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A Hydrothermal After-Ripening Time Model For Seed Dormancy Loss In Bromus Tectorum L., Phil S. Allen, Necia B. Bair Mar 2006

A Hydrothermal After-Ripening Time Model For Seed Dormancy Loss In Bromus Tectorum L., Phil S. Allen, Necia B. Bair

Faculty Publications

After-ripening, the loss of dormancy under dry conditions, is associated with a decrease in mean base water potential for germination of Bromus tectorum L. seeds. After-ripening rate is a linear function of temperature above a base temperature, so that dormancy loss can be quantified using a thermal after-ripening time (TAR) model. To incorporate storage water potential into TAR, we created a hydrothermal after-ripening time (HTAR) model. Seeds from two B. tectorum populations were stored under controlled temperatures (20 or 30° C) and water potentials (400 to 40MPa). Subsamples were periodically removed from each storage treatment and incubated at 15 or …

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Measurement, Characterization, And Source Apportionment Of The Major Chemical Components Of Fine Particulate Material, Including Semi-Volatile Species, Brett D. Grover Feb 2006

Measurement, Characterization, And Source Apportionment Of The Major Chemical Components Of Fine Particulate Material, Including Semi-Volatile Species, Brett D. Grover

Theses and Dissertations

The promulgation of revised standards for atmospheric fine particles (PM2.5) by the US EPA has sparked renewed interest in the ability to accurately measure and characterize suspended atmospheric particulate matter. Semi-volatile material (SVM), consisting of ammonium nitrate and semi-volatile organic material (SVOM), is not accurately measured by EPA accepted methods such as the Federal reference method (FRM) or Tapered Element Oscillating Microbalance (TEOM). However, SVM is often a major fraction of urban aerosols. Recent advances in atmospheric sampling instrumentation allowed for the semi-continuous characterization of urban PM2.5, including SVM. The Filter Dynamic Measurement System (FDMS) was shown to measure total …

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Occurrence, Persistence, And Expansion Of Saltcedar (Tamarix Spp.) Populations In The Great Plains Of Montana, Jason P. Sexton, Anna Sala, Kevin Murray Feb 2006

Occurrence, Persistence, And Expansion Of Saltcedar (Tamarix Spp.) Populations In The Great Plains Of Montana, Jason P. Sexton, Anna Sala, Kevin Murray

Western North American Naturalist

Saltcedar (Tamarix spp.), a shrub native to Eurasia, is associated with major alterations to wetland and riparian systems in the southwestern United States. Since the 1960s saltcedar has been naturalized in northern states of the U.S. where its growth potential and impacts are not well known. Here, we describe the occurrence, age, size, and relative cover of saltcedar populations in several river basins in central eastern Montana, USA, to identify potential patterns of spread across the region and changes in individual populations as they age. Stands were aged according to the oldest saltcedar individuals and were sampled for dominant …

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Composition And Distribution Of The Milliped Tribe Pachydesmini West Of The Mississippi River (Polydesmida: Xystodesmidae), Rowland M. Shelley, Chris T. Mcallister Feb 2006

Composition And Distribution Of The Milliped Tribe Pachydesmini West Of The Mississippi River (Polydesmida: Xystodesmidae), Rowland M. Shelley, Chris T. Mcallister

Western North American Naturalist

The xystodesmid milliped tribe Pachydesmini is supported by the autapomorphic absence of bold aposematic pigmentations and possibly also by relative somatic inflexibility; it comprises 3 component genera: PachydesmusCook, 1895; Dicellarius Chamberlin, 1920; and Thrinaxoria Chamberlin and Hoffman, 1950. Three representatives occur west of the Mississippi River—P. clarus (Chamberlin), P. crassicutis crassicutis (Wood), and T. lampra (Chamberlin). New localities are documented in Louisiana and Texas, and literature records are summarized for these states and Arkansas; records of P. clarus from Cherokee County, Texas, are the westernmost in this state for the east-Nearctic xystodesmid fauna. An apparently allopatric population of …

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Behavioral And Physiological Responses Of Eared Grebes (Podiceps Nigricollis) To Variations In Brine Shrimp (Artemia Franciscana) Densities, Joe N. Caudell, Michael R. Conover Feb 2006

Behavioral And Physiological Responses Of Eared Grebes (Podiceps Nigricollis) To Variations In Brine Shrimp (Artemia Franciscana) Densities, Joe N. Caudell, Michael R. Conover

Western North American Naturalist

Eared Grebes (Podiceps nigricollis) use the Great Salt Lake (GSL) primarily as a fall staging area. They feed on brine shrimp (Artemia franciscana) to build up energy reserves to complete their southward migration. Whereas it has been speculated that timing of grebe departure from the GSL is due to declining shrimp density, this hypothesis has not been tested. We monitored grebe weight, behavior, and departure dates to test this hypothesis and to determine the effects of declining shrimp densities on Eared Grebes during 1999, 2000, and 2001 when there were different shrimp densities. Despite differences in …

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Community Response Of Nontarget Species To Herbicide Application And Removal Of The Nonindigenous Invader Potentilla Recta L., R. L. Sheley, M. Kirk Denny Feb 2006

Community Response Of Nontarget Species To Herbicide Application And Removal Of The Nonindigenous Invader Potentilla Recta L., R. L. Sheley, M. Kirk Denny

Western North American Naturalist

Our main objective was to improve understanding of herbicide effects on community dynamics to refine the use of technology and advance the development of ecologically based weed management strategies. We hypothesized that native grasslands would exhibit reductions in culturally sensitive forb cover, biomass, and density relative to the rate of application of selective rangeland herbicides, and that hand-removal of sulfur cinquefoil (Potentilla recta L.) would increase indigenous species cover, biomass, density, species richness, and diversity. Treatments consisted of 3 rates each of 2,4-D + clopyralid (0.28 kg ai · ha−1 + 0.0532 kg ai · ha−1, …

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Dietary Overlap In Giant Salamanders (Dicamptodon): Applying Null Models To Resource Partitioning, Craig A. Steele, Colin Brammer Feb 2006

Dietary Overlap In Giant Salamanders (Dicamptodon): Applying Null Models To Resource Partitioning, Craig A. Steele, Colin Brammer

Western North American Naturalist

We examined stomach contents of preserved specimens of larval Pacific giant salamander (Dicamptodon tenebrosus) and Cope's giant salamander (D. copei) collected from sympatric and allopatric stream populations. The dietary components of these specimens were used to calculate dietary overlap between the 2 species and to determine if changes in overlap existed between sympatric and allopatric populations. To statistically test overlap values, a randomization algorithm was used to construct a simulated data matrix (i.e., null model) in order to compare observed values of dietary overlap to a distribution of overlap values from the null model. Significant levels …

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Introducing The Dragonflies Of British Columbia And The Yukon By Robert A. Cannings, C. Riley Nelson Feb 2006

Introducing The Dragonflies Of British Columbia And The Yukon By Robert A. Cannings, C. Riley Nelson

Western North American Naturalist

No abstract provided.

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Band-Tailed Pigeon: Wilderness Bird At Risk By Worth Mathewson, Clayton M. White Feb 2006

Band-Tailed Pigeon: Wilderness Bird At Risk By Worth Mathewson, Clayton M. White

Western North American Naturalist

No abstract provided.

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Recovery And Germinability Of Native Seed Fed To Cattle, Marina K. Whitacre, Christopher A. Call Feb 2006

Recovery And Germinability Of Native Seed Fed To Cattle, Marina K. Whitacre, Christopher A. Call

Western North American Naturalist

Using livestock as seed dispersal agents may be an effective method for increasing species diversity on degraded and previously seeded rangelands. We quantified seed passage and recovery rates, and post-passage germinability of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young), bottlebrush squirreltail (Elymus elymoides [Raf.] Swezey), and gooseberry globemallow (Sphaeralcea grossulariaefolia [H. & A.] Rydb.) by feeding Holstein heifers seeds of each species at 3 levels (15,000; 30,000; and 60,000 seeds) over a period of 3 weeks. One-kg fecal samples were collected 1, 2, 3, and 4 days after seed ingestion. Undamaged seeds were …

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Aspects Of Sacramento Pikeminnow Biology In Nearshore Habitats Of The Sacramento–San Joaquin Delta, California, Matthew L. Nobriga, Frederick Feyrer, Randall D. Baxter Feb 2006

Aspects Of Sacramento Pikeminnow Biology In Nearshore Habitats Of The Sacramento–San Joaquin Delta, California, Matthew L. Nobriga, Frederick Feyrer, Randall D. Baxter

Western North American Naturalist

We documented distribution, relative abundance, diet composition, and body condition of Sacramento pikeminnow Ptychocheilus grandis during 2001 and 2003 at 5 sites in the Sacramento–San Joaquin Delta, California. Sacramento pikeminnow densities in nearshore habitats were higher in 2003 than 2001. In both years, spatial distribution of beach seine densities was similar. There were no significant differences in density among sampling sites except for the southernmost site where the catch was near zero. Based on rotary screw-trap data from a 6th site, we found relative abundance of Sacramento pikeminnow entering the Delta via an artificial floodplain was positively correlated with flow. …

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Transverse And Longitudinal Variation In Woody Riparian Vegetation Along A Montane River, Jonathan M. Friedman, Gregor T. Auble, Edmund D. Andrews, Gwen Kittel, Richard F. Madole, Eleanor R. Griffin, Tyler M. Allred Feb 2006

Transverse And Longitudinal Variation In Woody Riparian Vegetation Along A Montane River, Jonathan M. Friedman, Gregor T. Auble, Edmund D. Andrews, Gwen Kittel, Richard F. Madole, Eleanor R. Griffin, Tyler M. Allred

Western North American Naturalist

This study explores how the relationship between flow and riparian vegetation varies along a montane river. We mapped occurrence of woody riparian plant communities along 58 km of the San Miguel River in southwestern Colorado. We determined the recurrence interval of inundation for each plant community by combining step-backwater hydraulic modeling at 4 representative reaches with Log-Pearson analysis of 4 stream gaging stations. Finally, we mapped bottomland surficial geology and used a Geographic Information System to overlay the coverages of geology and vegetation. Plant communities were distinctly arrayed along the hydrologic gradient. The Salix exigua Nuttall (sandbar willow) community occurred …

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Long-Term Fire History In Great Basin Sagebrush Reconstructed From Macroscopic Charcoal In Spring Sediments, Newark Valley, Nevada, Scott Mensing, Stephanie Livingston, Pat Barker Feb 2006

Long-Term Fire History In Great Basin Sagebrush Reconstructed From Macroscopic Charcoal In Spring Sediments, Newark Valley, Nevada, Scott Mensing, Stephanie Livingston, Pat Barker

Western North American Naturalist

We use macroscopic charcoal analysis to reconstruct fire history in sagebrush (Artemisia tridentata var. wyomingensis and A. tridentata var. tridentata), in Newark Valley, Nevada. We analyzed charcoal at continuous 1-cm intervals (~7–127 years), and pollen at 2- to 10-cm intervals (~70–263 years) in a core spanning the last 5500 cal yr BP (calendar years before present). A charcoal peak in the historic period was associated with a >1400-ha fire dated to 1986 that burned in the watershed. We reconstructed the prehistoric fire history by inferring fires from similar charcoal peaks that were significantly greater than the background charcoal …

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Evaluating Plant Invasions From Both Habitat And Species Perspectives, Geneva W. Chong, Yuka Otsuki, Thomas J. Stohlgren, Debra Guenther, Paul Evangelista, Cynthia Villa, Alycia Waters Feb 2006

Evaluating Plant Invasions From Both Habitat And Species Perspectives, Geneva W. Chong, Yuka Otsuki, Thomas J. Stohlgren, Debra Guenther, Paul Evangelista, Cynthia Villa, Alycia Waters

Western North American Naturalist

We present an approach to quantitatively assess nonnative plant invasions at landscape scales from both habitat and species perspectives. Our case study included 34 nonnative species found in 142 plots (0.1 ha) in 14 vegetation types within the Grand Staircase–Escalante National Monument, Utah. A plot invasion index, based on nonnative species richness and cover, showed that only 16 of 142 plots were heavily invaded. A species invasive index, based on frequency, cover, and number of vegetation types invaded, showed that only 7 of 34 plant species were highly invasive. Multiple regressions using habitat characteristics (moisture index, elevation, soil P, native …

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Transborder Associations Of Terrestrial Isopods (Crustacea, Isopoda, Oniscidea) Of Mexico And The United States, Joan P. Jass, Barbara R. Klausmeier Feb 2006

Transborder Associations Of Terrestrial Isopods (Crustacea, Isopoda, Oniscidea) Of Mexico And The United States, Joan P. Jass, Barbara R. Klausmeier

Western North American Naturalist

No abstract provided.

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The Comet Assay To Determine The Mode Of Cell Death For The Ultrasonic Delivery Of Doxorubicin To Human Leukemia (Hl-60 Cells) From Pluronic P105 Micelles, Ghaleb A. Husseini, Kim L. O'Neill, William G. Pitt Feb 2006

The Comet Assay To Determine The Mode Of Cell Death For The Ultrasonic Delivery Of Doxorubicin To Human Leukemia (Hl-60 Cells) From Pluronic P105 Micelles, Ghaleb A. Husseini, Kim L. O'Neill, William G. Pitt

Faculty Publications

This notes examines the mode of cell death of HL-60 cells exposed to 70 kHz and 1.3 W/cm2 in the presence of 1% Pluronic P105 and 1.67 μg/ml doxorubicin (Dox). The cells were ultrasonicated for 30, 60 and 120 minutes. They were then lysed, electrophorised, stained using propidium iodide, and their DNA profile captured using a fluorescent microscope. The gradual DNA damage observed and the comet tails captured after 1 and 2 hours of insonation suggest that the mode of cell killing is apoptosis.

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Evolution Of The Nanog Pseudogene Family In The Human And Chimpanzee Genomes, Daniel J. Fairbanks, Peter J. Maughan Feb 2006

Evolution Of The Nanog Pseudogene Family In The Human And Chimpanzee Genomes, Daniel J. Fairbanks, Peter J. Maughan

Faculty Publications

The NANOG gene is expressed in mammalian embryonic stem cells where it maintains cellular pluripotency. An unusually large family of pseudogenes arose from it with one unprocessed and ten processed pseudogenes in the human genome. This article compares the NANOG gene and its pseudogenes in the human and chimpanzee genomes and derives an evolutionary history of this pseudogene family. Results: The NANOG gene and all pseudogenes except NANOGP8 are present at their expected orthologous chromosomal positions in the chimpanzee genome when compared to the human genome, indicating that their origins predate the human-chimpanzee divergence. Analysis of flanking DNA sequences demonstrates …

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Characterization, Functionalization And Applications Of Alkyl Monolayers On Silicon Surfaces, Guilin Jiang Feb 2006

Characterization, Functionalization And Applications Of Alkyl Monolayers On Silicon Surfaces, Guilin Jiang

Theses and Dissertations

Investigations were performed on the stability, mechanism of formation and an application of alkyl monolayers chemomechanically prepared on silicon surfaces. A new method of surface modification, laser-activation modification of surfaces (LAMS), and multivariate analyses of time-of-flight secondary ion mass spectrometry (ToF-SIMS) images of LAMS spots were also reported. X-ray photoelectron spectroscopy (XPS) and other data show that alkyl monolayers prepared by scribing silicon under 1-iodoalkanes and 1-alkenes were stable over extended periods of time to air, water, a boiling acid and Al Ka X-rays. The stability is attributed to direct Si-C bonding in the monolayers. The observation that the oxygen …

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Committee Activities, Hisami Konishi Springer, Anna U, Karen Wei Feb 2006

Committee Activities, Hisami Konishi Springer, Anna U, Karen Wei

Journal of East Asian Libraries

No abstract provided.

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The Book Of Mormon And Automatic Writing, Robert A. Rees Jan 2006

The Book Of Mormon And Automatic Writing, Robert A. Rees

Journal of Book of Mormon Studies

Some critics of the Book of Mormon have suggested that Joseph Smith produced the book through a process known as “automatic writing,” a rapid flow of language claimed to be generated through paranormal means such as trance-like states or claimed communications with spirits. This paper presents an overview of some prominent claims of automatic writing and examines the historical and scientific evidence for the authenticity of at least some of these cases. After discussing the similarities between these works and the Book of Mormon, the paper outlines a number of features in the Book of Mormon that clearly differentiate it …

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Journal Of Book Of Mormon Studies Volume 15 Issue 1, Neal A. Maxwell Institute For Religious Scholarship Jan 2006

Journal Of Book Of Mormon Studies Volume 15 Issue 1, Neal A. Maxwell Institute For Religious Scholarship

Journal of Book of Mormon Studies

The Journal of the Book of Mormon and Other Restoration Scripture is a peer-reviewed journal dedicated to promoting understanding of the history, meaning, and significance of the scriptures and other sacred texts revealed through the Prophet Joseph Smith.

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Remote Terrain Navigation For Unmanned Air Vehicles, Stephen R. Griffiths Jan 2006

Remote Terrain Navigation For Unmanned Air Vehicles, Stephen R. Griffiths

Theses and Dissertations

There are many applications for which small unmanned aerial vehicles (SUAVs) are well suited, including surveillance, reconnaissance, search and rescue, convoy support, and short-range low-altitude perimeter patrol missions. As technologies for microcontrollers and small sensors have improved, so have the capabilities of SUAVs. These improvements in SUAV performance increase the possibility for hazardous missions through mountainous and urban terrain in the successful completion of many of these missions. The focus of this research was on remote terrain navigation and the issues faced when dealing with limited onboard processing and limited payload and power capabilities. Additional challenges associated with canyon and …

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Fuel-Nox Formation During Low-Grade Fuel Combustion In A Swirling-Flow Burner, Chunyang Wu Jan 2006

Fuel-Nox Formation During Low-Grade Fuel Combustion In A Swirling-Flow Burner, Chunyang Wu

Theses and Dissertations

Insufficient knowledge of fireside behavior in the near-burner region during biomass combustion is one of major factors preventing widespread use of this renewable fuel in pulverized coal power plants. The current research is aimed to investigate the impact of biomass cofiring on NO formation in the near-burner region through interpretation of computational fluid dynamics (CFD) predictions and data collected from a series of biomass tests in a pilot-scale (0.2 MW), swirling flow burner. Two-dimensional gas species mole fraction data were collected with state-of-theart instruments from nine experiments, composing one herbaceous biomass (straw), one woody biomass (sawdust), a low sulfur sub-bituminous …

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Characterization Of The Role Of Sox9 In Cartilage-Specific Gene Regulation, Mary Ann Genzer Jan 2006

Characterization Of The Role Of Sox9 In Cartilage-Specific Gene Regulation, Mary Ann Genzer

Theses and Dissertations

Although advances have been made toward understanding the complex mechanisms that regulate the process of DNA transcription, the specific mechanisms of activation for many individual genes remain unknown. In this study, we focus on the role the transcription factor SOX9 plays in activating cartilage-specific genes, specifically Col9a1 and Cartilage Link Protein (CRTL1). Previously, enhancers of these genes containing single SOX9 binding sites were shown to be activated through SOX9 binding. However, the hypothesis was made that in cartilage-specific genes dimeric SOX9, as opposed to monomeric SOX9, is necessary for activation. We identified a putative binding site adjacent to each of …

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Editor's Introduction, Knowing Brother Joseph Again, Louis Midgley Jan 2006

Editor's Introduction, Knowing Brother Joseph Again, Louis Midgley

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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Addressing Questions Surrounding The Book Of Mormon And Dna Research, John M. Butler Jan 2006

Addressing Questions Surrounding The Book Of Mormon And Dna Research, John M. Butler

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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Dna And The Book Of Mormon, David G. Stewart Jr. Jan 2006

Dna And The Book Of Mormon, David G. Stewart Jr.

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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Creation By Evolution?, Frank B. Salisbury Jan 2006

Creation By Evolution?, Frank B. Salisbury

Review of Books on the Book of Mormon 1989–2011

Review of Trent D. Stephens, D. Jeffrey Meldrum, with Forrest B. Peterson. Evolution and Mormonism: A Quest for Understanding.

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Joseph Smith And “Interpretive Biography”, Larry E. Morris Jan 2006

Joseph Smith And “Interpretive Biography”, Larry E. Morris

Review of Books on the Book of Mormon 1989–2011

Review of Dan Vogel. Joseph Smith: The Making of a Prophet.

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Vol. 18 Num. 1 The Farms Review, Farms Review Jan 2006

Vol. 18 Num. 1 The Farms Review, Farms Review

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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