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1836, Byu Studies

BYU Studies

No abstract provided.

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Ecology, Culture, And Rationality: Toynbee And Diamond On The Growth And Collapse Of Civilizations, George Von-Der-Muhll

Comparative Civilizations Review

No abstract provided.

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Psoda: Better Tasting And Less Filling Than Paup, Hyrum Carroll, Mark J. Clement, Mark Ebbert, Quinn O. Snell

Faculty Publications

PSODA is an open-source phylogenetic search application that implements traditional parsimony and likelihood search techniques as well as advanced search algorithms. PSODA is compatible with PAUP and the search algorithms are competitive with those in PAUP. PSODA also adds a basic scripting language to the PAUP block, making it possible to easily create advanced meta-searches. Additionally, PSODA provides a user-friendly GUI with real-time graphing visualizations and phylogeny viewer, and a multiple sequence alignment algorithm PSODA is freely available from the PSODA web site: http://csl.cs.byu.edu/psoda.

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Psodascript: Applying Advanced Language Constructs To Open-Source Phylogenetic Search, Hyrum Carroll, Mark J. Clement, Jonathan Krein, Quinn O. Snell, Adam R. Teichert

Faculty Publications

Due to the immensity of phylogenetic tree space for large data sets, researches must rely on heuristic searches to infer reasonable phylogenies. By designing meta-searches which appropriately combine a variety of heuristics and parameter settings, researchers can significantly improve the performance of heuristic searches. Advanced language constructs in the open-source PSODA project—including variables, mathematical and logical expressions, conditional statements, and user-defined commands—give researchers a better framework for the exploration and exploitation of phylogenetic meta-search algorithms. PSODA’s approach to scripting meta-search algorithms is unique among open-source packages and addresses several limitations of other phylogenetic applications.

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Using Parsimony To Guide Maximum Likelihood Searches, Hyrum Carroll, Mark J. Clement, Timothy O'Connor, Quinn O. Snell, Kenneth Sundberg

Faculty Publications

The performance of maximum likelihood searches can be boosted by using the most parsimonious tree as a starting point for the search. The time spent in performing the parsimony search to find this starting tree is insignificant compared to the time spent in the maximum likelihood search, leading to an overall gain in search time. These parsimony boosted maximum likelihood searches lead to topologies with scores statisitically similar to the unboosted searches, but in less time.

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Livestock And Vegetation Responses To Rotational Grazing In Short-Grass Steppe, Justin D. Derner, Richard H. Hart

Western North American Naturalist

There is a paucity of information concerning livestock and vegetation responses to rotational grazing in short-grass steppe. We compared effects between 1995 and 2003 of time-controlled, short-duration rotational grazing against season-long continuous grazing, at a moderate stocking rate (1.95 ha · animal unit month⁻¹), on livestock gains and on foliar and basal cover in short-grass steppe. Livestock average daily gains, grazing-season gains, and beef production did not differ between grazing systems. We observed no relationship between precipitation (annual or growing-season) and average daily gain. In contrast, both grazing-season gains and beef production exhibited a significant curvilinear response to …

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Roadside Foraging By Kangaroo Rats In A Grazed Short-Grass Prairie Landscape, Paul Stapp, Mark D. Lindquist

Western North American Naturalist

We used live-trapping and foraging experiments to describe use of roadside vegetation by kangaroo rats (Dipodomys ordii) in short-grass prairie in Colorado, and to determine whether this species' perception of predation risk differed between roadside habitats, where predators were expected to be most active, and locations 120 m into adjacent grazed pastures. Giving-up densities (GUDs) were measured in paired seed trays placed beneath saltbush (Atriplex canescens) shrubs and in the open, 3 m from shrubs along transects in roadside and pasture locations. Trials were conducted on nights with a partial (1st-quarter), full, and new moon to …

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Desert Rodents Reduce Seedling Recruitment Of Salsola Paulsenii, William S. Longland

Western North American Naturalist

Heteromyid rodents in the deserts of North America have been shown to harvest large quantities of seeds of both native and introduced plants from soil seed banks, but rarely has the impact of this seed removal been demonstrated experimentally. I used a series of fenced plots (some of which excluded rodents) to demonstrate that heteromyids at a western Nevada study site can measurably reduce seed banks and subsequent seedling establishment of Salsola paulsenii, an introduced invasive weed that has become a significant problem over much of the desert Southwest. The frequency of S. paulsenii seedlings in both 2004 and …

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Seasonality And Fidelity In Roost Use Of The Mexican Free-Tailed Bat, Tadarida Brasiliensis, In An Urban Setting, Jeffrey A. Scales, Kenneth T. Wilkins

Western North American Naturalist

We studied 7 urban roosts occupied by Mexican free-tailed bats (Tadarida brasiliensis) in downtown Waco, Texas, from August 2001 to September 2002. We examined frequency of roost use, colony sizes, and roost fidelity in relation to gender. Use of roosts and colony sizes were highest in the fall and lowest in the winter, but fluctuated widely during the study. These roosts were not used by maternity colonies, and patterns of occupancy suggested that they served as stopover sites during migratory seasons. Individual bats exhibited high fidelity to discrete roosts included in the study. However, the bats commonly left …

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Polymorphic Indian Ricegrass Populations Result From Overlapping Waves Of Migration, T. A. Jones, M. G. Redinbaugh, S. R. Larson, Y. Zhang, B. D. Dow

Western North American Naturalist

Indian ricegrass (Achnatherum hymenoides [Roem. & Schult.] Barkworth) is a rangeland species native to western North America with populations that may exhibit distinct seed-size morphs borne on separate plants. These morphs are often associated with very different levels of seed dormancy. We compared RAPD profiles of the relatively infrequent and highly dormant jumbo seed morph to its more germinable small or large (non-jumbo) companion seed morphs collected from 9 sites where they were sympatric. Jumbo seed accessions from 9 additional sites that did not exhibit seed polymorphism were included to better sample this seed morph across the species' range. …

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The Influence Of Fallen Tree Timing On Spruce Beetle Brood Production, Elizabeth G. Hebertson, Michael J. Jenkins

Western North American Naturalist

This study compared brood production of the spruce beetle (Dendroctonus rufipennis Kirby [Coleoptera: Curculionidae, Scolytinae]) in downed host material felled during summer and spring seasons on the Wasatch Plateau in south central Utah. Thirty-three matched pairs of Engelmann spruce (Picea engelmannii Parry ex Engelm.) trees were selected for study in spring 1996. One tree of each pair was cut during August 1996 (summer-felled), and the other tree was cut in early April 1997 (spring-felled), so that trees would be colonized by spruce beetles of the same flight period. Brood adults were collected and counted from bark samples, which …

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Present Effects Of Past Wildfires On The Diets Of Stream Fish, Peter Koetsier, Quenton Tuckett, Joshua White

Western North American Naturalist

We investigated present indirect effects from a decade-old burn on the diets of stream fish. Based on soil instability and burn patterns from a 12–14-year-old wildfire complex, we separated 9 streams into 3 conditions: unburned, burned, and burned/scoured (i.e., experiencing a massive scour event 1 year post-burn). In the streams, we measured light levels and water temperatures, and we estimated fish density and biomass. We removed the digestive tracts from 9–15 rainbow trout (Oncorhynchus mykiss) from each stream and used a gravimetric procedure to analyze gut contents. Canopy cover development may dictate the composition of dietary items. Greater …

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Aquatic Vertebrate Assemblages Of The Upper Clear Creek Watershed, California, Larry R. Brown, Jason T. May

Western North American Naturalist

We sampled streams in the Upper Clear Creek Watershed in northwestern California in fall 2004 and fall 2005 to document assemblages of aquatic vertebrates and to provide resource managers with information on the importance of these assemblages in terms of regional biodiversity. We used single-pass backpack electrofishing to sample 15 sites in fall 2004 and the same 15 sites plus 4 new sites in fall 2005. We captured 10 fish taxa and 2 species of larval amphibians. Seven of the fish taxa were native species. Of the exotic species, only brook trout (Salvelinus fontinalis) occurred at more than …

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Peregrine Quest: From A Naturalist's Field Notebook By Clayton M. White, C. Riley Nelson

Western North American Naturalist

No abstract provided.

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Genetic Diversity And Low Reproductive Success In Isolated Populations Of Utah Juniper (Juniperus Osteosperma, Cupressaceae), Loreen Allphin, Amy F. Hunt, Val J. Anderson

Western North American Naturalist

Utah juniper (Juniperus osteosperma) has greatly expanded its historical range in the western United States. Management plans for the species have focused on curtailing its encroachment into sagebrush and grassland communities. These plans often include burning or other methods of elimination. These methods may result in subdivision or fragmentation of existing juniper stands. We initiated a study at Dugway Proving Ground, a U.S. Army facility, to examine the effects of fragmentation on the reproductive success of Utah juniper in isolated populations. We used enzyme electrophoresis to quantify genetic variability in isolated populations. We also determined population reproductive success …

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Black Bears (Ursus Americanus) Harvest Jeffrey Pine (Pinus Jeffreyi) Seeds From Tree Canopies, Kellie M. Kuhn, Stephen B. Vander Wall

Western North American Naturalist

We documented black bears (Ursus americanus) consuming the seeds of Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada from late August through September. Shells of pine seeds were the exclusive item in 20 of 27 scat samples collected in September and October and comprised >90% of the remaining 7 samples. Bears obtain seeds of Jeffrey pines by climbing trees, removing ripe, unopened cones from branches, dismantling cones on the ground, and consuming the seeds. Cone harvesting by bears can cause substantial damage to cone-bearing trees and might result in high predispersal mortality of seeds. In …

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Ecological Classification And Monitoring Model For The Wyoming Big Sagebrush Shrubsteppe Habitat Type Of Northeastern Wyoming, Lakhdar Benkobi, Daniel W. Uresk, R. Dennis Child

Western North American Naturalist

The purposes of this study were to develop a multivariate statistical model related to plant succession, to classify by seral stage, and to monitor succession in Wyoming big sagebrush shrubsteppe habitat (Artemisia tridentata ssp. wyomingensis / Agropyron smithii–Bouteloua gracilis) in Thunder Basin National Grassland, Wyoming. This model can be used by range and wildlife managers to evaluate management alternatives by assessing changes in plant species cover and composition within and between seral stages. Four ecological seral stages that represent early to late succession were quantitatively identified with an estimated 92% accuracy. Three key plant species provided the necessary …

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Changes In Kit Fox–Coyote–Prey Relationships In The Great Basin Desert, Utah, Wendy M. Arjo, Eric M. Gese, Tim J. Bennett, Adam J. Kozlowski

Western North American Naturalist

Variation in kit fox (Vulpes macrotis) population parameters can be influenced by vegetative cover and the distribution and abundance of other predator and prey species. Dramatic changes to Great Basin Desert habitats, which can potentially impact mammalian species, have occurred in some areas in Utah. We examined kit fox demographics and prey populations from 1999 to 2001 on Dugway Proving Ground (DPG), a U.S. Army facility in Utah, and compared some parameters to historical levels (1956–1958, 1966–1969). Adult survival rates were fairly consistent between 1999 and 2000 and between 1999 and 2001; however, survival was greater in 2001 …

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The New Mexico Whiptail, Cnemidophorus Neomexicanus (Squamata: Teiidae), In The Great Basin Of North Central Utah, George V. Oliver, John W. Wright

Western North American Naturalist

We report the discovery of established populations of Cnemidophorus neomexicanus in the Salt Lake City area. These are the 1st records of this species in Utah and in the Great Basin and are far from all other known populations of the species. We conclude that C. neomexicanus was introduced in the Salt Lake City area, perhaps within the last 30 years.

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Development Of The Characteristics Of Science Questionnaire (Csq): Assessing Student Knowledge Of The Utah State Secondary Science Core Intended Learning Outcome 6 On The Nature Of Science, Bradford N. Talbert

Theses and Dissertations

Teaching students about the nature of science is an important and necessary part of secondary science curricula. The Utah State Office of Education has provided specific guidelines called intended learning outcomes (ILOs) to teachers in the state. The ILOs are based on the national standards presented in the Project 2061 publications of the American Association for the Advancement of Science in 1990 and 1993. The ILOs are not tied to any one scientific discipline such as biology or chemistry, but are intended as global statements describing what scientists do and how scientific knowledge is gained. ILO 6 prescribes that students …

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Novel Perturbation Approach For The Structure Factor Of The Attractive Hard-Core Yukawa Fluid, Andrij Trokhymchuk, Roman Melnyk, Filip Moucka, Ivo Nezbeda

Faculty Publications

A novel perturbation approach for the structure factor S(k) of the Lennard-Jones-type Yukawa fluid with z=1.8 is presented. An approach is based on a new reference system, that is, the short-range Yukawa model with z0 > z=1.8. By choosing for the reference system the value z0=6, it is shown that (i) the proposed approach for S(k) performs much better than the traditional hard-sphere reference perturbation method does; (ii) the use of an approximate mean spherical (MSA) description of the reference structure factor provides the results for S(k) that are more accurate as those obtained from the direct MSA computations; and (iii) …

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Improving Neural Network Classification Training, Michael Edwin Rimer

Theses and Dissertations

The following work presents a new set of general methods for improving neural network accuracy on classification tasks, grouped under the label of classification-based methods. The central theme of these approaches is to provide problem representations and error functions that more directly improve classification accuracy than conventional learning and error functions. The CB1 algorithm attempts to maximize classification accuracy by selectively backpropagating error only on misclassified training patterns. CB2 incorporates a sliding error threshold to the CB1 algorithm, interpolating between the behavior of CB1 and standard error backpropagation as training progresses in order to avoid prematurely saturated network weights. CB3 …

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Differential Resource Allocation In Deer Mice Exposed To Sin Nombre Virus, Eric Wilson, Erin M. Lehmer, Christine A. Clay, Stephen St. Jeor, Denise M. Dearing

Faculty Publications

The resource allocation hypothesis predicts that reproductive activity suppresses immunocompetence; however, this has never been tested in an endemic disease system with free-ranging mammals. We tested the resource allocation hypothesis in wild deer mice (Peromyscus maniculatus) with natural exposure to Sin Nombre Virus (SNV). Immunocompetence was estimated from the extent of swelling elicited after deer mice were injected with phytohemagglutinin (PHA); swelling is positively correlated with immunocompetence. After livetrapping deer mice, we determined their reproductive state and SNV infection status. Males were more likely to be seropositive for SNV than females (37% vs. 25%) and exhibited 10% less swelling after …

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Mothers: Heroes, Then And Now, Lauren Ellison

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

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Provincial Development In China: Lessons From Eu Regional Policy Experience, Phillip J. Bryson, Keren Sun

Faculty Publications

Regional development in the Chinese provinces and in the regions of the EU countries are evaluated and compared. Development efforts in southern Italy, northeast England and eastern Germany are reviewed along with EU, Community-wide regional development programs. Equity concerns suggest promotion of regional policy, but the pursuit of maximum national economic growth would avoid it, since it sacrifices some economic growth. The impact of FDI and domestic investments on individual Chinese provinces is compared with their impact in Europe. There is an implicit contrast between public sector regional development programs and more effective private foreign direct investments.

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Optimization Of Control Source And Error Sensor Locations In Free Field Active Noise Control, Connor Raymond Duke

Theses and Dissertations

Previous work has shown that active noise control (ANC) can be applied to axial cooling fans. Optimization of the control source and error sensor placement is desired to maximize the attenuation using ANC. A genetic algorithm was developed to find the optimal placement of control sources for a given primary source. The optimal configuration of control sources around a single primary source was shown to be a linear arrangement of the sources. This holds true for both two-dimensional as well as three-dimensional configurations. The higher-order radiation of the linear arrangement has also been verified experimentally, but the improvement in the …

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Testing The Assumption Of Sample Invariance Of Item Difficulty Parameters In The Rasch Rating Scale Model, Joseph A. Curtin

Theses and Dissertations

Rasch is a mathematical model that allows researchers to compare data that measure a unidimensional trait or ability (Bond & Fox, 2007). When data fit the Rasch model, it is mathematically proven that the item difficulty estimates are independent of the sample of respondents. The purpose of this study was to test the robustness of the Rasch model with regards to its ability to maintain invariant item difficulty estimates when real (data that does not perfectly fit the Rasch model), polytomous scored data is used. The data used in this study comes from a university alumni questionnaire that was collected …

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Design And Fabrication Of Out-Of-Plane Silicon Microneedles With Integrated Hydrophobic Microchannels, Michael S. Diehl

Theses and Dissertations

Microfabricated needles have the potential for inexpensive drug delivery without pain. The ability to deliver medication painlessly to patients will someday be not just hoped for but expected by the general public. The commercialization of this technology will also lead to other valuable technologies, such as systems that continually monitor and control insulin or other drugs in diabetic patients. This research presents fabrication procedures developed to produce pyramidal-shaped microneedles with microchannels that will allow for fluid delivery. The microchannels are etched into the substrate surface of a [100] silicon wafer using inductively coupled plasma etching. After the channel etch a …

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Differential Response Of Various Spore Species To Sporicidal Disinfectants, Michael David Pratt

Theses and Dissertations

In the fall of 2001, letters laced with anthrax spores were delivered to various news organizations in New York and Florida, as well as to two Senators in Washington, D.C. Over 22 anthrax infections and five deaths resulted from exposure to these spores, and decontamination of the affected buildings was both time consuming and costly. Since these attacks, interest in sporicidal disinfectants has increased greatly. Many chemical sporicidal disinfectants are available commercially, but the exposure time required to sterilize can be relatively long. In addition, some spores are simply injured or inhibited by chemical disinfectants, but not necessarily killed. Studies …

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An Adaptive Bayesian Approach To Bernoulli-Response Clinical Trials, Andrew W. Stacey

Theses and Dissertations

Traditional clinical trials have been inefficient in their methods of dose finding and dose allocation. In this paper a four-parameter logistic equation is used to model the outcome of Bernoulli-response clinical trials. A Bayesian adaptive design is used to fit the logistic equation to the dose-response curve of Phase II and Phase III clinical trials. Because of inherent restrictions in the logistic model, symmetric candidate densities cannot be used, thereby creating asymmetric jumping rules inside the Markov chain Monte Carlo algorithm. An order restricted Metropolis-Hastings algorithm is implemented to account for these limitations. Modeling clinical trials in a Bayesian framework …

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Full-Text Articles in Entire DC Network

1836, Byu Studies

BYU Studies

Ecology, Culture, And Rationality: Toynbee And Diamond On The Growth And Collapse Of Civilizations, George Von-Der-Muhll

Comparative Civilizations Review

Psoda: Better Tasting And Less Filling Than Paup, Hyrum Carroll, Mark J. Clement, Mark Ebbert, Quinn O. Snell

Faculty Publications

Psodascript: Applying Advanced Language Constructs To Open-Source Phylogenetic Search, Hyrum Carroll, Mark J. Clement, Jonathan Krein, Quinn O. Snell, Adam R. Teichert

Faculty Publications

Using Parsimony To Guide Maximum Likelihood Searches, Hyrum Carroll, Mark J. Clement, Timothy O'Connor, Quinn O. Snell, Kenneth Sundberg

Faculty Publications

Livestock And Vegetation Responses To Rotational Grazing In Short-Grass Steppe, Justin D. Derner, Richard H. Hart

Western North American Naturalist

Roadside Foraging By Kangaroo Rats In A Grazed Short-Grass Prairie Landscape, Paul Stapp, Mark D. Lindquist

Western North American Naturalist

Desert Rodents Reduce Seedling Recruitment Of Salsola Paulsenii, William S. Longland

Western North American Naturalist

Seasonality And Fidelity In Roost Use Of The Mexican Free-Tailed Bat, Tadarida Brasiliensis, In An Urban Setting, Jeffrey A. Scales, Kenneth T. Wilkins

Western North American Naturalist

Polymorphic Indian Ricegrass Populations Result From Overlapping Waves Of Migration, T. A. Jones, M. G. Redinbaugh, S. R. Larson, Y. Zhang, B. D. Dow

Western North American Naturalist

The Influence Of Fallen Tree Timing On Spruce Beetle Brood Production, Elizabeth G. Hebertson, Michael J. Jenkins

Western North American Naturalist

Present Effects Of Past Wildfires On The Diets Of Stream Fish, Peter Koetsier, Quenton Tuckett, Joshua White

Western North American Naturalist

Aquatic Vertebrate Assemblages Of The Upper Clear Creek Watershed, California, Larry R. Brown, Jason T. May

Western North American Naturalist

Peregrine Quest: From A Naturalist's Field Notebook By Clayton M. White, C. Riley Nelson

Western North American Naturalist

Genetic Diversity And Low Reproductive Success In Isolated Populations Of Utah Juniper (Juniperus Osteosperma, Cupressaceae), Loreen Allphin, Amy F. Hunt, Val J. Anderson

Western North American Naturalist

Black Bears (Ursus Americanus) Harvest Jeffrey Pine (Pinus Jeffreyi) Seeds From Tree Canopies, Kellie M. Kuhn, Stephen B. Vander Wall

Western North American Naturalist

Ecological Classification And Monitoring Model For The Wyoming Big Sagebrush Shrubsteppe Habitat Type Of Northeastern Wyoming, Lakhdar Benkobi, Daniel W. Uresk, R. Dennis Child

Western North American Naturalist

Changes In Kit Fox–Coyote–Prey Relationships In The Great Basin Desert, Utah, Wendy M. Arjo, Eric M. Gese, Tim J. Bennett, Adam J. Kozlowski

Western North American Naturalist

The New Mexico Whiptail, Cnemidophorus Neomexicanus (Squamata: Teiidae), In The Great Basin Of North Central Utah, George V. Oliver, John W. Wright

Western North American Naturalist

Development Of The Characteristics Of Science Questionnaire (Csq): Assessing Student Knowledge Of The Utah State Secondary Science Core Intended Learning Outcome 6 On The Nature Of Science, Bradford N. Talbert

Theses and Dissertations

Novel Perturbation Approach For The Structure Factor Of The Attractive Hard-Core Yukawa Fluid, Andrij Trokhymchuk, Roman Melnyk, Filip Moucka, Ivo Nezbeda

Faculty Publications

Improving Neural Network Classification Training, Michael Edwin Rimer

Theses and Dissertations

Differential Resource Allocation In Deer Mice Exposed To Sin Nombre Virus, Eric Wilson, Erin M. Lehmer, Christine A. Clay, Stephen St. Jeor, Denise M. Dearing

Faculty Publications

Mothers: Heroes, Then And Now, Lauren Ellison

Religious Educator: Perspectives on the Restored Gospel

Provincial Development In China: Lessons From Eu Regional Policy Experience, Phillip J. Bryson, Keren Sun

Faculty Publications

Optimization Of Control Source And Error Sensor Locations In Free Field Active Noise Control, Connor Raymond Duke

Theses and Dissertations

Testing The Assumption Of Sample Invariance Of Item Difficulty Parameters In The Rasch Rating Scale Model, Joseph A. Curtin

Theses and Dissertations

Design And Fabrication Of Out-Of-Plane Silicon Microneedles With Integrated Hydrophobic Microchannels, Michael S. Diehl

Theses and Dissertations

Differential Response Of Various Spore Species To Sporicidal Disinfectants, Michael David Pratt

Theses and Dissertations

An Adaptive Bayesian Approach To Bernoulli-Response Clinical Trials, Andrew W. Stacey

Theses and Dissertations