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Mining Patterns Of The Aspen Leaf Miner, Phyllocnistis Populiella, On Its Host Plant, Populus Tremuloides, Martin L. Morton, Maria E. Pereyra Apr 2011

Mining Patterns Of The Aspen Leaf Miner, Phyllocnistis Populiella, On Its Host Plant, Populus Tremuloides, Martin L. Morton, Maria E. Pereyra

Western North American Naturalist

Feeding behavior of aspen leaf miner (Phyllocnistis populiella) larvae on quaking aspen (Populus tremuloides) leaves was examined, by using image-analysis software, to determine the pattern and distance of the larvae’s mining trails and measure the surface area of infested leaves and consumed leaf tissue. Mining pathways between hatching and pupation sites were serpentine and generally followed predictable, sequential changes in orientation. This pattern was most obvious in smaller leaves, those with a surface area of about 700 mm2 or less. In leaves larger than 700 mm2, plasticity in mining behavior increased. The serpentine …


Spatial Organization Of Northern Flying Squirrels, Glaucomys Sabrinus: Territoriality In Females?, Jaya R. Smith, Dirk H. Van Vuren, Douglas A. Kelt, Michael L. Johnson Apr 2011

Spatial Organization Of Northern Flying Squirrels, Glaucomys Sabrinus: Territoriality In Females?, Jaya R. Smith, Dirk H. Van Vuren, Douglas A. Kelt, Michael L. Johnson

Western North American Naturalist

We determined home-range overlap among northern flying squirrels (Glaucomys sabrinus) to assess their spatial organization. We found extensive home-range overlap among females, and though this overlap could reflect social behavior, we found no evidence of attraction among females, with only one instance of den-sharing. Instead, our results suggest that females share foraging areas but may be territorial in portions of the home range, especially around den trees and during young-rearing. Home-range overlap could also result from the extrinsic effect of forest fragmentation due to timber harvest, which might impede dispersal and force squirrels to cluster on remaining fragments …


Breeding And Parental Care In The Endangered Tehuantepec Jackrabbit (Lepus Flavigularis), Tamara Rioja, Consuelo Lorenzo, Eduardo Naranjo, Laura Scott, Arturo Carrillo-Reyes Apr 2011

Breeding And Parental Care In The Endangered Tehuantepec Jackrabbit (Lepus Flavigularis), Tamara Rioja, Consuelo Lorenzo, Eduardo Naranjo, Laura Scott, Arturo Carrillo-Reyes

Western North American Naturalist

We documented date and duration of each breeding phase, breeding rate, nursing behavior, parental care, and leveret survival of the Tehuantepec jackrabbit (Lepus flavigularis), a critically endangered lagomorph. Between June 2006 and May 2008, we observed 60 adult radio-collared jackrabbits in Oaxaca, México. Tehuantepec jackrabbits exhibit breeding behaviors 250 days out of the year, with a high-intensity period during the rainy season (May–October). Females give birth to 2 leverets 32 days after copulation. Directly after birth, leverets are put into “beds” or “nests,” which are depressions in the ground covered by prairie grass (Jouvea pilosa). Females …


The Ploidy Races Of Atriplex Confertifolia (Chenopodiaceae), Stewart C. Sanderson Apr 2011

The Ploidy Races Of Atriplex Confertifolia (Chenopodiaceae), Stewart C. Sanderson

Western North American Naturalist

Previous accounts of polyploidy in the North American salt desert shrub Atriplex confertifolia (shadscale) have dealt with the distribution of polyploidy and the morphological and secondary chemical differences between races. The present study amplifies these studies and reveals additional ploidy-flavonoid races, with ploidy levels known to extend from 2x to 12x, and all except 2x and 12x represented by races with and without 6-methoxylation of flavonol compounds. Results of this study show that diploids across their range have about 113% as much DNA per genome as do polyploids and that parallel variation in monoploid genome size between diploids and accompanying …


Genetic Variation In Ecophysiological And Survival Responses To Drought In Two Native Grasses: Koeleria Macrantha And Elymus Elymoides, Huarong Zhang, Laura E. Dewald, Thomas E. Kolb, Dan F. Koepke Apr 2011

Genetic Variation In Ecophysiological And Survival Responses To Drought In Two Native Grasses: Koeleria Macrantha And Elymus Elymoides, Huarong Zhang, Laura E. Dewald, Thomas E. Kolb, Dan F. Koepke

Western North American Naturalist

Genetic variation in ecophysiological and survival responses to drought was studied in 2 northern Arizona native grass species, Koeleria macrantha (Ledeb.) Schult. (prairie Junegrass) and Elymus elymoides (Raf.) Swezey. ssp. elymoides (squirreltail). Low- and high-elevation populations of each species were compared in a greenhouse common garden experiment that included simulated drought. Leaf gas-exchange characteristics were significantly affected by simulated drought and often by population elevation, but gas-exchange responses to drought were similar for high- and low-elevation populations. Compared to high-elevation populations, low-elevation populations of both species had higher net photosynthetic rate and predawn water potential, and for E. elymoides had …


Melanism In Endangered Mohave Tui Chub Siphateles Bicolor Mohavensis Snyder 1918 (Cypriniformes: Cyprinidae), Sujan M. Henkanaththegedara, Craig A. Stockwell Apr 2011

Melanism In Endangered Mohave Tui Chub Siphateles Bicolor Mohavensis Snyder 1918 (Cypriniformes: Cyprinidae), Sujan M. Henkanaththegedara, Craig A. Stockwell

Western North American Naturalist

Although melanism has been reported in a wide variety of taxa, the presence of melanic individuals is relatively rare in fishes. Melanism in Mohave tui chub (Siphateles bicolor mohavensis), an endangered endemic of the Mojave Desert in California, is reported from 2 of 4 surveyed populations. The typical body color varies from dark brown to olive brown dorsally and is whitish ventrally; sides are silvery or golden, and fins are pale yellow to dusky red. While conducting population censuses in 2007–2008, we found 4 melanic Mohave tui chubs from 2 of 4 surveyed habitats. Two of 1049 fish …


The Relationships Among Plant Cover, Density, Seed Rain, And Dispersal Of Bromus Tectorum In High-Elevation Populations, Andrew R. Kanarek, Rebecca Hufft Kao Apr 2011

The Relationships Among Plant Cover, Density, Seed Rain, And Dispersal Of Bromus Tectorum In High-Elevation Populations, Andrew R. Kanarek, Rebecca Hufft Kao

Western North American Naturalist

The invasive species Bromus tectorum L. is recognized as one of the most ecologically and economically devastating weeds in the western United States. Although B. tectorumhas been studied extensively, few studies have examined its dispersal and spread. We collected data from sites with B. tectorum in and around Rocky Mountain National Park to quantify the relationships between plant cover/density and seed rain and dispersal distance. Results suggest that there is a positive relationship between density within a patch and local seed rain and that B. tectorum exhibits relatively limited short-distance dispersal (where seeds fell in close proximity to plants …


Information Support For Regional Water Resource Management In Ukraine, Yevgen Makarovskiy Apr 2011

Information Support For Regional Water Resource Management In Ukraine, Yevgen Makarovskiy

Open Water Journal

Water resources availability is a determining factor of human existence. Despite the huge volume of water in the hydrosphere, water resources include only those waters that may be used by humans for drinking and household water supply and those ones that support the sustainable existence of living ecosystems.

The issues of drinking water consumption are particularly important. Only fresh surface water and groundwater, complied with quality standards, may be used for drinking water supply.

At the same time, precisely surface waters are under influence of anthropogenic load primarily due to their depletion and chemical and biological pollution. In some cases, …


An Approach Toward The Existing Challenges In Integrated (Fresh) Water Resources Management (Iwrm) And Presentation Of Strategies, M. Shafghati, A. Salajeghe Apr 2011

An Approach Toward The Existing Challenges In Integrated (Fresh) Water Resources Management (Iwrm) And Presentation Of Strategies, M. Shafghati, A. Salajeghe

Open Water Journal

Previously, because of low population, water crisis was not too tangible like these days so currently the given crisis has been exacerbated more than ever by rising growth of population. Gradually by increasing demand for water, the requirement for supply and development of water sources, thus developing state- of- art technologies will be increased in order to restore and expand fresh water sources, as well.

With respect to this fact that water is considered as the main factor for life and cultivation, but UN has proposed this decade as water scarcity decennium (2005-2015) and a global concern so this problem …


Environmental Implications Of Polymer Coated Urea, Joshua James Lemonte Apr 2011

Environmental Implications Of Polymer Coated Urea, Joshua James Lemonte

Theses and Dissertations

Nitrogen is an essential plant nutrient in the biosphere. Although N is necessary and beneficial for life, it is also a common pollutant in the atmosphere and hydrosphere as it may be lost to the atmosphere as ammonia (NH3) or nitrous oxide (N2O) gases or to groundwater as nitrate (NO3-) following fertilization. Polymer coated urea (PCU) is one type of N fertilizer which uses temperature-controlled diffusion to control N release to better match plant demand and mitigate environmental losses of N. The objectives of this project were to simultaneously compare the effects of PCU on gaseous (as N2O and NH3) …


Nanocomposite High Displacement Strain Gauges For Use In Human-Machine Interfaces: Applications In Hand Pose Determination, Thomas B. Calkins Apr 2011

Nanocomposite High Displacement Strain Gauges For Use In Human-Machine Interfaces: Applications In Hand Pose Determination, Thomas B. Calkins

Theses and Dissertations

Conductive nanocomposites are finding many uses as multi-functional materials. One recent development involves the creation of high displacement strain gauges, which have potential applications in a variety of engineering roles. The piezoresistive nature of the gauges makes possible their strain sensing capability. The intent of this research is to show that specific High Displacement Strain Gauges can successfully be used in one human-machine interface application that will demonstrate their potential for a range of other human-machine interface applications. This will be shown in the development of these sensors to accomplish hand pose determination. The flexible and inexpensive gauges are attached …


Modeling, Design, And Testing Of An Underwater Microactuation System Using A Standard Mems Foundry Process, Gregory L. Holst Apr 2011

Modeling, Design, And Testing Of An Underwater Microactuation System Using A Standard Mems Foundry Process, Gregory L. Holst

Theses and Dissertations

This work presents the modeling, design, and testing of an underwater microactuation system. It is composed of several thermomechanical in-plane microactuators (TIM) integrated with a ratchet system to provide long displacements and high forces to underwater microelectromechanical systems (MEMS). It is capable of actuating a 200µN load 110µm. It is a two-layer silicon MEMS device fabricated with a MEMS fabrication process, PolyMUMPS. This work also shows the development of an elliptic integral model to analyze the compliant fixed-guided beams in the TIM and gives new insight into the buckling behavior, reaction forces, and displacement of the beams. The derivation, verification, …


Longitudinal Changes In The Corpus Callosum Following Pediatric Traumatic Brain Injury As Assessed By Volumetric Mri And Diffusion Tensor Imaging, Trevor Chuang Kuo Wu Apr 2011

Longitudinal Changes In The Corpus Callosum Following Pediatric Traumatic Brain Injury As Assessed By Volumetric Mri And Diffusion Tensor Imaging, Trevor Chuang Kuo Wu

Theses and Dissertations

Atrophy of the corpus callosum (CC) is a documented consequence of moderate-to-severe traumatic brain injury (TBI), which has been expressed as volume loss using quantitative magnetic resonance imaging (MRI). Other advanced imaging modalities such as diffusion tensor imaging (DTI) have also detected white matter microstructural alteration following TBI in the CC. The manner and degree to which macrostructural changes such as volume and microstructural changes develop over time following pediatric TBI and their relation to a measure of processing speed is the focus of this longitudinal investigation. As such, DTI and volumetric changes of the CC in participants with TBI …


Morphological Convergence During Pregnancy Among Predator And Nonpredator Populations Of The Livebearing Fish Brachyrhaphis Rhabdophora (Teleostei: Poeciliidae), Jeff S. Wesner, Eric J. Billman, Adam Meier, Mark C. Belk Apr 2011

Morphological Convergence During Pregnancy Among Predator And Nonpredator Populations Of The Livebearing Fish Brachyrhaphis Rhabdophora (Teleostei: Poeciliidae), Jeff S. Wesner, Eric J. Billman, Adam Meier, Mark C. Belk

Faculty Publications

Predation can drive morphological divergence in prey populations, although examples of divergent selection are typically limited to nonreproductive individuals. In livebearing females, shape often changes drastically during pregnancy, reducing speed and mobility and enhancing susceptibility to predation. In the present study, we document morphological divergence among populations of nonreproductive female livebearing fish (Brachyrhaphis rhabdophora) in predator and nonpredator environments. We then test the hypothesis that shape differences among nonreproductive females are maintained among reproductive females between predator and nonpredator environments. Nonreproductive females in predator environments had larger caudal regions and more fusiform bodies than females in nonpredator environments; …


The Divine Nature And Destiny Of Women, Glenn L. Pace Apr 2011

The Divine Nature And Destiny Of Women, Glenn L. Pace

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Becoming Master Teachers, Joseph Fielding Mcconkie, Richard Neitzel Holzapfel Apr 2011

Becoming Master Teachers, Joseph Fielding Mcconkie, Richard Neitzel Holzapfel

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Vol. 12 No. 1 Religious Educator, Religious Educator Apr 2011

Vol. 12 No. 1 Religious Educator, Religious Educator

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Aligning Instructional Practices With Content Standards In Junior Secondary Schools In Indonesia, Rumtini Suwarno Mar 2011

Aligning Instructional Practices With Content Standards In Junior Secondary Schools In Indonesia, Rumtini Suwarno

Theses and Dissertations

This study examined the degree of alignment between instructional practices and national curriculum standards, which may vary as a function of teacher characteristics. Using self-reports from teachers about their experiences teaching the national curriculum standards, the study explored three aspects of the alignments: (1) topic coverage, (2) level of difficulty for teachers to teach, and (3) level of difficulty for students to learn. While topic coverage is determined by the percentage of the national curriculum standards topics taught during the year of 2008-2009, the level of teacher difficulty to teach and the level of student difficulty to learn are assessed …


Predicting Phenotypic Severity Of Uncertain Gene Variants In The Ret Proto-Oncogene, David K. Crockett, Stephen R. Piccolo, Perry G. Ridge, Rebecca L. Margraf, Elaine Lyon, Marc S. Williams, Joyce A. Mitchell Mar 2011

Predicting Phenotypic Severity Of Uncertain Gene Variants In The Ret Proto-Oncogene, David K. Crockett, Stephen R. Piccolo, Perry G. Ridge, Rebecca L. Margraf, Elaine Lyon, Marc S. Williams, Joyce A. Mitchell

Faculty Publications

Although reported gene variants in the RET oncogene have been directly associated with multiple endocrine neoplasia type 2 and hereditary medullary thyroid carcinoma, other mutations are classified as variants of uncertain significance (VUS) until the associated clinical phenotype is made clear. Currently, some 46 non-synonymous VUS entries exist in curated archives. In the absence of a gold standard method for predicting phenotype outcomes, this follow up study applies feature selected amino acid physical and chemical properties feeding a Bayes classifier to predict disease association of uncertain gene variants into categories of benign and pathogenic. Algorithm performance and VUS predictions were …


Kin Care And Perceptions Of Equity Among Ugandan Youth, Laurel George, Jini Roby Mar 2011

Kin Care And Perceptions Of Equity Among Ugandan Youth, Laurel George, Jini Roby

FHSS Mentored Research Conference

Children receiving kin care in Sub-Saharan Africa are at risk for differential treatment, especially where household resources are scarce. Using Pearson χ2 and multinomial logistic regression, we investigated whether such disparity exists within households receiving agency oversight and services designed to protect such children and preserve family households. We use existing data from face-to-face interviews with Ugandan youth age 8 to 18 (N = 518) and their caregivers to examine whether differences exist in child-perceived equity of food distribution and work requirements by type of family relatedness to caregiver. Income, but not relatedness, was negatively associated with food inequity, but …


Examining Predictors Of Optimism In Adolescence: Internal And External Factors, E Chrissy Bulloch Mar 2011

Examining Predictors Of Optimism In Adolescence: Internal And External Factors, E Chrissy Bulloch

Theses and Dissertations

This study examined the relationship between parenting, adolescent personality, and adolescent optimism. Four hundred and eighty families with at least one adolescent child in the Seattle, Washington area completed a series of questionnaires assessing parenting style, personality, and optimism. Results from hierarchical regression analyses indicated that there is a small, yet significant, portion of the variance in optimism explained by parenting and personality individually, but that the relationship between optimism, parenting, and personality dynamics is far more complex than originally anticipated. Further research is needed to examine the nature of these relationships and to provide a more comprehensive understanding of …


Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu Mar 2011

Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu

Theses and Dissertations

Microcantilever arrays have been shown to be promising label-free nanomechanical sensing devices with high sensitivity. Two factors that affect the usefulness of microcantilevers in sensing scenarios are the sensitivity of the transduction method for measuring changes in microcantilever properties and the ability to create large compact arrays of microcantilevers. In this dissertation, we demonstrate that microcantilevers with an in-plane photonic transduction method are attractive because they maintain the sensitivity of the traditional laser beam reflection method while being scalable to simultaneous readout of large microcantilever arrays. First I demonstrate the integration of a compact waveguide splitter network with in-plane photonic …


Association Between Academic Performance And Electrocortical Processing Of Cognitive Stimuli In College Students, Mary Menn Wolf Mar 2011

Association Between Academic Performance And Electrocortical Processing Of Cognitive Stimuli In College Students, Mary Menn Wolf

Theses and Dissertations

Because event-related potentials (ERPs) can reflect individual differences in intellectual ability, individual differences in college grade-point average (GPA) may be associated with specific individual ERP waves, such as the P300. However, P300 amplitude is higher in women than in men and varies across the menstrual cycle, factors that could confound the association between GPA and ERPs. In this regard, our objective was to determine whether differences in GPA are reflected in ERPs while standardling for sex and menstrual phase. After participants provided informed consent, we obtained GPAs from 22 right-handed college students (11 male, age range 22 to 26 and …


De Novo Genome Assembly And Snp Marker Development Of Pyrenophora Semeniperda, Marcus Makina Soliai Mar 2011

De Novo Genome Assembly And Snp Marker Development Of Pyrenophora Semeniperda, Marcus Makina Soliai

Theses and Dissertations

Pyrenophora semeniperda (anamorph Drechslera campulata) is a necrotrophic fungal seed pathogen of a variety of grass genra and species, including Bromus tectorum, an exotic grass that has invaded many natural ecosystems of the U.S. Intermountain West. As a natural seed pathogen of B. tectorum, P. semeniperda has potential as a biocontrol agent due to its effectiveness at killing dormant B. tectorum seeds; however, few genetic resources exist for this fungus. Here, the genome assembly of a P. semeniperda isolate using 454 GS-FLX genomic and paired-end pyrosequencing techniques is presented. The total assembly is 32.5 Mb and contains …


Usage And Development Of Molecular Markers For Investigation Of The Population And Ecological Genetics Of Bromus Tectorum L., Keith R. Merrill Mar 2011

Usage And Development Of Molecular Markers For Investigation Of The Population And Ecological Genetics Of Bromus Tectorum L., Keith R. Merrill

Theses and Dissertations

This thesis includes two studies: The first examined patterns of neutral genetic diversity within Bromus tectorum L. across the IMW region, and uses patterns of microsatellite (SSR) genotype distribution to make inferences about the respective roles of adaptively significant genetic variation, adaptive phenotypic plasticity, and facultative outcrossing in the ongoing invasion and recent range expansion of B. tectorum. It has been previously demonstrated that, due to extremely low outcrossing rates, it is possible to characterize individual genotypes of this species using four SSR loci. We sampled 20 individuals from each of 96 B. tectorum populations (classified by region and …


Apparent Competition With Bromus Tectorum Through Pyrenophora Semeniperda Reduces Establishment Of Native Grasses, Katherine Temus Merrill Mar 2011

Apparent Competition With Bromus Tectorum Through Pyrenophora Semeniperda Reduces Establishment Of Native Grasses, Katherine Temus Merrill

Theses and Dissertations

Contributing to the success of Bromus tectorum in the Intermountain West may be a mechanism called apparent competition, which occurs when one species increases the pressure of a consumer on a second species. This indirect interaction has been documented only a few times in invasive plant systems, and never in a fungal pathosystem. We examined the effects of the invasive annual Bromus tectorum and predation by the seed pathogen Pyrenophora semeniperda on seedling emergence and survival for two native grasses (Pseudoroegneria spicata and Elymus elymoides), by manipulating B. tectorum densities and P. semeniperda inoculum loads in randomized plots. …


A Proteolytic Process To Simulate The Mechanics Of Disc Dengeration In Bovine Cadaveric Tissue, Timothy A. Bishop Mar 2011

A Proteolytic Process To Simulate The Mechanics Of Disc Dengeration In Bovine Cadaveric Tissue, Timothy A. Bishop

Theses and Dissertations

Purpose. The present work hypothesized that proteolytic dissolution of intervertebral discs could induce biomechanical change comparable to the change observed in natural disc degeneration. A method to do such could be utilized for in vitro research where intersample differences in geometry and chemical makeup render it difficult to compare and aggregate results into generalized conclusions.
Methods. Forty-one bovine coccygeal intervertebral discs were isolated with individual functional spinal units. Samples were loaded in three modes: compression/tension, flexion/extension, and axial rotation. The anulus fibrosus of each disc was injected with 200µl trypsin or fetal bovine serum (control) and incubated for an allotted …


Developing Methods To Assess The Potential Effects Of Global Climate Change On Deer Creek Reservoir Using Water Quality Modeling, Reed Earl Chilton Mar 2011

Developing Methods To Assess The Potential Effects Of Global Climate Change On Deer Creek Reservoir Using Water Quality Modeling, Reed Earl Chilton

Theses and Dissertations

To evaluate the potential impacts of future climate change on a temperate reservoir, I used a calibrated water quality and hydrodynamic model validated using three years of data (2007-2009) from Deer Creek Reservoir (Utah). I evaluated the changes due to altered air temperatures, inflow rates, and nutrient loads that might occur under Global Climate Change (GCC). I developed methods to study GCC on reservoirs. I produced Average Water Temperature Plots, Stratification Plots, and Total Concentration Plots. Average Water Temperature Plots show the sensitivity of the water temperature to various parameters. Stratification Plots quantify stratification length and strength as well as …


Culvert Roughness Elements For Native Utah Fish Passage: Phase I, Lindsay D. Esplin Mar 2011

Culvert Roughness Elements For Native Utah Fish Passage: Phase I, Lindsay D. Esplin

Theses and Dissertations

Culverts can increase stream velocities as a result of reduced waterway areas and prevent upstream passage of small non-salmonid fish such as the Native Utah Leatherside chub (Gila copei) and Longnose dace (Rhinichthyscataractae). To mitigate this problem, current culvert design standards for fish passage match sustained fish swim speeds with average cross sectional velocity through the culvert. Such policies dictate relatively large barrels and do not recognize the role of reduced velocity zones near culvert boundaries. Obstacles and streambed substrate create turbulent regions with lower velocity zones that can increase upstream fish passage. A comparison of …


Human Endogenous Sodium Pump Inhibitors Measurement, Source, Synthesis And Regulation, Jie Ma Mar 2011

Human Endogenous Sodium Pump Inhibitors Measurement, Source, Synthesis And Regulation, Jie Ma

Theses and Dissertations

The sodium pump (SP or Na+,K+-ATPase) is a membrane embedded protein complex that pumps 3 sodium ions out and 2 potassium ions into the cell per cycle and in so doing creates a cell membrane electrochemical potential. The membrane potential is critical for any functional cell. In the vasculature, reduction in the voltage potential causes vascular smooth muscle contraction and a narrowing of blood vessels (vasoconstriction) which can lead to increased blood pressure (hypertension). Substantial research over the past several decades has provided a vast amount of research on SP inhibitors, sometimes called endogenous digitalis-like factors (EDLF). Increased levels of …