar saccharide head and a lipophilic ceramide tail, are ubiquitous components of the plasma membrane of eukaryotic cells. They serve in many regulatory capacities and have antigenic properties towards natural killer T (NKT) cells of the innate immune system. Critical to the recognition of glycosylceramides by NKT cells are antigen presenting cells (APC), such as dendritic cells, which are responsible for binding, processing, and delivery of ligands to these lymphocytes. This event is mediated by CD1d, a major histocompatibility complex-like protein expressed on the surface of APCs, which binds GSL antigens by the ceramide moiety …

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Case Study Of A Middle School Reader Attending A Separate Reading Class, Amy A. Wilson Jul 2006

Case Study Of A Middle School Reader Attending A Separate Reading Class, Amy A. Wilson

Theses and Dissertations

Despite the prevalence of separate reading classes in middle-level schools across the country, there is much debate about the effectiveness of these courses. Many researchers advocate content-area literacy or interdisciplinary teaming instead, claiming that students do not transfer the skills they learn in reading classes to other subjects. This qualitative case study of one middle school student is an intensive description of a biracial Navajo and Piute teenager who attended a separate reading class. The case study looked at three specific areas of the student's reading in regards to this class: comprehension, motivation, and perception. The student did not transfer …

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Eating Disorder Risk In Subgroups Of College Freshman Women, Karen E. Gochnour Jul 2006

Eating Disorder Risk In Subgroups Of College Freshman Women, Karen E. Gochnour

Theses and Dissertations

The intent of this study was to identify subgroups within the college population having a heightened risk for eating disorders. The information for this analysis was retrieved from an existing data set. The two variables that were compared were self selection of college major at the initial collection during freshman year. The sample size of 1,924 was used to see if subgroups of college majors had a heightened risk. Twenty groups composed of similar majors were studied. The majors of Dance, Dietetics, Physical Education, and Communications had heightened risk according to analysis percentage of each group in the clinical range …

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The Relationship Between Fine Arts Participation And The Emotional Intelligence Of Fifth-Grade Elementary Students, Susan Jean Clark Jul 2006

The Relationship Between Fine Arts Participation And The Emotional Intelligence Of Fifth-Grade Elementary Students, Susan Jean Clark

Theses and Dissertations

Although attempts have been made to justify fine arts education in elementary schools on the basis of various educational and social benefits, the greatest benefit may lie in arts participation's impact on the child's emotional intelligence. A review of published literature related to emotional learning, emotional intelligence, and the benefits of fine arts participation in the elementary school is presented. The resulting synthesis serves as a theoretical framework for the view that emotional learning and expression should be integral components of a child's education and that participation in the arts provides a viable means to that end. A study was …

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Improving The Learning Approach Of College Freshmen And Future Teachers Through Curricular Intervention, Lynna Betty Shin Jul 2006

Improving The Learning Approach Of College Freshmen And Future Teachers Through Curricular Intervention, Lynna Betty Shin

Theses and Dissertations

Students who exercise a deep approach to learning connect classroom content to real-life experiences. To help first-year students develop a deep approach to learning, Brigham Young University offers a program called Freshman Academy. Participants join a "learning community" based on their intended major. As part of this learning community, participants take recommended first-year courses together and engage in service-learning and problem-solving activities. The purpose of this quantitative study was to explore changes in learning approach that followed participation in a Freshman Academy learning community for prospective elementary education majors. These changes were explored through a survey that asked students how …

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Identification, Sequencing, Expression And Evolutionary Relationships Of The 11s Seed Storage Protein Gene In Chenopodium Quinoa Willd., Marie Renee Barrett Balzotti Jul 2006

Identification, Sequencing, Expression And Evolutionary Relationships Of The 11s Seed Storage Protein Gene In Chenopodium Quinoa Willd., Marie Renee Barrett Balzotti

Theses and Dissertations

Quinoa (Chenopodium quinoa) is an Andean crop adapted to harsh environmental conditions and containing a high and well-balanced protein composition. Two seed storage proteins, the 2S albumin and 11S globulin, are the major amino acid reservoirs for the developing seedling. An in-depth study of the genes encoding these proteins is necessary to understand the source of quinoa's protein quality. Our objectives include identification and sequencing of the 11S genomic and cDNA clones, analysis of 11S expression profiles in different quinoa accessions and evaluation of evolutionary relationships between the sequence of the 11S gene in quinoa and homologous genes in other …

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Modeling The Mechanical Effects Of Liquid Mediated Adhesion Between The Human Vocal Folds, Gifford Zach Decker Jul 2006

Modeling The Mechanical Effects Of Liquid Mediated Adhesion Between The Human Vocal Folds, Gifford Zach Decker

Theses and Dissertations

The vocal folds are a complex self-oscillating biological system. In the current research, an equation was developed to model viscous adhesion forces that occur when the collision of the vocal folds results in the formation of a liquid bridge. The adhesion equation was validated using experimental data, and simplified to a one-dimensional approximation with an included correction factor that adjusted the predicted pressure in situations where the one-dimensional approximation was invalid. A non-oscillating vocal fold model with a modeled liquid bridge was used to study stress resulting from viscous adhesion. The vertical normal stress magnitude ranged from about 80 to …

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Simple Sequence Repeat Development, Polymorphism And Genetic Mapping In Quinoa (Chenopodium Quinoa Willd.), David Jarvis Jul 2006

Simple Sequence Repeat Development, Polymorphism And Genetic Mapping In Quinoa (Chenopodium Quinoa Willd.), David Jarvis

Theses and Dissertations

Quinoa is an important, highly nutritional grain crop in the Andean region of South America. DNA markers and linkage maps are important tools for the improvement of underdeveloped crops such as quinoa. The objectives of this study were to (i) develop a new set of SSR markers to augment the number of SSR markers available in quinoa, and (ii) construct a new genetic linkage map of quinoa based on SSRs using multiple recombinant-inbred line (RIL) populations. Here we report the development of 216 new polymorphic SSR markers from libraries enriched for GA, CAA, and AAT repeats, as well as 6 …

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Sequence Analysis Of Pmel17 As Candidate Gene For Causing Rat-Tail Syndrome In Cattle, Benjamin C. Hecht Jul 2006

Sequence Analysis Of Pmel17 As Candidate Gene For Causing Rat-Tail Syndrome In Cattle, Benjamin C. Hecht

Theses and Dissertations

Congenital hypotrichosis in cattle is commonly referred to as "rat-tail" syndrome and is characterized by a dilution of black coat color and morphological changes to the hair shaft and tail switch. Two loci are involved in the inheritance of the rat-tail phenotype, the "extension locus" (MC1R) and an unknown locus. In order to express the rat-tail phenotype the animal must inherit at least one black allele at MC1R and be heterozygous at the unknown locus. The rat-tail locus was previously mapped to an 8.7 cM region of Bos Taurus autosome (BTA) 5. Pmel17 is known to be involved in the …

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"Th' Offense Pardons Itself": Sex And The Church In Othello And Measure For Measure, Jeffrey Wayne Windsor Jul 2006

"Th' Offense Pardons Itself": Sex And The Church In Othello And Measure For Measure, Jeffrey Wayne Windsor

Theses and Dissertations

In 1604, James had newly ascended to the throne and England was now part of Great Britain. The Puritans-largely silenced during Elizabeth's reign-began again to assert political influence and call for reformation to both the state and the church. This is the context in which Shakespeare wrote Othello and Measure for Measure. In both plays, the role of the government in Cyprus or Vienna hinges upon the passions of a single authority figure. Both Angelo and Othello cause political unrest because they mismanage sexuality. In the case of Othello, his unfounded sexual jealousy leads to the death of Desdemona, Emilia, …

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The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie Jul 2006

The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie

Faculty Publications

Calcium-selective ion channels are known to have carboxylate-rich selectivity filters, a common motif that is primarily responsible for their high Ca2+ affinity. Different Ca2+ affinities ranging from micromolar (the L-type Ca channel) to millimolar (the ryanodine receptor channel) are closely related to the different physiological functions of these channels. To understand the physical mechanism for this range of affinities given similar amino acids in their selectivity filters, we use grand canonical Monte Carlo simulations to assess the binding of monovalent and divalent ions in the selectivity filter of a model Ca channel. We use a reduced model where the electrolyte …

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Family Socialization, Religiosity And Young Men's Fatherhood Plans, James Parry Sanders Jul 2006

Family Socialization, Religiosity And Young Men's Fatherhood Plans, James Parry Sanders

Theses and Dissertations

This study examines how family socialization and religiosity are associated with young men's intention to someday become a father. Data from the National Survey of Families and Households are used to measure the influence of family connection, family regulation, family psychological autonomy and public and private religiosity on young men's fatherhood intentions. Family connection and private religiosity are associated with young men's fatherhood plans.

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The Developmental Timing Of Divorce And Adult Children's Romantic Relationship Quality, Abigail Joy Viveiros Jul 2006

The Developmental Timing Of Divorce And Adult Children's Romantic Relationship Quality, Abigail Joy Viveiros

Theses and Dissertations

Understanding the contingencies that explain whether divorce has positive or negative long-term effects for adult children is at the heart of this study. Although previous studies suggest an association between parental divorce and the divorce of adult offspring, less known is about whether the timing of divorce influences the relationship outcomes of adult children. Using a large nationally representative sample in terms of race (N=6,066), eight groups of individuals (males and females from intact homes, males and females who experienced divorce during adolescence, males and females who experienced divorce during middle childhood, and males and females who experienced divorce during …

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Tumor Associated Macrophages In A Mafia Mouse Model, Adrianne Brown Clifford Jul 2006

Tumor Associated Macrophages In A Mafia Mouse Model, Adrianne Brown Clifford

Theses and Dissertations

Recent evidence has shown the important role of macrophages in both tumor development and progression. To investigate the role of macrophages we used a mouse model known as MaFIA (Macrophage Fas Induced Apoptosis) mice that allows for the selective deletion of macrophages. Mice were given melanoma cells at various stages of depletion. Tumor mass was measured and organs were processed for flow cytometry to measure melanoma cell migration. The results show that mice receiving depletion treatment have larger tumor sizes and weights than those mice retaining their macrophage population. We detect metastasis in both the lung and kidney in both …

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Adolescent Leisure Activities As A Moderator Of The Negative Effects Of Family Process On Adolescent Emotional Health, Samuel K. Dahlin Jul 2006

Adolescent Leisure Activities As A Moderator Of The Negative Effects Of Family Process On Adolescent Emotional Health, Samuel K. Dahlin

Theses and Dissertations

The purpose of this study was to investigate whether an adolescent's experience with different types of leisure (achievement, social or time-out) would moderate the negative effects of dysfunctional family process on an adolescent's emotional health. A model was tested that hypothesized that leisure experienced as achievement or social by adolescents would buffer the negative effects of a dysfunctional family. A sample of 243 clinical and non-clinical adolescents completed the Global Severity Index, the Family Assessment Device, and the Leisure Questionnaire. Three regression analyses were run for the whole sample (n=243), the male sample (n=150), and the female sample (n=93). In …

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Phylogeographic Analyses Of Obligate And Facultative Cave Crayfish Species On The Cumberland Plateau Of The Southern Appalachians, Jennifer Elizabeth Buhay Jul 2006

Phylogeographic Analyses Of Obligate And Facultative Cave Crayfish Species On The Cumberland Plateau Of The Southern Appalachians, Jennifer Elizabeth Buhay

Theses and Dissertations

Cave systems and their unique biota are widely viewed as highly endangered, yet very little is known about basic life history, ecology, distributions, habitat requirements, and evolutionary relationships of subterranean species. The crux of the problem in cave studies is the assumption that traditionally defined morpho-species represent distinct evolutionary lineages. Convergence is exhibited in the morphologies of many animal groups, vertebrate and invertebrate, which leads to confusion in diagnosing species' boundaries, geographic distributions, gene flow routes, and imperilment. This dissertation research includes phylogeographic analyses of freshwater cave-dwelling crayfishes in the Southern Appalachians, a global hotspot of subterranean biodiversity. By examining …

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Reading And Writing In Science: How Do The Reform Documents Attend To The Fundamental Sense Of Science Literacy?, Kimberly J. Frandsen Jul 2006

Reading And Writing In Science: How Do The Reform Documents Attend To The Fundamental Sense Of Science Literacy?, Kimberly J. Frandsen

Theses and Dissertations

The purpose of this study was to examine and describe fundamental literacy messages found within three major science reform documents: Science for all Americans: Project 2061 (AAAS, 1990), Benchmarks for Science Literacy (AAAS, 1993), and the National Science Education Standards (NRC, 1996). A qualitative content analysis was performed in an effort to reveal any messages or statements supporting fundamental science literacy. Results from this study indicate that key science reform documents do in fact contain multiple messages supporting the fundamental sense of science literacy, however, the nature of these messages, the quantity, placement and presence of negative literacy statements may …

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Marital Harmony And Conflict: Linkages To Infants' Emotional Regulation, Cardiac Vagal Tone, And Developmental Status At Six- And Nine-Months Of Age, Staci Shizuko Ohmine Jul 2006

Marital Harmony And Conflict: Linkages To Infants' Emotional Regulation, Cardiac Vagal Tone, And Developmental Status At Six- And Nine-Months Of Age, Staci Shizuko Ohmine

Theses and Dissertations

This study examined the linkages between marital harmony and conflict and infants' emotional and physiological regulation abilities and developmental status at six- and nine-months of age. Participants included 93 first-time mothers and their infants (43 males, 50 females) from a Mountain West community. Mothers were asked to complete a battery of questionnaires, including a demographic measure and Braiker and Kelly's (1979) marital quality questionnaire. The revised Bayley Scales of Infant Development (BSID II) and Behavior Rating Scales (BRS) 2nd Edition were administered at six- and nine-months to measure infants' mental and motor development status and emotional regulation abilities. Infants' heart …

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Ecological Investigations Of Chukars In Western Utah, Randy T. Larsen Jul 2006

Ecological Investigations Of Chukars In Western Utah, Randy T. Larsen

Theses and Dissertations

This thesis presents three separate manuscripts in chapter format dealing with the ecology of Chukars (Alectoris chukar) in western North America. All three manuscripts have been formatted for publication in professional journals. Chapter one confirms discovery of ingested lead pellets in Chukars across a broad region of western Utah including all four western counties sampled. Prevalence rates were 1.9% (n=105) for crops and 10.7% (n=75) of gizzards showing no evidence of penetration wounds. Ingestion is likely related to grit size preferences that are consistent with common shot sizes. The second chapter describes watering patterns and water-site selection of Chukars. Chukars …

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Pka As An Upstream Kinase For Lkb1/Strad/Mo25, Seth Taylor Herway Jul 2006

Pka As An Upstream Kinase For Lkb1/Strad/Mo25, Seth Taylor Herway

Theses and Dissertations

The LKB1/STRAD/MO25 complex (LSMK) has been identified as the major upstream kinase for AMP-activated protein kinase (AMPK). PKA phosphorylates LKB1 at the Ser428 residue in humans and Ser431 residue in mice. We investigated PKA as an upstream kinase for LSMK. LKB1 that had been incubated with PKA prior to incubation with AMPK experienced up to a 51% increase in AMPK Kinase activity compared to LKB1 alone (p < 0.05). When blocked with a PKA Inhibitor, the kinase effect of PKA on LKB1 was eliminated. Rat epitrochlearis muscle tissue incubated with epinephrine experienced no increase in AMPK activity compared with controls indicating that epinephrine does not cause AMPK activity in this type of tissue. In conclusion, phosphorylation by PKA can increase the AMPKK activity of LKB1-STRAD-MO25 in vitro. Because LKB1 has been found to be constitutively active, it is postulated that phosphorylation by PKA may act to enhance LKB1-AMPK interaction and thus achieve its effect.

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The Effects Of 3-Phosphoglycerate And Other Metabolites On The Activation Of Amp-Activated Protein Kinase By Lkb1/Strad/Mo25, William John Ellingson Jul 2006

The Effects Of 3-Phosphoglycerate And Other Metabolites On The Activation Of Amp-Activated Protein Kinase By Lkb1/Strad/Mo25, William John Ellingson

Theses and Dissertations

Skeletal muscle contraction results in the phosphorylation and activation of the AMP-activated protein kinase (AMPK) by an upstream kinase, AMPKK. The LKB1-STRAD-MO25 complex is the major AMPKK in skeletal muscle; however, LKB1-STRAD-MO25 activity is not increased by muscle contraction. This relationship suggests that phosphorylation of AMPK by LKB1-STRAD-MO25 during skeletal muscle contraction may be regulated by allosteric mechanisms. In this study we tested an array of metabolites including glucose-6-phosphate (G6P), fructose-6-phosphate (F6P), fructose 1,6-bisphosphate (F1,6-P2), 3-phosphoglycerate (3PG), glucose-1-phosphate (G1P), glucose-1,6-bisphosphate (G1,6-P2), adenosine diphosphate (ADP), carnitine (Carn), acetyl-carnitine (Acarn), inosine monophosphate (IMP), inosine, and ammonia for allosteric regulation. We found that …

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Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham Jul 2006

Jumpstarting Phylogenetic Searches, Jesse Lewis Mecham

Theses and Dissertations

Phylogenetic analysis is a central tool in studies of comparative genomics. When a new region of DNA is isolated and sequenced, researchers are often forced to throw away months of computation on an existing phylogeny of homologous sequences in order to incorporate this new sequence. The previously constructed trees are often discarded, and the researcher begins the search again from scratch. The jumpstarting algorithm uses trees from the prior search as a starting point for a new phylogenetic search. This technique drastically decreases search time for large data sets. This kind of analysis is necessary as researchers analyze tree of …

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Dna-Templated Surface Alignment And Characterization Of Carbon Nanotubes., Huijun Xin Jul 2006

Dna-Templated Surface Alignment And Characterization Of Carbon Nanotubes., Huijun Xin

Theses and Dissertations

Carbon nanotubes are appealing materials for nanofabrication due to their unique properties and structures. However, for carbon nanotubes to be used in mass-fabricated devices, precise control of nanotube orientation and location on surfaces is critical. I have developed a technique to align single-walled carbon nanotubes (SWNTs) on surfaces from a droplet of nanotube suspension under gas flow. Fluid motion studies indicate that alignment is likely due to circulation of SWNTs in the droplet. My work provides a facile method for generating oriented nanotubes for nanodevice applications. I have also devised an approach for localizing SWNTs onto 1-pyrenemethylamine-decorated DNA on surfaces. …

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Enhanced Electrospray Ionization For Mass Spectrometry And Ion Mobility Spectrometry, Li Zhou Jul 2006

Enhanced Electrospray Ionization For Mass Spectrometry And Ion Mobility Spectrometry, Li Zhou

Theses and Dissertations

Electrospray ionization (ESI) has become one of the most commonly used ionization techniques for mass spectrometry (MS) and ion mobility spectrometry (IMS), and efforts continue to improve its performance. ESI-MS is most recognized for its wide application to biomacromolecules where high sensitivity is of paramount importance. However, the major limitation in sensitivity with ESI-MS is due to its low ion transmission efficiency from the ESI source into the sampling orifice and through any stages utilized for transfer of ions from atmosphere to vacuum in the MS. A series of atmospheric pressure ion focusing interfaces were designed and implemented to enhance …

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