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Ultrasound-Induced Phase Change Of Emulsion Droplets For Targeted Gene And Drug Delivery, James R. Lattin Nov 2012

Ultrasound-Induced Phase Change Of Emulsion Droplets For Targeted Gene And Drug Delivery, James R. Lattin

Theses and Dissertations

This dissertation explores the potential of using perfluorocarbon emulsion droplets to add an ultrasound-sensitive element to drug delivery systems. These emulsion droplets may be induced to vaporize with ultrasound; during the rarefactional phase of an ultrasound wave, the pressure around the droplets may fall below the vapor pressure of the liquid forming the emulsion, providing a thermodynamic potential for vaporization. This ultrasound-induced phase change of the emulsion droplet could release therapeutics attached to the droplet surface or aid in drug delivery due to mechanical effects associated with vaporization and expansion, similar to the ability of cavitating bubbles to aid in …

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Beyond Gel Electrophoresis: Microfluidic Separations, Fluorescence Burst Analysis, And Dna Stretching, Kevin D. Dorfman, Scott B. King, Daniel W. Olson, Joel D. P. Thomas, Douglas R. Tree Nov 2012

Beyond Gel Electrophoresis: Microfluidic Separations, Fluorescence Burst Analysis, And Dna Stretching, Kevin D. Dorfman, Scott B. King, Daniel W. Olson, Joel D. P. Thomas, Douglas R. Tree

Faculty Publications

This review addresses methods for obtaining sequence information directly from unamplified genomic length DNA. Our generic starting point is a large piece of DNA that contains many thousands of base pairs (kilobase pairs, kbp) or even millions of base pairs (megabase pairs, Mbp). We would like to determine the genomic distance between two repeats of a given sequence, indicated by the red dots on the coiled DNA molecule in Figure 1. Let us consider the case where these sequences are restriction sites, which can be selectively cut using proteins known as restriction enzymes. For decades, gel electrophoresis served as the …

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The Nest Predator Assemblage For Songbirds In Mono Lake Basin Riparian Habitats, Quresh S. Latif, Sacha K. Heath, Grant Ballard Nov 2012

The Nest Predator Assemblage For Songbirds In Mono Lake Basin Riparian Habitats, Quresh S. Latif, Sacha K. Heath, Grant Ballard

Western North American Naturalist

Because nest predation strongly limits avian fitness, ornithologists identify nest predators to inform ecological research and conservation. During 2002–2008, we used both video-monitoring of natural nests and direct observations of predation to identify nest predators of open-cup nesting riparian songbirds along tributaries of Mono Lake, California. Video cameras at 50 nests of 3 songbird species and direct observations of additional nests confirmed 10 distinct nest-predator species and suggested one additional species. Video-monitored nests experienced reduced predation rates, and video observations mainly captured nestling predation, even though predation rates were higher for nonvideo-monitored nests during the egg period. These findings suggest …

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Population Abundance And Sex Ratio Of The Viviparous Freshwater Fish Poeciliopsis Baenschi (Poeciliidae) Throughout Its Range In Western Mexico, J. Jaime Zúñiga-Vega, Ana L. Hernández-Rosas, Alejandro Molina-Moctezuma, Hibraim A. Pérez-Mendoza, Fernanda R. Rodríguez-Reyes, Yolotzin M. Bravo-Espinosa, Héctor Espinosa-Pérez Nov 2012

Population Abundance And Sex Ratio Of The Viviparous Freshwater Fish Poeciliopsis Baenschi (Poeciliidae) Throughout Its Range In Western Mexico, J. Jaime Zúñiga-Vega, Ana L. Hernández-Rosas, Alejandro Molina-Moctezuma, Hibraim A. Pérez-Mendoza, Fernanda R. Rodríguez-Reyes, Yolotzin M. Bravo-Espinosa, Héctor Espinosa-Pérez

Western North American Naturalist

We estimated population abundance and sex ratio for a freshwater live-bearing fish species (Poeciliopsis baenschi) that inhabits fluvial systems in western Mexico. We conducted mark-recapture experiments in 6 distinct populations. We used both our catch data as well as estimates of capture probability to calculate the number of individuals per unit water volume for adult males, adult females, and juveniles. Overall, abundance varied among sites from 23.8 individuals · m–3 to 363.2 individuals · m–3. In most of our study sites, the estimated sex ratio was markedly biased toward females (up to 11 females per …

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Survival Of Translocated Greater Sage-Grouse Hens In Northeastern California, Chad B. Bell, T. Luke George Nov 2012

Survival Of Translocated Greater Sage-Grouse Hens In Northeastern California, Chad B. Bell, T. Luke George

Western North American Naturalist

Translocation success of Greater Sage-Grouse (Centrocercus urophasianus) is generally measured by documenting whether translocated individuals survive and reproduce at the release site. However, demographic parameters, such as annual survival of translocated individuals, provide a more accurate measure of translocation success. We translocated 60 female sage-grouse from Oregon and Nevada to Clear Lake National Wildlife Refuge, California, during 2005–2010 to augment a small population of resident grouse. We radio-marked each translocated female and a sample of resident female sage-grouse, recorded their locations, and monitored their survival at monthly intervals over the study period. We observed most (55/60) translocated birds …

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Hispid Pocket Mice In Tallgrass Prairie: Abundance, Seasonal Activity, Habitat Association, And Individual Attributes, Glennis A. Kaufman, Dawn M. Kaufman, Donald W. Kaufman Nov 2012

Hispid Pocket Mice In Tallgrass Prairie: Abundance, Seasonal Activity, Habitat Association, And Individual Attributes, Glennis A. Kaufman, Dawn M. Kaufman, Donald W. Kaufman

Western North American Naturalist

Hispid pocket mice (Chaetodipus hispidus) are found from the grasslands of the Great Plains to the deserts of the southwestern United States, but the natural history and ecology of this species have not been described in native tallgrass prairie at the eastern edge of its range. We initiated an ongoing long-term study of small mammals on Konza Prairie Biological Station, Kansas (a Long-Term Ecological Research [LTER] site), in autumn 1981. Our sampling scheme for 14 LTER sites was a 20-station trapline; small mammals were sampled in autumn and spring for 30 years and in summer for a shorter …

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Biodiversity, Water Chemistry, Physical Characteristics, And Anthropogenic Disturbance Gradients Of Sandstone Springs On The Colorado Plateau, Rebecca H. Weissinger, Dustin W. Perkins, Eric C. Dinger Nov 2012

Biodiversity, Water Chemistry, Physical Characteristics, And Anthropogenic Disturbance Gradients Of Sandstone Springs On The Colorado Plateau, Rebecca H. Weissinger, Dustin W. Perkins, Eric C. Dinger

Western North American Naturalist

Springs located on the Colorado Plateau are highly threatened and represent a small percentage of the landscape; yet they are disproportionately important to diverse native flora and fauna. The relationships between anthropogenic disturbance, aquatic macroinvertebrate species composition, and environmental variables at these springs have received little study. We selectively visited 40 sandstone springs in southeastern Utah and southwestern Colorado to span a range of impacts. We classified the springs into impact categories based on a spring impact score, and we measured biodiversity (aquatic macroinvertebrates), water chemistry (nutrients, dissolved O2, pH, specific conductivity, temperature, turbidity, coliform bacteria [Escherichia …

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End Matter, Vol. 72 No. 3 Nov 2012

End Matter, Vol. 72 No. 3

Western North American Naturalist

No abstract provided.

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The Diet Of Western Burrowing Owls In An Urban Landscape, Lynne A. Trulio, Philip Higgins Nov 2012

The Diet Of Western Burrowing Owls In An Urban Landscape, Lynne A. Trulio, Philip Higgins

Western North American Naturalist

While we know much about the diet of Western Burrowing Owls (Athene cunicularia hypugaea) in many of their more natural habitats, little is known about their diets in urban environments. We analyzed pellets and prey remains collected at burrows used by Burrowing Owls living in urban grasslands in Santa Clara County, California. We hypothesized that the composition of prey species in the diet of these urban owls would differ from that of owls living in agricultural and more-natural western habitats and, in particular, that rodents would be a smaller component of the diet. We found the invertebrate-to-vertebrate ratio …

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Cui-Ui Reproductive Success From Potential Egg Deposition To Larval Emigration, G. Gary Scoppettone, Peter H. Rissler Nov 2012

Cui-Ui Reproductive Success From Potential Egg Deposition To Larval Emigration, G. Gary Scoppettone, Peter H. Rissler

Western North American Naturalist

From 1985 to 2006, we tracked cui-ui, Chasmistes cujus, survival from potential egg deposition of migrating spawners to emigrating larvae. Tahoe sucker larvae emigrated to Pyramid Lake the same time as cui-ui larvae, but cui-ui was the predominant catostomid larvae we captured. Survival of cui-ui larvae ranged from 0.46% to 21.17%, declining significantly with decreased flow and increased number of spawners (P < 0.01). Mean total length of emigrating larvae ranged from 11.5 to 12.6 mm and may have been affected by stream flow. Removal of impediments to upstream migrating cui-ui spawners, along with sufficient stream flows, may enhance early life-stage survival.


Desde 1985 hasta 2006, rastreamos la supervivencia de peces cui-ui, Chasmistes cujus,de una posible deposición de huevos de hembras migratorias a larvas emigrantes. Las larvas del pez Tahoe sucker emigraron al Lago Pirámide al mismo tiempo que …

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Spatial And Temporal Variation Of Dissolved Oxygen And Ecosystem Energetics In Devils Hole, Nevada, Melody J. Bernot, Kevin P. Wilson Nov 2012

Spatial And Temporal Variation Of Dissolved Oxygen And Ecosystem Energetics In Devils Hole, Nevada, Melody J. Bernot, Kevin P. Wilson

Western North American Naturalist

Devils Hole, a unique ecosystem in the Mojave Desert, is home to a few dominant species of algae and invertebrates as well as the endangered Devils Hole pupfish,Cyprinodon diabolis. With consistently high water temperature (33.5 °C/93 °F) and low dissolved oxygen (O2) concentration (about 2.5 mg O2 ⋅ L–1), organisms are at the extremes of their physiological limits, and production of O2 by microbial biofilms is essential to ecosystem stability. Water column O2 concentrations were measured from July 2008 to March 2010 in the deep pool and shallow shelf habitats of Devils …

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Ecology And Population Dynamics Of Sclerocactus Mesae-Verdae (Boissev. & C. Davidson) L.D. Benson, Janet J. Coles, Karin L. Decker, Tamara S. Naumann Nov 2012

Ecology And Population Dynamics Of Sclerocactus Mesae-Verdae (Boissev. & C. Davidson) L.D. Benson, Janet J. Coles, Karin L. Decker, Tamara S. Naumann

Western North American Naturalist

The population dynamics of Sclerocactus mesae-verdae were documented annually in 3 plots over 20 years in southwestern Colorado. Demographic studies of this duration are rare but they are necessary to gain a more accurate estimate of population trends in long-lived desert species. Sclerocactus mesae-verdae was federally listed as threatened in 1979; this study was initiated in 1986 with the objective of determining whether Colorado populations were growing, declining, or stable. Data collected yearly around 1 May included diameter, vigor, and flower/fruit counts for 1629 stems belonging to 659 plants. We used regression analysis to estimate the mean, variance, and average …

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Inundation Depth, Duration, And Temperature Influence Fremon Cottonwood (Populus Fremontii) Seedling Growth And Survival, L. C. Auchincloss, J. H. Richards, C. A. Young, M. K. Tansey Nov 2012

Inundation Depth, Duration, And Temperature Influence Fremon Cottonwood (Populus Fremontii) Seedling Growth And Survival, L. C. Auchincloss, J. H. Richards, C. A. Young, M. K. Tansey

Western North American Naturalist

Fremont cottonwood (Populus fremontii) is an early successional foundation species found in riparian forest ecosystems in the North American Southwest. Along rivers, the upper limit of the seedling establishment zone depends on the proximity of seedling roots to the declining water table. The lower limit is a function of the maximum elevation of inundation or scour. Fremont cottonwood seedlings are likely to experience short-term (1- to 5-week) inundation during their first year of growth under both natural and human-influenced hydrologic regimes. Previous studies show that inundation can account for more than 70% of seedling mortality during this time. …

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Influence Of Relictual Species On The Morphology Of A Hybridizing Oak Complex: An Analysis Of The Quercus X Undulata Complex In The Four Corners Region, Ross A. Mccauley, Brenna J. Christie, Erik L. Ireland, Rae A. Landers, Haley R. Nichols, Matthew T. Schendel Nov 2012

Influence Of Relictual Species On The Morphology Of A Hybridizing Oak Complex: An Analysis Of The Quercus X Undulata Complex In The Four Corners Region, Ross A. Mccauley, Brenna J. Christie, Erik L. Ireland, Rae A. Landers, Haley R. Nichols, Matthew T. Schendel

Western North American Naturalist

The genus Quercus represents an important component of the scrublands and low forests of the Four Corners area of northeastern Arizona, southeastern Utah, southwestern Colorado, and northwestern New Mexico. The area is dominated by the widespread Quercus gambelii, although relictual and marginal populations of Q. turbinella and Q. havardii are also present. Hybridization among these 3 species is common, leading to much variability in phenotypic traits, and this hybridization forms part of the widespread complex of hybrid oaks recognized as Q. x undulata.Multivariate analysis of leaf morphology was performed in 9 populations, representing the various taxa and levels of …

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Olfactory Detection Of Caches Containing Wildland Versus Cultivated Seeds By Granivorous Rodents, Jennifer L. Hollander, Stephen B. Vander Wall, William S. Longland Nov 2012

Olfactory Detection Of Caches Containing Wildland Versus Cultivated Seeds By Granivorous Rodents, Jennifer L. Hollander, Stephen B. Vander Wall, William S. Longland

Western North American Naturalist

We conducted a study to examine the ability of granivorous rodents to detect caches made with wildland (native and nonnative) and cultivated seeds at 3 locations in western Nevada with different vegetation types and rodent community structures. We established artificial caches containing either 2 or 3 species of wildland seeds or cultivated seeds. Five seed species were tested at each site. Under dry conditions, rodents found caches containing cultivated seeds much more rapidly than caches containing wildland seeds. Wet conditions resulted in a similar order of detectability; however, all species of seeds were located much faster in wet conditions than …

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Taxonomic Clarification Of Lupinus Oreganus And Lupinus Biddlei In The Pacific Northwest, Usa, Paul M. Severns, Stephen C. Meyers, Tri Tran Nov 2012

Taxonomic Clarification Of Lupinus Oreganus And Lupinus Biddlei In The Pacific Northwest, Usa, Paul M. Severns, Stephen C. Meyers, Tri Tran

Western North American Naturalist

Through a phylogenetic study using LEGCYC1A nucleotide sequences and a survey of historical botanical literature, we propose clarifications in the nomenclature of Lupinus oreganus and Lupinus biddlei. The former taxon has been incorrectly classified asLupinus sulphureus ssp. kincaidii and recently as L. oreganus var. kincaidii. The latter has recently been incorrectly delimited as L. oreganus var. oreganus.


Se proponen aclaraciones en la nomenclatura de Lupinus oreganus y Lupinus biddlei a través de un estudio filogenético que utiliza secuencias nucleótidas de LEGCYC1A y una revisión de literatura botánica histórica. El primer taxón mencionado se ha clasificado incorrectamente como Lupinus sulphureus …

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Malformed Frogs: The Collapse Of Aquatic Ecosystems By Michael Lannoo, Rosemary A. Burk Nov 2012

Malformed Frogs: The Collapse Of Aquatic Ecosystems By Michael Lannoo, Rosemary A. Burk

Western North American Naturalist

No abstract provided.

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Underwood's Bonneted Bat (Eumops Underwoodi): First Record In The Baja California Peninsula, Patricia Cortés-Calva, Sergio Ticul Álvarez-Castañeda, Julio M. Hernández-Gutirérrez, Marya De La Paz Cuevas Nov 2012

Underwood's Bonneted Bat (Eumops Underwoodi): First Record In The Baja California Peninsula, Patricia Cortés-Calva, Sergio Ticul Álvarez-Castañeda, Julio M. Hernández-Gutirérrez, Marya De La Paz Cuevas

Western North American Naturalist

This paper reports the first record of Eumops underwoodi in the Baja California peninsula. This record expands the species’ distributional range in Mexico along the peninsula. We propose 2 plausible biogeographical explanations. First, the species has the ability to travel across the Gulf of California from the coast of Sonora to the eastern side of the Baja California peninsula and there establish. Second, there is a continuous distribution of the species throughout the mountain ranges that run longitudinally along the Baja California peninsula from the United States border down to the southern tip. We collected one male specimen of E. …

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Front Matter, Vol. 72 No. 3 Nov 2012

Front Matter, Vol. 72 No. 3

Western North American Naturalist

No abstract provided.

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Mechanism Of Action Studies On A New Class Of Anticancer Nucleosides, Megan E. Browning Nov 2012

Mechanism Of Action Studies On A New Class Of Anticancer Nucleosides, Megan E. Browning

Theses and Dissertations

We have completed mechanism of action studies on a new class of anticancer nucleosides typified by a novel nucleoside discovered in our lab, MAP-870. In order to study the mechanism of MAP-870, several experiments were completed on a colorectal adenocarcinoma cell line, HT-29, including trypan blue cell count, sulforhodamine B assays, flow cytometry of cell cycle, propidium iodide incorporation, and phosphatidylserine externalization, Caspase-Glo3/7 assays, DNA fragmentation gel, cyclophilin A release gel, PAMPA, and confocal imaging. Sulforhodamine B assays show that MAP-870 does indeed cause growth inhibition and cell death in the model tested. PAMPA assays show that MAP-870 does not …

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Regulation Of Sensory Neurogenesis In The Trigeminal Placode: Notch Pathway Genes, Pax3 Isoforms, And Wnt Ligands, Jason Samuel Adams Nov 2012

Regulation Of Sensory Neurogenesis In The Trigeminal Placode: Notch Pathway Genes, Pax3 Isoforms, And Wnt Ligands, Jason Samuel Adams

Theses and Dissertations

This dissertation is divided into three chapters, each discussing the study of different regulatory molecules involved in sensory neurogenesis occurring in the trigeminal placode. Chapter one is a spatiotemporal description of Notch pathway genes in chick opV placode by stage-specific expression analysis, showing expression of many Notch pathway genes and effectors in the opV placode. Notch pathway gene expression is primarily confined to the ectoderm with highest expression of these genes at the beginning stages of peak neuronal differentiation. This information preceded studies of the functional roles that Notch signaling has in the opV placode and how it may affect …

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Full Issue Nov 2012

Full Issue

Swiss American Historical Society Review

No abstract provided.

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Front Matter, Vol. 6 Nov 2012

Front Matter, Vol. 6

Monographs of the Western North American Naturalist

No abstract provided.

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The Ideas Of Jean Piaget: Using Theory To Better Understand Theory And Improve Learning, William E. Herman Nov 2012

The Ideas Of Jean Piaget: Using Theory To Better Understand Theory And Improve Learning, William E. Herman

Swiss American Historical Society Review

M ost readers will note the irony embedded in the title of this paper and the Einstein quote. There is an obvious and important thread of truth derived from such premises. Is it prudent and scholarly to employ Jean Piaget's theory in order to more deeply explore the meaning of Piaget's theory? Biblical scholars have long been known to use the writings of the Apostles and other Biblical voices as tools to understand sacred text. In this way, the Bible is used to understand the Bible. As the Swiss theologian Karl Barth once stated regarding the daring element of Christian …

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Functionalization Of In-Plane Photonic Microcantilever Arrays For Biosensing Applications, Stanley J. Ness Oct 2012

Functionalization Of In-Plane Photonic Microcantilever Arrays For Biosensing Applications, Stanley J. Ness

Theses and Dissertations

Microcantilevers have been investigated as high sensitivity, label free biosensors for approximately 15 years. In nearly all cases, a thin gold film deposited on the microcantilevers is used as an intermediate attachment layer because of the convenience of thiol-gold chemistry. Unfortunately, this attachment chemistry can be unstable when used with complex sample media such as blood plasma. The Nordin group at BYU has recently developed an all-silicon in-plane photonic microcantilever (PMCL) technology to serve as a platform for label-free biosensing. It has the advantage of being readily scalable to simultaneous readout of many PMCLs in array format, and allows integration …

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The Role Of Case-Hardening In The Development And Preservation Of Narrow, Vertical-Walled Canyons In Adršpach-Teplice, Czech Republic, Shawn Austin Wiggins Oct 2012

The Role Of Case-Hardening In The Development And Preservation Of Narrow, Vertical-Walled Canyons In Adršpach-Teplice, Czech Republic, Shawn Austin Wiggins

Theses and Dissertations

The geomorphology at Adršpach-Teplice, Czech Republic is dominated by vertical-walled, fracture-controlled features including slot canyons, gorges and pillars. Surfaces of canyon walls in Adršpach are case-hardened and more resistant to erosion than the bulk of the sandstone, which appears to be fundamental to the formation and preservation of canyons. Core and whole rock samples from Adršpach-Teplice were analyzed in thin section, including SEM analysis with cathodo luminescence. XRF and XRD analyses indicated that silica case-hardened surfaces are chemically and mineralogically similar to the rock interior, while iron case-hardened surfaces have an increase in iron present at the surface as the …

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Syngas Impurity Effects On Cell Growth, Enzymatic Activities And Ethanol Production Via Fermentation, Deshun Xu Oct 2012

Syngas Impurity Effects On Cell Growth, Enzymatic Activities And Ethanol Production Via Fermentation, Deshun Xu

Theses and Dissertations

A syngas compositional database with focus on trace impurities was established. For this work, ammonia (NH3) and benzene (C6H6) effects on cell growth, enzymatic activities of hydrogenase and alcohol dehydrogenase (ADH), and product formation were studied. NH3, after entering media, will be converted rapidly to NH4+, which will raise the total osmolarity of the media. NH3, as a common nutrient for the cell growth, is not the real culprit for cell growth inhibition. In essence, it is the high osmolarity resulting from the accumulation of NH4+ in the media which disrupts the normal regulation of the cells. It was concluded …

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Thermodynamic Kinetics And Efficiency Analysis Of Methyl Viologen, Chang Chen Oct 2012

Thermodynamic Kinetics And Efficiency Analysis Of Methyl Viologen, Chang Chen

Theses and Dissertations

Methyl Viologen (MV) is an electron mediator that has great possibilities to be used with an electrode system in which the electrode system provides electrons towards reducing MV species. MV has three redox states and they can be converted to each other via redox reactions on the surface of the electrode. The concentration of the three species of MV was related to the voltage potential applied to the system through a thermodynamic model. With the thermodynamic model the concentration of the three species can be predicted with different applied voltage potentials towards providing guidance for controlling the redox state of …

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Force Optimization And Flow Field Characterization From A Flapping Wing Mechanism, Nathaniel Stephen Naegle Oct 2012

Force Optimization And Flow Field Characterization From A Flapping Wing Mechanism, Nathaniel Stephen Naegle

Theses and Dissertations

Flapping flight shows promise for micro air vehicle design because flapping wings provide superior aerodynamic performance than that of fixed wings and rotors at low Reynolds numbers. In these flight regimes, unsteady effects become increasingly important. This thesis explores some of the unsteady effects that provide additional lift to flapping wings through an experiment-based optimization of the kinematics of a flapping wing mechanism in a water tunnel. The mechanism wings and flow environment were scaled to simulate the flight of the hawkmoth (Manduca sexta) at hovering or near-hovering speeds. The optimization was repeated using rigid and flexible wings …

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Full Issue, Comparative Civilizations Review Review Oct 2012

Full Issue, Comparative Civilizations Review Review

Comparative Civilizations Review

No abstract provided.

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