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Total Syntheses Of (+)-Geldanamycin, (-)-Ragaglitazar, And (+)-Kurasoin A And Phase-Transfer-Catalyzed Asymmetric Alkylation, Erik J. Hicken Nov 2005

Total Syntheses Of (+)-Geldanamycin, (-)-Ragaglitazar, And (+)-Kurasoin A And Phase-Transfer-Catalyzed Asymmetric Alkylation, Erik J. Hicken

Theses and Dissertations

Geldanamycin possesses various biological activities as seen in the NCI 60 cell line panel (13 nM avg., 70 nM SKBr-3 cells). The predominant mode of action providing these unique results arises from the ability of geldanamycin (GA) to bind to the chaperone heat shock protein 90 (Hsp90). Despite its complicated functionality, the first total synthesis of GA was accomplished, which included two new reactions developed specifically to address the stereochemical features. The final step in the synthesis of GA was a demethylation-oxidation sequence to generate the desired para-quinone. This step could only be accomplished with HNO3/AcOH, producing GA in …


Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell Oct 2005

Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell

Faculty Publications

Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. Methods: In this study, ovariectomized (OVX) female Long-Evans rats were fed either an isoflavone-rich diet (Phyto-600) or an isoflavone-free diet (Phyto-free). We examined the effects of soy isoflavones on metabolism by measuring body weights, food/water intake, adipose tissue weights as well as serum leptin levels. Also, circulating isoflavone levels were quantified. During chemically induced estrous, nociceptive thresholds were recorded. Then, the animals were subjected to a stressor and stress hormone levels were …


Using Genetic Algorithms To Map First-Principles Results To Model Hamiltonians: Application To The Generalized Ising Model For Alloys, Gus L. W. Hart, Volker Blum, Michael J. Walorski, Alex Zunger Oct 2005

Using Genetic Algorithms To Map First-Principles Results To Model Hamiltonians: Application To The Generalized Ising Model For Alloys, Gus L. W. Hart, Volker Blum, Michael J. Walorski, Alex Zunger

Faculty Publications

The cluster expansion method provides a standard framework to map first-principles generated energies for a few selected configurations of a binary alloy onto a finite set of pair and many-body interactions between the alloyed elements. These interactions describe the energetics of all possible configurations of the same alloy, which can hence be readily used to identify ground state structures and, through statistical mechanics solutions, find finite-temperature properties. In practice, the biggest challenge is to identify the types of interactions which are most important for a given alloy out of the many possibilities. We describe a genetic algorithm which automates this …


Specific Heat And Thermodynamic Properties Of Metallic Systems: Instrumentation And Analysis, Brian E. Lang Oct 2005

Specific Heat And Thermodynamic Properties Of Metallic Systems: Instrumentation And Analysis, Brian E. Lang

Theses and Dissertations

A small-scale adiabatic calorimeter has been constructed as part of a larger project to study nano-particles and to facilitate specific heat measurements on samples where it is difficult to obtain enough material to run on the current large-scale adiabatic apparatus. This calorimeter is designed to measure sample sizes of less than 0.8 cc over a temperature range from 13 K to 350 K. Specific heat results on copper, sapphire, and benzoic acid show the accuracy of the measurements to be better than ±0.4% for temperatures higher than 50 K. The reproducibility of these measurements is generally better than ±0.25%. Experimental …


Historical Land Cover Impacts On Water Quality In The Provo River Watershed, 1975 - 2002, Fredric James Donaldson Oct 2005

Historical Land Cover Impacts On Water Quality In The Provo River Watershed, 1975 - 2002, Fredric James Donaldson

Theses and Dissertations

The Provo River watershed has experienced land cover change over the past several decades. Land cover influences water quality inasmuch as land cover determines the type and quantity of non-point source (NPS) pollutants that may enter the water. This study examines the historical impacts of land cover changes on water quality in the Provo River using remote sensing and statistical analysis. Statistical correlations and linear regressions were used to study the relationship between various land cover types and water quality variables for six years between 1975 and 2002. This thesis supports research finding myriad impacts of urban land cover on …


The Role Of Cavitation In Acoustically Activated Drug Delivery, Mario A. Diaz, Ghaleb A. Husseini, William G. Pitt, Eric S. Richardson, Douglas A. Christensen Oct 2005

The Role Of Cavitation In Acoustically Activated Drug Delivery, Mario A. Diaz, Ghaleb A. Husseini, William G. Pitt, Eric S. Richardson, Douglas A. Christensen

Faculty Publications

The triblock copolymer, Pluronic P105, has been found to be an ideal ultrasonically activated drug delivery vehicle because it forms micelles with hydrophobic polypropylene oxide cores that sequester hydrophobic drugs (Fig. 1). These micelles release their contents upon the application of low frequency ultrasound [1]such that drugs can be released specifically at the ultrasonicated region (Fig. 2). Such ultrasonically controlled release has been effective against cancer cells in vitro [2] and in vivo [3]. This poster presents our results showing that collapse cavitation is associated with drug release. Cavitation is generally divided into two types of behavior. Stable cavitation is …


Full Issue Fall 2005 Oct 2005

Full Issue Fall 2005

Inscape

No abstract provided.


Daughters, Hear The Music, Erin Gong Oct 2005

Daughters, Hear The Music, Erin Gong

Inscape

No abstract provided.


Masaki Miyake. Civilization And Time, Andrew Targowski Oct 2005

Masaki Miyake. Civilization And Time, Andrew Targowski

Comparative Civilizations Review

No abstract provided.


Cultural Relativism Or Covert Universalism? The Metaethics Of Multiculturalism, Joseph Thompson Oct 2005

Cultural Relativism Or Covert Universalism? The Metaethics Of Multiculturalism, Joseph Thompson

Comparative Civilizations Review

No abstract provided.


Phylogenetic Analysis Of Large Sequence Data Sets, Hyrum Carroll, Mark J. Clement, Keith Crandall, Quinn O. Snell Oct 2005

Phylogenetic Analysis Of Large Sequence Data Sets, Hyrum Carroll, Mark J. Clement, Keith Crandall, Quinn O. Snell

Faculty Publications

Phylogenetic analysis is an integral part of biological research. As the number of sequenced genomes increases, available data sets are growing in number and size. Several algorithms have been proposed to handle these larger data sets. A family of algorithms known as disc covering methods (DCMs), have been selected by the NSF funded CIPRes project to boost the performance of existing phylogenetic algorithms. Recursive Iterative Disc Covering Method 3 (Rec-I-DCM3), recursively decomposes the guide tree into subtrees, executing a phylogenetic search on the subtree and merging the subtrees, for a set number of iterations. This paper presents a detailed analysis …


Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly Sep 2005

Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly

Theses and Dissertations

Polymeric materials have seen increasing use as microfluidic device substrates due to their low cost and the simplicity of templated fabrication procedures. I showed that poly(methyl methacrylate) (PMMA) microdevices could be enclosed in a boiling water bath, which allowed the seal to form more quickly than in conventional approaches, and enabled microchannels to remain hydrated throughout the bonding process. Microchip capillary electrophoresis (µ-CE) devices were fabricated using water-based enclosure, and a mixture of fluorescently labeled amino acids was separated in 30 s in these microchips. To create more robust capillary electrophoresis (CE) microdevices with improved separation performance, phase-changing sacrificial materials …


Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin Sep 2005

Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin

Theses and Dissertations

The Golden Throne Quadrangle is located within Capitol Reef National Park, south-central Utah. Geologic mapping of this 1:24,000 scale 7.5 minute quadrangle began in 2003 as the National Parks Service desired to have geologic maps at this scale produced within the park. Stratigraphically, ten bedrock formations and ten Quaternary deposits are exposed within the Golden Throne Quadrangle. Geologic formations range in age from Permian to Jurassic. This map contains details not included on previous geologic maps including; the members of the Carmel, Chinle, and Moenkopi Formations. Additionally, the Page Sandstone is herein mapped as an independent unit. Structurally the Golden …


Structure Elucidation Of Bioactive Compounds Isolated From Endophytes Of Alstonia Scholaris And Acmena Graveolens, Nicholas James Hundley Sep 2005

Structure Elucidation Of Bioactive Compounds Isolated From Endophytes Of Alstonia Scholaris And Acmena Graveolens, Nicholas James Hundley

Theses and Dissertations

Alstonia scholaris is an evergreen tree native to Southeast Asia and Australia. It is commonly used as a medicinal plant throughout these regions. In the present study, an endophyte of the genus Xylaria was isolated from a stem of Alstonia scholaris, its mycelia and exudate extracted, and the extract assayed for growth inhibition of HeLa cancer cells in vitro. Several known compounds were isolated and identified based on NMR, infrared, and mass spectral data. The compounds identified are 19,20-epoxycytochalasin C; 19,20epoxycytochalasin D; and xylobovide. Two other compounds, fusaric acid and dehydrofusaric acid, were discovered in an endophyte of the Hypocreales …


An Acyl Radical Cascade Model For The Total Synthesis Of Lyconadin A, Seth W. Grant Sep 2005

An Acyl Radical Cascade Model For The Total Synthesis Of Lyconadin A, Seth W. Grant

Theses and Dissertations

Lyconadin A (1) is a structurally unique Lycopodium alkaloid with antitumor properties, isolated from the club moss Lycopodium complanatum. We are developing a synthetic route to 1 based on a novel 7-exo-trig/6-exo-trig acyl radical cascade cyclization. The synthesis of model acyl radical cascade precursor 23 will be presented. Key features of this synthesis include the suppression of competing elimination during the alkylation of a hindered phenethyl bromide and the use of a lactone as a precursor to a compound bearing two differentially protected primary alcohols. An account of our studies on the model acyl radical cascade cyclization (23 to 24 …


Val D. Rust Radical Origins: Early Mormon Converts And Their Colonial Ancestors, Jenny Hale Pulsipher Sep 2005

Val D. Rust Radical Origins: Early Mormon Converts And Their Colonial Ancestors, Jenny Hale Pulsipher

BYU Studies

Val D. Rust. Radical Origins: Early Mormon Converts and Their Colonial Ancestors. Urbana: University of Illinois Press, 2004


Full Issue, Byu Studies Sep 2005

Full Issue, Byu Studies

BYU Studies

No abstract provided.


The Principles Of The Proclamation: Ten Years Of Help, Richard G. Wilkins Sep 2005

The Principles Of The Proclamation: Ten Years Of Help, Richard G. Wilkins

BYU Studies

On September 23, 1995, while presiding at the first general Relief Society meeting held since he was sustained as prophet, seer, revelator, and President of The Church of Jesus Christ of Latter-day Saints, President Gordon B. Hinckley read “The Family: A Proclamation to the World.” The Proclamation was prefaced by these remarks:

With so much of sophistry that is passed off as truth, with so much of deception concerning standards and values, with so much of allurement and enticement to take on the slow stain of the world, we have felt to warn and forewarn. In furtherance of this, we …


Effect Of Melatonin And Dopamine In Site Specific Phosphorylation Of Phosducin In Intact Retina, Arinzechukwu Okere Nkemdirim Aug 2005

Effect Of Melatonin And Dopamine In Site Specific Phosphorylation Of Phosducin In Intact Retina, Arinzechukwu Okere Nkemdirim

Theses and Dissertations

Phosducin (Pdc) is a 28 kDa binding partner for the G protein beta gamma subunit dimer (G-beta-gamma) found abundantly in the photoreceptor cells of the retina and pineal gland. In the retina, light-dependent changes in cAMP and Ca2+ control the phosphorylation of Pdc at serine 73 and 54, respectively, which in turn controls the binding of Pdc to G protein beta gamma subunit dimer . G protein beta gamma subunit dimer binding has been proposed to facilitate light-driven transport of G protein beta gamma subunit dimer from the site of phototransduction in the outer segment of the photoreceptor cell to …


The Effect Of A Lingual Magnet On Fricative Production: An Acoustic Evaluation Of Placement And Adaptation, Andrea Lynn Weaver Aug 2005

The Effect Of A Lingual Magnet On Fricative Production: An Acoustic Evaluation Of Placement And Adaptation, Andrea Lynn Weaver

Theses and Dissertations

Much of speech kinematics research is conducted by attaching a device to the articulators. However very little research has been conducted to determine what influence these devices may have on the perceptual and acoustic characteristics of speech. This study examined the effect of placing a small magnet on the tongue of ten normal adult speakers while reading a sentence containing /s/ and "sh" in initial, medial and final position. Two different placements of 10 and 15 mm from the tip of the tongue were analyzed. Data were taken before magnet placement, immediately after magnet placement, after 5 minutes of conversation, …


Generation Of Biomarkers From Anthrax Spores By Catalysis And Analytical Pyrolysis, Phillip R. Smith Aug 2005

Generation Of Biomarkers From Anthrax Spores By Catalysis And Analytical Pyrolysis, Phillip R. Smith

Theses and Dissertations

Anthrax spores, in weaponized form, are dangerous biological warfare agents. Handheld technology for the rapid detection of anthrax is greatly needed to improve national security. Methods to detect anthrax spores are diverse, with most taking at least an hour for positive identification. A viable option for rapid detection is analytical pyrolysis (AP), which produces chemicals containing taxonomical information (biomarkers). AP methods are reviewed and critically analyzed to show that reproducible detection of anthrax spores in a rapid manner (< 5 min) with a handheld device is not currently possible. A promising alternative to AP is the use of a catalyst to produce biomarkers from anthrax spores with improved selectivity and reproducibility. Catalytic materials having promise for this include platinum, nickel, and superacids. Experiments evaluating several of these materials are described. A biomarker mass spectral library was created, based on information available in the scientific literature, to facilitate analysis and identification of the biomarkers produced experimentally. The RAMFAC algorithm was used to deconvolute chromatographic peaks to produce clean mass spectra and match them against entries in the biomarker library. While the library is not complete, its use with the RAMFAC algorithm enabled detection of many important biomarkers in experiments involving catalytic breakdown of anthrax spores. Experimental results from preliminary tests of several catalysts are presented and discussed. Addition of catalysts in the form of platinum nanoclusters and superacids to bacterial spores in a commercial pyrolyzer effected an increase in the amount of biomarkers produced at mild conditions over traditional pyrolysis methods. Electroformed nickel mesh, on the other hand, demonstrated low catalytic activity for the production of biomarkers, likely due to poor contact of the spores with the mesh. Biomarkers similar to those published in the literature were observed, including dipicolinic acid, picolinic acid, propionamide, acetamide, diketopiperazines, fatty acids, furfuryl alcohol, and DNA bases. A statistically designed factorial study was used to determine the importance of temperature, spore loading, and nanocluster loading on the production of three important biomarkers. The relative importance of these variables differs for each of the three important biomarkers, suggesting they are produced by different reaction mechanisms.


Combating The Banality Of Evil: Portrayals Of The Literary Female Villain In Gã¼Nter Grass's Danziger Trilogie And Novella, Im Krebsgang., Joseph Ephraim Baumgarten Aug 2005

Combating The Banality Of Evil: Portrayals Of The Literary Female Villain In Gã¼Nter Grass's Danziger Trilogie And Novella, Im Krebsgang., Joseph Ephraim Baumgarten

Theses and Dissertations

In Günter Grass's Danzig Trilogy and novella, Im Krebsgang, an antagonistic female type makes a repeated appearance. She appears in the guise of Susi Kater and Luzie Rennwand in Die Blechtrommel, and as Tulla Pokriefke in the other works, Katz und Maus, Hundejahre, and Im Krebsgang. This antagonistic female type is not like other women in these works. A review of Le Deuxième Sexe by feminist Simone de Beauvoir reveals several crucial components contributing to woman's position in society. Most essentially, a woman's natural attributes and (dis)abilities and the conventions of society have enforced her historical submission to man. This …


A Method For Characterizing The Properties Of Industrial Foams, Shaun M. Salisbury Aug 2005

A Method For Characterizing The Properties Of Industrial Foams, Shaun M. Salisbury

Theses and Dissertations

Assessing the effect of foam layers on transport phenomena is of significant interest in many industries, so a method for predicting foam layer properties has been developed. A model of the propagation of radiation from an amplitude-modulated laser beam through a non-absorbing foam layer has been developed using diffusion theory. Measurements predicted by diffusion theory were compared to results generated using Monte Carlo methods for a variety of foam layer properties in both the time-domain and the frequency-domain. The properties that were varied include the layer thickness, the scattering coefficient, and the asymmetry parameter. Layer thicknesses between 8.5 mm and …


Comparing The Effects Of Granivorous Rodents On Persistence Of Indian Ricegrass (Oryzopsis Hymenoides) Seeds In Mixed And Monospecific Seed Patches, Joseph A. Veech, Stephen H. Jenkins Jul 2005

Comparing The Effects Of Granivorous Rodents On Persistence Of Indian Ricegrass (Oryzopsis Hymenoides) Seeds In Mixed And Monospecific Seed Patches, Joseph A. Veech, Stephen H. Jenkins

Western North American Naturalist

In desert environments seeds are often heterogeneously distributed in small patches that vary in number of seed species and in seed density. Because seed harvest by rodents is often density dependent (a larger proportion of seeds is removed from high-density seed patches than from low-density patches), the proportion of residual or post-harvest seeds should be greater in low-density patches. In addition, seed preference can affect harvest. We tested whether the residual proportion of a highly preferred seed (Indian ricegrass, Oryzopsis hymenoides) was less when in a seed patch with a 2nd species (mixed-species patch) than when in a monospecific …


Pollination Needs Of Arrowleaf Balsamroot, Balsamorhiza Sagittata (Heliantheae: Asteraceae), James H. Cane Jul 2005

Pollination Needs Of Arrowleaf Balsamroot, Balsamorhiza Sagittata (Heliantheae: Asteraceae), James H. Cane

Western North American Naturalist

Arrowleaf balsamroot, Balsamorhiza sagittata (Pursh) Nutt, is a common, sometimes dominant, long-lived forb that flowers early in spring from the foothills to upper-montane areas of the northern Rocky Mountains and Intermountain West. Public land managers desire its seed for rangeland rehabilitation. Through manual pollination field trials, the species was found to have a mixed pollination system. It is primarily xenogamous (46% of ovules yielded plump achenes) but partially self-compatible (31% of achenes were plump). Unvisited flower heads formed virtually no mature achenes; only plump achenes contained seeds with endosperm. Freely visited flower heads in 2 populations produced as many achenes …


New Species Of Mentzelia (Loasaceae) And Phacelia (Hydrophyllaceae) From New Mexico, N. Duane Atwood, Stanley L. Welsh Jul 2005

New Species Of Mentzelia (Loasaceae) And Phacelia (Hydrophyllaceae) From New Mexico, N. Duane Atwood, Stanley L. Welsh

Western North American Naturalist

New species of Mentzelia and Phacelia are described from northwestern New Mexico, USA, as Mentzelia todiltoensis, N. Duane Atwood & Stanley L. Welsh, and Phacelia sivinskii N. D. Atwood, sp. nov. The new Mentzelia is compared to M. humilis based on similarities in seed, fruit, leaf, and flower morphology and to M. memorabalis in stem, leaf, and fruit morphology. Phacelia sivinskii is compared to P. constancei N. D. Atwood on the basis of seed, leaf, and flower morphology.


Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, Erik A. Beever, David A. Pyke, Jeanne C. Chambers, Fred Landau, Stanley D. Smith Jul 2005

Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, Erik A. Beever, David A. Pyke, Jeanne C. Chambers, Fred Landau, Stanley D. Smith

Western North American Naturalist

Disturbance in riparian areas of semiarid ecosystems involves complex interactions of pulsed hydrologic flows, herbivory, fire, climatic effects, and anthropogenic influences. We resampled riparian vegetation within ten 10-m × 100-m plots that were initially sampled in 1992 in 4 watersheds of the Snake Range, east central Nevada. Our finding of significantly lower coverage of grasses, forbs, and shrubs within plots in 2001 compared with 1992 was not consistent with the management decision to remove livestock grazing from the watersheds in 1999. Change over time in cover of life-forms or bare ground was not predicted by scat counts within plots in …


Blue Tilapia (Oreochromis Aureus) Predation On Fishes In The Muddy River System, Clark County, Nevada, G. Gary Scoppettone, J. Antonio Salgado, M. Bridget Nielsen Jul 2005

Blue Tilapia (Oreochromis Aureus) Predation On Fishes In The Muddy River System, Clark County, Nevada, G. Gary Scoppettone, J. Antonio Salgado, M. Bridget Nielsen

Western North American Naturalist

No abstract provided.


Inland Fishes Of California By Peter B. Moyle, Andrew L. Sheldon Jul 2005

Inland Fishes Of California By Peter B. Moyle, Andrew L. Sheldon

Western North American Naturalist

No abstract provided.


Variation In Lewisia Kelloggii (Portulacaceae) With Description Of A New Species Endemic To Idaho, Barbara L. Wilson, Valerie D. Hipkins, Edna Rey-Vizgirdas, Thomas N. Kaye Jul 2005

Variation In Lewisia Kelloggii (Portulacaceae) With Description Of A New Species Endemic To Idaho, Barbara L. Wilson, Valerie D. Hipkins, Edna Rey-Vizgirdas, Thomas N. Kaye

Western North American Naturalist

Lewisia kelloggii has been understood as a rare plant with a disjunct range in California and Idaho. Examination of herbarium specimens and analysis of isozymes in 6 Idaho and 7 California populations revealed consistent differences between plants of the 2 states. Fixed differences in alleles at 2 loci (AAT2 and PGI1) distinguished Idaho from California plants. Genetic identities based on isozymes between Idaho and California populations averaged 0.58, lower than the average for congeneric plant species. Idaho plants were smaller than most California plants, but California plants were variable. The most consistent morphological difference between Idaho and California specimens was …