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Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang Dec 2008

Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang

Theses and Dissertations

We developed an approach to the β-thioenamide linkage contained in the S-(2-aminovinyl)cysteine (avCys) residue of thioviridamide.1,2 Kinetic and thermodynamic control of radical additions of thiols to ynamides were studied for the formation of β-thioenamide linkage. Thiyl radicals are electrophilic and ynamides are electron-rich alkynes. This complementary polarity of the radical and acceptor increases the likelihood of a successful radical addition reaction. Because little is known about these types of compounds (β-thioenamides), we were unsure what kinds of yields and stereoselectivities (cis vs. trans) to expect. The adduct stability is another issue to consider. Fortunately, under typical radical addition conditions, the …


Comparison Of Two Training Programs On Acceleration Out Of The Break In American Football, Micah Adam Alba Dec 2008

Comparison Of Two Training Programs On Acceleration Out Of The Break In American Football, Micah Adam Alba

Theses and Dissertations

Athletes of American football need the ability to stop, start, and reach top speed in an efficient manner. Football players on the defensive side of the ball require the skill of stopping a backward run and accelerating to a forward run. This action is termed the break. Football players receive year-round training in an effort to improve performance. Yet, many times, these athletes may not focus specifically on the muscular systems that are unique to the position they play. The law of specificity states that the more specific the training is for the action required, the more beneficial the outcome. …


Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo Dec 2008

Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo

Theses and Dissertations

Swimming performance strongly influences fitness in aquatic organisms and is closely tied to external body morphology. Although this connection has been closely examined at the individual and species level, few studies have focused on this relationship as it pertains to functional group assemblages. Using functional groups based on similarities in habitat use and morphology, I tested the hypothesis that swimming performance can be reliably predicted by functional group composition. I measured swimming performance as burst speed using a simulated predator attack and as prolonged speed using a step-endurance test in a laboratory flume. I measured morphology using geometric morphometric techniques. …


A Population Genetic Study Of Middle Eastern Populations Using Dys 458 Microvariants And Cohen Modal Haplotypes, Enass Nabeel Tinah Dec 2008

A Population Genetic Study Of Middle Eastern Populations Using Dys 458 Microvariants And Cohen Modal Haplotypes, Enass Nabeel Tinah

Theses and Dissertations

A comprehensive population study in the Middle East was conducted using different genetic markers in order to establish a wider genetic profile of the Middle Eastern populations. The main goal of this study was to analyze DNA from samples collected from different locations, and produce genetic motifs and patterns that could be used to identify and distinguish the target populations. This information will allow us to analyze the ancestry of these populations, their interactions through time and space, and the effects these interactions have on the populations' structure. We have collected around 1300 individual samples from different populations in the …


A Correlational Study: The Relationship Between Physical Activity Levels, Physical Self-Worth, And Global Self-Worth In High School Physical Education Students, Ashley Danelle Eyre Dec 2008

A Correlational Study: The Relationship Between Physical Activity Levels, Physical Self-Worth, And Global Self-Worth In High School Physical Education Students, Ashley Danelle Eyre

Theses and Dissertations

The purpose of this study was to determine the relationship between physical activity levels, physical self-worth, and its sub-domains; (a) skill, (b) body attractiveness, (c) fitness and conditioning, and (d) strength, and overall global self-worth in high school students. One-Hundred and sixty-seven students (male = 66;female = 101) from the western United States, ages 13-18, participated in this study. Each participant completed a minimum of four days of physical activity (PA) data collection and completed the self-worth questionnaire. Pedometers were used to collect PA levels, calculating mean step counts, and the Children and Youth Physical Self-Perception Profile (CY-PSPP) was used …


The Effects Of Excess Corticosterone On Lkb1 And Ampk Signaling In Skeletal Muscle Of Rats, Gary N. Nakken Dec 2008

The Effects Of Excess Corticosterone On Lkb1 And Ampk Signaling In Skeletal Muscle Of Rats, Gary N. Nakken

Theses and Dissertations

Cushing's syndrome and glucocorticoid therapy lead to central obesity, insulin resistance, and symptoms of altered energy regulation similar to those observed in the metabolic syndrome. We hypothesized that excess glucocorticoids alter energy sensing/signaling in skeletal muscle through mediation of the LKB1/AMPK signaling pathway. To test this hypothesis, three 100 mg pellets of corticosterone were implanted subcutaneously in each of nine rats for two weeks. Responses were compared with sham operated controls fed ad libitum or food restricted to produce the body weights similar to the treatment group rats. After the treatment period, animals were anesthetized and the right gastrocnemius-plantaris and …


Using Pedometers As A Valid Method Of Determining Physical Activity Intensity Level, Alan M. Groves Dec 2008

Using Pedometers As A Valid Method Of Determining Physical Activity Intensity Level, Alan M. Groves

Theses and Dissertations

As researchers explore the benefits of using pedometers to assess physical activity they are discovering that intensity of physical activity may be estimated from steps per minute (SPM). The purpose of this study was to determine the SPM and kilocalories (kcals) expended associated with moderate physical activity in middle school students (12 - 14 years old). Methods: Ninety-three (49 boys, 44 girls) middle school youth between the ages of 12 and 14, walked on a treadmill at four different speeds (4.0, 4.8, 5.64, and 6.4 km/h) for three minutes at each speed. Each participant wore a pedometer in order to …


Using Sport Science To Improve Coaching: A Case Study Of The American Record Holder In The Women’S Hammer Throw, Iain Hunter, Erin Gilreath, Larry W. Judge Dec 2008

Using Sport Science To Improve Coaching: A Case Study Of The American Record Holder In The Women’S Hammer Throw, Iain Hunter, Erin Gilreath, Larry W. Judge

Faculty Publications

Conclusions from biomechanical data can make a significant difference in the performance of athletes in the hammer throw if properly understood by coaches. By utilizing this scientific approach to the hammer throw event, the throws coach will be able to determine more accurate adjustments and devise training stimuli to better accommodate the athlete. In this case study, we have attempted to bridge the gap between the researcher and the coach in our approach to teaching the hammer throw, by integrating biomechanical analysis. We have employed the use of video analysis as an essential part of our coaching/teaching system. This USATF …


A Simple, Anatomically Based Correction To The Conventional Ankle Joint Center, Dustin A. Bruening, Ashlie N. Crewe, Frank L. Buczek Dec 2008

A Simple, Anatomically Based Correction To The Conventional Ankle Joint Center, Dustin A. Bruening, Ashlie N. Crewe, Frank L. Buczek

Faculty Publications

Background

Conventional motion analysis studies define the ankle joint center as the midpoint between the most medial and lateral aspects of the malleoli, yet research points toward a more distal joint center location. The purpose of this study was to develop and evaluate an anatomically based correction that would move the conventional ankle joint center to a more accurate location.

Methods

Lower extremity radiographs from 30 pediatric patients were analyzed retrospectively. An offset between the conventional and more accurate ankle joint centers was measured and correlated to other common anatomical measures based on conventional skin mounted marker positions. The best …


Evolution Of Picornaviruses: Impacts Of Recombination And Selection, Nicole Noel Lewis-Rogers Nov 2008

Evolution Of Picornaviruses: Impacts Of Recombination And Selection, Nicole Noel Lewis-Rogers

Theses and Dissertations

Picornaviruses are responsible for some of the most common and debilitating diseases affecting humans and animals worldwide. The objectives of this dissertation research were (1) estimate phylogenetic relationships among 11 picornavirus genera and within three species: foot-and-mouth disease virus (FMDV: Aphthovirus) which afflicts cloven-hoofed animals and human rhinovirus A and B (HRV: Enterovirus) which cause the common cold; (2) better understand the impact recombination has on genomic organization and evolution; (3) characterize where positive and purifying selection has occurred in proteins and how selection has influenced phenotype. The dissertation includes four studies. The first chapter provides an overview of the …


Hair, Feces And Breath Isotope Fractionation In Alpacas (Llama Pacos), Llamas (Llama Glama) And Guanacos (Llama Guanacoe) From Bolivia And Chile, Lino Constancio Lopez Lopez Nov 2008

Hair, Feces And Breath Isotope Fractionation In Alpacas (Llama Pacos), Llamas (Llama Glama) And Guanacos (Llama Guanacoe) From Bolivia And Chile, Lino Constancio Lopez Lopez

Theses and Dissertations

This study was conducted to determinate carbon and nitrogen isotope fractionation in Bolivian and Chilean alpaca, llama and guanaco, hair, breath, plasma and feces. We also wanted to determine forage selection for these camelids using stable isotope technology. From the data, niche feeding and diet selection habits will determinate based on fecal composition. Bolivian sites were located near the high snow Altiplano Mountains at Tomarapi, Sajama, and at the Technical University Oruro's research center at Condoriri, Bolivia. Chilean samples were collected at INIA's (Instituto Nacional de Investigacion Agropecuaria) Kampenaike Research Station, Punta Arenas, Chile. Bolivian alpacas and llamas were 3 …


Specific Compartmentalization Of Iga Ascs In Mouse Salivary Glands Via Differential Expression Of Chemokines And Chemokine Receptors, Yuet Ching Law Nov 2008

Specific Compartmentalization Of Iga Ascs In Mouse Salivary Glands Via Differential Expression Of Chemokines And Chemokine Receptors, Yuet Ching Law

Theses and Dissertations

The mucosal system, which forms a barrier between internal organ systems and the external environment, is frequently exposed to pathogenic microorganisms. Immunoglobulin A (IgA) antibody secreting cells (ASCs) localize in the lamina propria, and produce IgA antibodies which help protect mucosal tissues. The concept of a common mucosal immune system in which IgA ASCs have the ability to populate any mucosal site has been proposed (1, 2). However, recent research has suggested that IgA ASCs primed in different mucosal sites might possess different sets of chemokine receptors, and therefore migrate specifically to particular mucosal locations (3). In this study, the …


Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell Nov 2008

Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell

Faculty Publications

High dietary intake of selenium or isoflavones reduces risk factors for prostate cancer. We tested whether combined supplementation of these two dietary components would reduce prostate cancer risk factors in rats more than supplementation of each component individually. Methods Male Noble rat pups were exposed from conception to diets containing an adequate (0.33-0.45 mg/kg diet) or high (3.33-3.45 mg/kg) concentration of selenium as Se-methylselenocysteine and a low (10 mg/kg) or high (600 mg/kg) level of isoflavones in a 2 x 2 factorial design. Pups consumed their respective diets until sacrifice at 35, 100, or 200 days. Male Noble rat breeders, …


Photocycloaddition Of Allenes, Crystal Ward Nov 2008

Photocycloaddition Of Allenes, Crystal Ward

Theses and Dissertations

For the past ten years the Fleming research group has been involved in the research of allene compounds. We have explored the synthesis of allenes as well as several reactions involving allenes, such as oxidation and nitrene addition. Recently, we have explored the synthesis and photochemistry of allenic alcohols tethered to silicon. There are literature examples using allenes in synthesis, but very few examples exist using allenes in photochemical cycloaddition reactions. We have found that a diisopropylallenyloxy(cinnamyloxy)silane derivative undergoes [2+2] photochemical cycloaddition to produce a cyclobutylsilane product when irradiated for 60-75 minutes.


Commercial Evaluation Of A Continuous Micronutrient Fortification Process For Nixtamal Tortillas, Michael L. Dunn, Sergio O. Serna-Saldivar, Diana Sanchez-Hernandez, Robert W. Griffin Nov 2008

Commercial Evaluation Of A Continuous Micronutrient Fortification Process For Nixtamal Tortillas, Michael L. Dunn, Sergio O. Serna-Saldivar, Diana Sanchez-Hernandez, Robert W. Griffin

Faculty Publications

The corn tortilla plays an integral role in the Mexican diet and is an ideal vehicle for micronutrient fortification. Approximately 60% of corn tortillas in Mexico are produced from nixtamal, with the remainder prepared from masa flour. A process for continuous fortification of nixtamal tortillas was evaluated in two commercial mills in Mexico. A commercial powder dosifier was used to add micronutrient premix containing iron, zinc, folic acid, niacin, riboflavin, and thiamin to nixtamal (1 g/kg) as it was milled. After training and preliminary sampling, mills produced fortified tortillas unassisted for four weeks. Masa flow rates over a four-day period …


Physical Mapping Of Ribosomal Genes In New World Members Of The Genus Chenopodium Using Fluorescence In Situ Hybridization, Maria C. Sederberg Oct 2008

Physical Mapping Of Ribosomal Genes In New World Members Of The Genus Chenopodium Using Fluorescence In Situ Hybridization, Maria C. Sederberg

Theses and Dissertations

The genus Chenopodium contains many economically important species in the New World, but is relatively understudied and poorly understood, especially in terms of evolutionary relationships. A better understanding of the structure of this genus could significantly help in breeding efforts on its cultivated members, notably the tetraploid C. quinoa and also certain varieties of C. berlandieri, also tetraploid. Of special concern is determining which diploid weed species are the most likely ancestors for C. quinoa, C. berlandieri, and the other tetraploid members of subsection Cellulata. The phylogeny can be understood in part by examining the ribosomal RNA loci and observing …


Calculating Expected Dna Remnants From Ancient Founding Events In Human Population Genetics, Nathan C. Sheffield, Keith A. Crandall, Andrew Stacey Oct 2008

Calculating Expected Dna Remnants From Ancient Founding Events In Human Population Genetics, Nathan C. Sheffield, Keith A. Crandall, Andrew Stacey

Faculty Publications

Background- Recent advancements in sequencing and computational technologies have led to rapid generation and analysis of high quality genetic data. Such genetic data have achieved wide acceptance in studies of historic human population origins and admixture. However, in studies relating to small, recent admixture events, genetic factors such as historic population sizes, genetic drift, and mutation can have pronounced effects on data reliability and utility. To address these issues we conducted genetic simulations targeting influential genetic parameters in admixed populations. Results- We performed a series of simulations, adjusting variable values to assess the affect of these genetic parameters on current …


Many Species In One: Dna Barcoding Overestimates The Number Of Species When Nuclear Mitochondrial Pseudogenes Are Coamplified, Michael F. Whiting, Hojun Song, Keith A. Crandall, Jennifer E. Buhay Sep 2008

Many Species In One: Dna Barcoding Overestimates The Number Of Species When Nuclear Mitochondrial Pseudogenes Are Coamplified, Michael F. Whiting, Hojun Song, Keith A. Crandall, Jennifer E. Buhay

Faculty Publications

Nuclear mitochondrial pseudogenes (numts) are nonfunctional copies of mtDNA in the nucleus that have been found in major clades of eukaryotic organisms.


Resulting Shifts In Percentile And Standard Placements After Comparison Of The Bod Pod And Dxa, Timothy Heden, Steve Shepard, John Smith, Kay Covington, James D. Lecheminant Sep 2008

Resulting Shifts In Percentile And Standard Placements After Comparison Of The Bod Pod And Dxa, Timothy Heden, Steve Shepard, John Smith, Kay Covington, James D. Lecheminant

Faculty Publications

Int J Exerc Sci 1(3) : 113-124, 2008. The purpose of this study was to determine the validity of the BOD POD® when compared to the DXA and if placement on a percentile chart and standard table is affected by any differences between the two measures. A total of 244 (27.7 ± 10.8 yrs, 77.3 ± 16.1 kg, 171.4 ± 10.1 cm, 26.31 ± 5.42 BMI) males and females between the ages of 18 and 52 were recruited to participate in this study. The participant’s body fat percentage (%BF) was tested in random order on the BOD POD® and DXA …


Wnt5a Signaling Independently Of The Planar Cell Polarity Pathway Resulting In Convergent Extension And Neural Tube Closure During Vertebrate Development, Jared James Barrott Aug 2008

Wnt5a Signaling Independently Of The Planar Cell Polarity Pathway Resulting In Convergent Extension And Neural Tube Closure During Vertebrate Development, Jared James Barrott

Theses and Dissertations

Vertebrate development is regulated by cellular communication by mechanisms of cell fate and cell behavior. These crucial mechanisms are regulated by cellular signaling and in the case of cell fate, cellular signaling results in transcription of developmentally important genes. Communication between cells can also result in regulation of cell behavior by acting on cytoskeletal elements rather than nuclear factors. One of the cellular signals that regulate both cell fate and cell behavior is the family of Wnt signaling molecules. Wnt5a is one of 19 Wnt molecules and has been previously demonstrated to play critical roles in many important processes in …


Determining The Role Of Wnt5a Signaling In Embryonic Limb Outgrowth Via Clonal Analysis, Whitney Herrod Sowby Aug 2008

Determining The Role Of Wnt5a Signaling In Embryonic Limb Outgrowth Via Clonal Analysis, Whitney Herrod Sowby

Theses and Dissertations

The exact mechanisms that regulate limb outgrowth the mouse embryo are unknown. Although there are several models, we favor a hypothesis where cells become polarized by signals secreted from the AER which orient their cell migration and/or divisions causing limb outgrowth. Clonal analysis has provided a mechanism to study cell behavior. We have generated a targeting construct containing the Fgf8 inhibitor, Sprouty2, in order to generate mutant clones for behavioral analyses in the limb. In order to more effectively study clonal behavior we report the modification of a novel clonal analysis approach, exo-utero surgery. We have modified, enhanced and proven …


The Antioxidant Defense Network: Synergistic Combinations To Prevent Oxidative Damage, Amy Marie Clement Aug 2008

The Antioxidant Defense Network: Synergistic Combinations To Prevent Oxidative Damage, Amy Marie Clement

Theses and Dissertations

One of the matchless ironies of the human body is its requirement for the highly reactive oxygen molecule, which has been clearly implicated in many diseases and the aging processes. Oxidants produced by metabolic processes damage cells by starting chemical chain reactions including oxidation of DNA and proteins as well as lipid peroxidation. Damage to DNA can cause mutations and lead to cancer if not reversed by DNA repair mechanisms. Damage to proteins causes enzyme inhibition, denaturation and protein degradation. Lipid peroxidation can cause cell lysis as well as creating mutagenic and carcinogenic by-products. The human body contains antioxidants and …


I. Thermodynamics And Magnetism Of Cu2ocl2 Ii. Repairs To Microcalorimeter The "2"S Are Subscripts, And The Second 2 Is Preceded By A Lower Case L, Not A One, Thomas J. Parry Aug 2008

I. Thermodynamics And Magnetism Of Cu2ocl2 Ii. Repairs To Microcalorimeter The "2"S Are Subscripts, And The Second 2 Is Preceded By A Lower Case L, Not A One, Thomas J. Parry

Theses and Dissertations

Adiabatic calorimetry provides accurate and precise specific heat (Cp) data. From this data, thermodynamic functions may be calculated. Cu2OCl2, melanothallite, became of interest as part of a study of a particular thermochemical cycle. The experimental specific heat data and the calculated thermodynamic functions are reported here. Free energies of formation, calculated from the thermodynamic functions, suggest the particular cycle of interest with this compound as an intermediate is not feasible; uncertainty as to the accuracy of CuO and CuCl2 data used in the calculations indicate further study may be necessary. Upon collection of the specific heat data, an antiferromagnetic transition …


Domain Duplication, Darwinian Selection, And The Origin Of The Globulin Seed Storage Proteins, Nathaniel S. Cannon Aug 2008

Domain Duplication, Darwinian Selection, And The Origin Of The Globulin Seed Storage Proteins, Nathaniel S. Cannon

Theses and Dissertations

The seed storage globulins found among virtually all spermatophytes comprise a multi-gene family of proteins with ancient evolutionary origins. The two main groups of storage globulins include the legumins (11S) and vicilins (7S), both of which play a main role in protein deposition and storage in the seed endosperm. Composed of two cupin domains (bicupin), these proteins have been recently noted not only for their close structural relationships among the two subfamilies (7S and 11S) but also for their similarity to other proteins such as germin-like proteins (GLP's), bacterial oxalate decarboxylases, and other cupin containing proteins. Previous studies have investigated …


Cellular And Matrix Changes In Articular Cartilage Of The Disproportionate Micromelia Mouse Model Of Osteoarthritis, Crystal Noelle Smaldone Aug 2008

Cellular And Matrix Changes In Articular Cartilage Of The Disproportionate Micromelia Mouse Model Of Osteoarthritis, Crystal Noelle Smaldone

Theses and Dissertations

Osteoarthritis (OA) is a degenerative joint disease that affects more than 60% of Americans 65 and older. Because human subjects and samples are not readily available for research, animal models are an invaluable resource for the study of OA. Disproportionate micromelia (Dmm) is one such model that develops OA early in life due to a deletion in the c-propeptide of the Col2a1 gene. Light microscope analysis of the articular cartilage in Dmm has been completed, but is insufficient to show the cellular effects of the deletion mutation in Dmm in adequate detail. The present study explores the changes that occur …


A Radical Conjugate Addition Approach To The Total Synthesis Of Celogentin C, Steven G. Capps Aug 2008

A Radical Conjugate Addition Approach To The Total Synthesis Of Celogentin C, Steven G. Capps

Theses and Dissertations

The synthesis of five chiral DBFOX (dibenzofuran-oxazoline) ligands with either aryl or benzyl substituents will be presented. The requisite amino alcohols were obtained with high enantioselectivity either commercially (DBFOX/Bn), via Sharpless asymmetric aminohydroxylation (DBFOX/Nap, DBFOX/t-BuPh, DBFOX/Pip), or via phase-transfer catalyzed asymmetric alkylation (DBFOX/MeNap). These ligands, complexed with Mg(NTf2)2, were used as Lewis acid promoters of enantioselective radical conjugate additions to α/β-unsaturated nitro-amides/esters. A summary of these results is presented and discussed. These findings led us to believe that our initial binding model between metal, ligand, and substrate was flawed. Thus, we figured that if we started with a functionality known …


Regulators Of G-Protein Signaling, Rgs13 And Rgs16, Are Associated With Cxcl12-Mediated Cd4+ T Cell Migration, Lijin Xia Aug 2008

Regulators Of G-Protein Signaling, Rgs13 And Rgs16, Are Associated With Cxcl12-Mediated Cd4+ T Cell Migration, Lijin Xia

Theses and Dissertations

Chemokines are important chemical signals that guide lymphocyte movement within the immune system and promote the organization and functions of germinal centers (GCs) in the secondary lymphoid tissues. Previous studies have shown that GC T cells exhibit high expression of chemokine receptor 4, CXCR4, but that these cells are unable to migrate to the ligand for this receptor, the chemokine CXCL12. This “migratory paralysis” to CXCL12 was found to be correlated with the expression of two Regulators of G-protein Signaling, RGS13 and RGS16 in the GC T cells. The objective of my research was to determine whether RGS13 and RGS16 …


Decline In A Dominant Invertebrate Species Contributes To Altered Carbon Cycling In A Low-Diversity Soil Ecosystem, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall Aug 2008

Decline In A Dominant Invertebrate Species Contributes To Altered Carbon Cycling In A Low-Diversity Soil Ecosystem, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall

Faculty Publications

Low-diversity ecosystems cover large portions of the Earth's land surface, yet studies of climate change on ecosystem functioning typically focus on temperate ecosystems, where diversity is high and the effects of individual species on ecosystem functioning are difficult to determine. We show that a climate-induced decline of an invertebrate species in a low-diversity ecosystem could contribute to significant changes in carbon © cycling. Recent climate variability in the McMurdo Dry Valleys of Antarctica is associated with changes in hydrology, biological productivity, and community composition of terrestrial and aquatic ecosystems. One of the greatest changes documented in the dry valleys is …


Spectroscopic Study Of Compressible Mobile Phase And Stationary Phase Behavior In Chromatography, Lawrence R. Baker Jul 2008

Spectroscopic Study Of Compressible Mobile Phase And Stationary Phase Behavior In Chromatography, Lawrence R. Baker

Theses and Dissertations

Raman spectroscopy, laser-induced fluorescence, and sum-frequency generation (SFG) spectroscopy are used to investigate the behavior of compressible mobile phases and stationary phases under a variety of chromatographic conditions. Efforts to understand and optimize separations employing compressible mobile phases have been limited by a lack of understanding of the mobile phase density gradient. Mobile phase compressibility leads to gradients in linear velocity and solute retention and affects separation speed and efficiency, especially in packed columns. This work describes on-column density measurement of CO2, a common carrier fluid for SFC and SGC, in packed capillary columns using Raman microspectroscopy. On-column detection by …


Differential Expression And Functional Characterization Of Alpha3 Beta2 Neuronal Nicotinic Acetylcholine Receptors, John Hideo Mizukawa Jul 2008

Differential Expression And Functional Characterization Of Alpha3 Beta2 Neuronal Nicotinic Acetylcholine Receptors, John Hideo Mizukawa

Theses and Dissertations

Neuronal nicotinic acetylcholine receptors (nAChRs) are expressed in both the periperhal and central nervous systems, and are involved in pre-, post-, and non-synaptic control of neuronal activation. In the brain, these receptors play an important role in a variety of physiological processes such as cognition, development, learning, and memory formation. Malfunction of these receptors have been implicated in neurodegenerative diseases like Alzheimer's disease (AD), schizophrenia, and Parkinson's disease. To date, 17 different nAChR subunits, including α2-α7 and β2-β4, have been cloned that can form homo- and/or hetero-pentameric ionotropic receptors. The unique combinations of subunit pentamers manifest in distinct functional receptors. …