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Effects Of Exposure To Perinatal Ultrasound Radiation On Information Processing In The Auditory System, Jennifer Burnett Apr 2007

Effects Of Exposure To Perinatal Ultrasound Radiation On Information Processing In The Auditory System, Jennifer Burnett

Theses and Dissertations

Ultrasound (US) has become a standard procedure used during pregnancy to document the health and development of a fetus. When ultrasound was first developed, some researchers urged caution, suggesting that the possibility of hazard should be kept under constant review. Given the routine application of fetal ultrasound imaging, any possibility of deleterious developmental effects resulting from its use is an important public health issue. Rats have a well characterized central nervous system whose neurochemical pathways and neuronal electrophysiology qualitatively correspond to those of humans. Because of this, we opted to use Wistar rats as an animal model to document effects …

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Economic Hardship And Children's Social Withdrawal In Romanian Families, Jennifer Denise Pearson Apr 2007

Economic Hardship And Children's Social Withdrawal In Romanian Families, Jennifer Denise Pearson

Theses and Dissertations

This study examined the impact of perceived economic hardship on family processes and children's socially withdrawn (reticent) behaviors in Romania. The sample consisted of 121 Romanian mothers and fathers of 4-5 year old children, as well as children's kindergarten teachers. Drawing on Conger and colleagues' family stress model of economic hardship, the associations among mothers' and fathers' ratings of economic hardship, depression, marital conflict, psychologically controlling parenting, and teacher ratings of child social withdrawal were analyzed. Structural equation modeling using AMOS 7.0 was used to test the model. Findings generally support earlier studies with European American families, as well as …

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Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu Apr 2007

Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu

Theses and Dissertations

In chapter 1, we describe development of a mild and efficient method for SNAr iodination of 6-chloropurine 2'-deoxynucleosides and nucleosides. Our studies demonstrate that 6-iodopurine nucleosides are excellent substrates for certain transition metal-catalyzed cross-coupling reactions. In chapter 2, we describe synthesis of protected 6-fluoro, 6-chloro, 6-bromo and 6-sulfonylpurine nucleosides. Comparisons among 6-fluoro-, 6-chloro-, 6-bromo, 6-iodo and 6-sulfonylpurine nucleosides for SNAr reactions with various N, O and S nucleophiles were investigated. Our results demonstrate that the 6-fluoropurine nucleoside is the best substrate for SNAr reactions among the four 6-halopurine nucleosides with oxygen, sulfur and aliphatic amine nucleophiles, and also with an …

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An Infection Model For Examining The Effects Of Gender And Diabetic State On Proinflammatory Cytokine Secretion By Phagocytic Cells In Response To Infection With Burkholderia Pseudomallei, Laura L. Dickey Apr 2007

An Infection Model For Examining The Effects Of Gender And Diabetic State On Proinflammatory Cytokine Secretion By Phagocytic Cells In Response To Infection With Burkholderia Pseudomallei, Laura L. Dickey

Theses and Dissertations

Burkholderia pseudomallei is an opportunistic soil pathogen that causes melioidosis, a life-threatening human disease prevalent in Southeast Asia, northern Australia, the Middle East, Africa, and South America. The organism also causes disease in plants and animals. Persons with severe melioidosis usually die of septicemia. Relatively little is known regarding the virulence mechanisms of B. pseudomallei; however, several putative virulence determinants have been identified. The organism is able to invade and replicate within phagocytic cells and is particularly pathogenic in males with diabetes mellitus. B. thailandensis is closely related to B. pseudomallei, but is not pathogenic. This study examines various in …

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Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia Apr 2007

Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia

Theses and Dissertations

Nanomaterials display interesting physical and chemical properties depending on their shape, size and composition. Self assembly is an intriguing route to producing nanomaterials with controllable compositions and morphologies. DNA has been used to guide the self assembly of materials, resulting in: (1) metal nanowires; (2) metal or semiconductor nanorods; (3) carbon nanotubes; and (4) semiconductor, metal or biological nanoparticles. My work expands the range of DNA templated nanomaterials and develops novel ways of using DNA to pattern nanostructures on surfaces. I have performed the first synthesis of silver nanorods on single stranded DNA, an attractive material for localizing DNA coupled …

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Biomass And Coal Fly Ash In Concrete: Strength, Durability, Microstructure, Quantitative Kinetics Of Pozzolanic Reaction And Alkali Silica Reaction Investigations., Shuangzhen Wang Apr 2007

Biomass And Coal Fly Ash In Concrete: Strength, Durability, Microstructure, Quantitative Kinetics Of Pozzolanic Reaction And Alkali Silica Reaction Investigations., Shuangzhen Wang

Theses and Dissertations

Biomass represents an important sustainable energy resource, with biomass-coal cofiring representing among the most effective and cost efficient CO2 reduction strategies. Fly ash generated during coal combustion represents a technically advantageous, inexpensive, and environmentally beneficial admixture in concrete production, partially replacing cement. However, strict interpretation of American Society of Testing and Materials (ASTM) and American Concrete Institute (ACI) standards prohibits use of fly ashes from any source other than coal in concrete production; therefore, fly ash from biomass coal cofiring is excluded from use in concrete. This dissertation discusses biomass impacts on concrete properties through experiments conducted on several combinations …

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Investigation Of Novel Microseparation Techniques, Yansheng Liu Apr 2007

Investigation Of Novel Microseparation Techniques, Yansheng Liu

Theses and Dissertations

Ultrahigh pressure liquid chromatography (UHPLC) makes it possible to use very small particles (< 2 µm) as packing materials to provide high column efficiencies. Results from a careful comparison of small porous and nonporous particles show that when the particle size is small enough (< 2 µm), both porous and nonporous particles give excellent performance, and the differences in column efficiencies between porous and nonporous particles become insignificant. Columns packed with bare diamond particles could separate small molecules, especially polar molecules, however, severe tailing occurred for less polar compounds. The polybutadiene coated diamond particles gave greater retention and better separation of small molecules compared to bare particles, although no improvement in column efficiency was observed. Changes in surface bonding of thermally hydrogenated diamond particles was achieved by chemical modification using various organic peroxides with or without reagents containing long carbon chain functional groups. It appears that the alkyl groups were attached onto the diamond surface with limited coverage. LC experiments did not demonstrate good separation; however, changes in LC behavior were observed. A repetitive solvent programming approach was successfully applied to the analysis of a continuous sample stream in microbore LC. Each analysis cycle consisted of three steps: pseudo-injection, elution and rinse. In the pseudo-injection step, elution with a non- or poor-eluting solvent produced a concentrated sample plug due to on-column focusing. Factors influencing peak symmetry, resolution and analysis cycle length were investigated. Quantitative analysis of a continuous sample stream is possible under certain operating conditions. Electric field gradient focusing (EFGF) devices with distributed resistor substrates could focus proteins in the separation channel, however, the focused bands were not stable, and the repeatability was poor due to the formation of bubbles and pH gradient in the separation channel. Both fiber-based and porous glass capillary-based planar EFGF devices with changing cross-sectional area (CCSA) channels were constructed and evaluated with the aid of a home-made scanning laser-induced fluorescence detection system. The fiber-based CCSA EFGF devices gave poorer performance compared with glass capillary based devices. Porous glass capillary-based EFGF devices could focus single proteins and separate mixtures of two to three proteins.

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Finding Relevant Pdf Medical Journal Articles By The Content Of Their Figures As Well As Their Text, Ammon J. Christiansen Apr 2007

Finding Relevant Pdf Medical Journal Articles By The Content Of Their Figures As Well As Their Text, Ammon J. Christiansen

Theses and Dissertations

This work addresses the need for an alternative to keyword-based search for sifting through large PDF medical journal article document collections for literature review purposes. Despite users' best efforts to form precise and accurate queries, it is often difficult to guess the right keywords to find all the related articles while finding a minimum number of unrelated ones. Failure during literature review to find relevant, related research results in wasted research time and effort in addition to missing significant work in the related area which could affect the quality of the research work being conducted. The purpose of this work …

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Contributions Of Family Leisure To Family Functioning Among Families That Include Children With Developmental Disabilities, Dorthy Clara Hornberger Dodd Apr 2007

Contributions Of Family Leisure To Family Functioning Among Families That Include Children With Developmental Disabilities, Dorthy Clara Hornberger Dodd

Theses and Dissertations

The purpose of this study was to examine the relationship between family leisure involvement and family functioning among families that include children with developmental disabilities. The sample consisted of 154 families (154 parents and 62 youth). Data were analyzed from the parent, youth, and family perspective. The Family Leisure Activity Profile (FLAP) was used to measure family leisure involvement. FACES II was used to measure family functioning. A scale based upon the definition, classification, and systems of support manual of the American Association on Mental Retardation adapted by Dyches was used to measure the level of support needed by the …

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Inhibitory Effects Of Estrogen Receptor Beta On Specific Hormone-Responsive Gene Expression And Association With Disease Outcome In Primary Breast Cancer, Chin-Yo Lin, Anders Strom, Li Say Kong, Silke Kietz, Jane S. Thomsen, Jason B. S. Tee, Vinsensius B. Vega, Lance D. Miller, Johanna Smeds, Jonas Bergh, Jan-Ake Gustafsson, Edison T. Liu Apr 2007

Inhibitory Effects Of Estrogen Receptor Beta On Specific Hormone-Responsive Gene Expression And Association With Disease Outcome In Primary Breast Cancer, Chin-Yo Lin, Anders Strom, Li Say Kong, Silke Kietz, Jane S. Thomsen, Jason B. S. Tee, Vinsensius B. Vega, Lance D. Miller, Johanna Smeds, Jonas Bergh, Jan-Ake Gustafsson, Edison T. Liu

Faculty Publications

The impact of interactions between the two estrogen receptor (ER) subtypes, ER(alpha) and ER(beta), on gene expression in breast cancer biology is not clear. The goal of this study was to examine transcriptomic alterations in cancer cells co-expressing both receptors and the association of gene expression signatures with disease outcome. Methods: Transcriptional effects of ER(beta) overexpression were determined in a stably transfected cell line derived from ER(alpha) -positive T-47D cells. Microarray analysis was carried out to identify differential gene expression in the cell line, and expression of key genes was validated by quantitative polymerase chain reaction. Microarray and clinical data …

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Hikorocodium Endo Is Not An Alga But An Inozoid Sponge, J. Keith Rigby, Baba Senowbari-Daryan Apr 2007

Hikorocodium Endo Is Not An Alga But An Inozoid Sponge, J. Keith Rigby, Baba Senowbari-Daryan

Faculty Publications

The genus Hikorocodium, with the type species Hikorocodium elegantae from the Permian of Japan, was described originally as a codiacean alga by Endo. It is not a codiacean alga but an inozoid sponge of the family Preperonidellidae. Several fossils described later by Endo and other authors as H. elegantae should be assigned to different inozoid sponge taxa. Specimens of H. fertiliz, described by Endo from the Jurassic of Japan, are also sponge fragments. The taxonomic positions of H. transversum Endo and H. kuramotoi Nakamura, as sponges or

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Eating, Substance Use, And Body Image: A Comparison Of Latter-Day Saint And Non-Latter-Day Saint College Age Females, Monika Sandberg, Diane L. Spangler Apr 2007

Eating, Substance Use, And Body Image: A Comparison Of Latter-Day Saint And Non-Latter-Day Saint College Age Females, Monika Sandberg, Diane L. Spangler

Issues in Religion and Psychotherapy

This study examined differences between Latter-day Saint (LDS) and non-Latter-day-Saint (non-LDS) females in desire to engage in substance use and eating behaviors in response to negative emotion. Additionally, differences between LDS and non-LDS females regarding body image, as well as body image differences between LDS females residing inside Utah and outside Utah, were explored. Findings suggested that non-LDS females were more likely to experience increased urges to use substances in response to negative emotion than LDS females, consistent with LDS doctrine teaching the aviodance of substance use. LDS females also did not appear to substitute LDS-sanctioned eating behaviors for substance …

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Vol. 09 No. 1 Esr Review, Esr Review Apr 2007

Vol. 09 No. 1 Esr Review, Esr Review

Journal of Microfinance / ESR Review

No abstract provided.

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The Midlife Client, Patricia Evans Apr 2007

The Midlife Client, Patricia Evans

Issues in Religion and Psychotherapy

This case study explored the midlife physical, emotional, and role changes or a small sample of women of the Church of Jesus Christ of Latter-day Saints (LDS) to determine how they cope with midlife change, to examine their aging experience within the LDS Church community, and to discover how the LDS faith and church community helped them through the challenges of midlife. According to a qualitiative design, the researcher implemented in-depth interviews with 10 LDS women from three cohorts: ages 35-44, 45-54, 55-65. Three theoretical perspectives were used to frame the study: feminist, social constructionist, and narrative. A qualitiative matrix …

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Using World History To Predict The Future Of The First Civilization, William Mcgaughey Apr 2007

Using World History To Predict The Future Of The First Civilization, William Mcgaughey

Comparative Civilizations Review

No abstract provided.

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Family Issues In Time Of War: A Chaplain's Perspective, Michael D. Howard, Ruth P. Cox Apr 2007

Family Issues In Time Of War: A Chaplain's Perspective, Michael D. Howard, Ruth P. Cox

Issues in Religion and Psychotherapy

Military families experience many stressors that are similar to those of non-military families and others that are more common to military life. Stressors which are more common to military families include enduring forced periods of lengthly separation, raising a family with only one parent for extended periods, experiencing frequent forced moves, and being away from the extended family. In addition to these basic stressors are those associated with the harsh reality of war: personal injury, disability, and death. For these families, the future is very uncertain, as is the possibility of never seeing one another again. This paper explores the …

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Editor's Note, Joseph Drew Apr 2007

Editor's Note, Joseph Drew

Comparative Civilizations Review

No abstract provided.

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Banking The Unbanked, Janine Firpo Apr 2007

Banking The Unbanked, Janine Firpo

Journal of Microfinance / ESR Review

No abstract provided.

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Federated Searching: Do Undergraduates Prefer It And Does It Add Value?, C. Jeffrey Belliston, Jared L. Howland, Brian C. Roberts Apr 2007

Federated Searching: Do Undergraduates Prefer It And Does It Add Value?, C. Jeffrey Belliston, Jared L. Howland, Brian C. Roberts

Faculty Publications

Randomly selected undergraduates at Brigham Young University, Brigham Young University Idaho and Brigham Young University Hawaii, all private universities sponsored by The Church of Jesus Christ of Latter-day Saints, participated in a study of federated searching. This paper reports the study results including differences in time spent between searching databases in federated and non-federated fashion, satisfaction with citations gathered using each method, preference between methods, and quality of citations retrieved by each method judged by two different rubrics. Undergraduates rated their satisfaction with the citations gathered by federated searching 6.5% higher than their satisfaction using non-federated search methods. Additionally, 70% …

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Tandem Repeat Regions Within The Burkholderia Pseudomallei Genome And Their Application For High Resolution Genotyping, Richard A. Robison, Jana M. U'Ren, James M. Schupp, Talima Pearson, Heidie Hornstra, Christine L. Friedman Clark, Kimothy L. Smith, Rebecca R. Leadem Daugherty, Shane D. Rhoton, Ben Leadem, Shalamar Georgia, Michelle Cardon, Lynn Y. Huynh, David Deshazer, Steven P. Harvey, Daniel Gal, Mark J. Mayo, David Wagner, Bart J. Currie, Paul Keim Mar 2007

Tandem Repeat Regions Within The Burkholderia Pseudomallei Genome And Their Application For High Resolution Genotyping, Richard A. Robison, Jana M. U'Ren, James M. Schupp, Talima Pearson, Heidie Hornstra, Christine L. Friedman Clark, Kimothy L. Smith, Rebecca R. Leadem Daugherty, Shane D. Rhoton, Ben Leadem, Shalamar Georgia, Michelle Cardon, Lynn Y. Huynh, David Deshazer, Steven P. Harvey, Daniel Gal, Mark J. Mayo, David Wagner, Bart J. Currie, Paul Keim

Faculty Publications

The facultative, intracellular bacterium Burkholderia pseudomalle is the causative agent of melioidosis, a serious infectious disease of humans and animals. We identified and categorized tandem repeat arrays and their distribution throughout the genome of B. pseudomallei strain K96243 in order to develop a genetic typing method for B. pseudomallei. We then screened 104 of the potentially polymorphic loci across a diverse panel of 31 isolates including B. pseudomallei, B. mallei and B. thailandensis in order to identify loci with varying degrees of polymorphism. A subset of these tandem repeat arrays were subsequently developed into a multiple-locus VNTR analysis to examine …

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The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke Mar 2007

The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke

Theses and Dissertations

Phosducin-like protein (PhLP) has been shown to interact with the cytosolic chaperonin containing TCP-1 (CCT), and the βγ subunit dimer of heterotrimeric G proteins (Gβγ). Here we provide details obtained from cryo-electron microscopic and biochemical studies on the structure of the complex between the cytosolic chaperonin CCT and PhLP. Binding of PhLP to CCT occurs through only one of the two chaperonin rings, making multiple contacts with CCT through both its N- and C-terminal domains. In addition, we show that PhLP acts as a co-chaperonin along with CCT in mediating the assembly of the G protein βγ subunit and that …

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Optimizing Product Variant Placement To Satisfy Market Demand, Jonathan Roger Parkinson Mar 2007

Optimizing Product Variant Placement To Satisfy Market Demand, Jonathan Roger Parkinson

Theses and Dissertations

Many companies use product families in order to offer product variants that appeal to different market segments while minimizing costs. Because the market demand is generally not uniform for all possible product variants, during the design phase a decision must be made as to which variants will be offered and how many. This thesis presents a new approach to solving this problem. The product is defined in terms of performance parameters. The market demand is captured in a preference model and applied to these parameters in order to represent the total potential market. The number and placement of the product …

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The Effect Of Elevation On The Distribution Of Sibling Species In The Simulium Arcticum Complex (Diptera: Simuliidae), Gerald F. Shields, Gregory M. Clausen, Christina S. Marchion, Tracy L. Michel, Kathryn C. Styren, Callie N. Riggin, Tonya D. Santoro, Lindee M. Strizich Mar 2007

The Effect Of Elevation On The Distribution Of Sibling Species In The Simulium Arcticum Complex (Diptera: Simuliidae), Gerald F. Shields, Gregory M. Clausen, Christina S. Marchion, Tracy L. Michel, Kathryn C. Styren, Callie N. Riggin, Tonya D. Santoro, Lindee M. Strizich

Western North American Naturalist

At least 5 sibling species and an additional 11 cytotypes of the Simulium arcticum complex occur in Montana. Consequently, this speciose complex might allow study of environmental correlates with genetic differentiation. We used conventional methods of collection and cytogenetic analysis to study 1128 male larvae of the Simulium arcticum complex at 15 sites within 5 drainages in western Montana to test the hypothesis that distribution of siblings is associated with elevation. We sampled at the mouth, at the headwaters, and at an intermediate site to span the range of elevations within each drainage. We restricted our analyses to the most …

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Spotted Cotton Oligonucleotide Microarrays For Gene Expression Analysis, Joshua Udall, Lex E. Flagel, Foo Chung, Andrew W. Woodward, Ran Hovav, Ryan A. Rapp, Jordan M. Swanson, Jinsuk J. Lee, Alan R. Gingle, Dan Nettleton, Christopher D. Town, Z. Jeffrey Chen, Jonathan F. Wendel Mar 2007

Spotted Cotton Oligonucleotide Microarrays For Gene Expression Analysis, Joshua Udall, Lex E. Flagel, Foo Chung, Andrew W. Woodward, Ran Hovav, Ryan A. Rapp, Jordan M. Swanson, Jinsuk J. Lee, Alan R. Gingle, Dan Nettleton, Christopher D. Town, Z. Jeffrey Chen, Jonathan F. Wendel

Faculty Publications

Microarrays offer a powerful tool for diverse applications plant biology and crop improvement. Recently, two comprehensive assemblies of cotton ESTs were constructed based on three Gossypium species. Using these assemblies as templates, we describe the design and creation and of a publicly available oligonucleotide array for cotton, useful for all four of the cultivated species. Results: Synthetic oligonucleotide probes were generated from exemplar sequences of a global assembly of 211,397 cotton ESTs derived from <50 different cDNA libraries representing many different tissue types and tissue treatments. A total of 22,787 oligonucleotide probes are included on the arrays, optimized to target the diversity of the transcriptome and previously studied cotton genes, transcription factors, and genes with homology to Arabidopsis. A small portion of the oligonucleotides target unidentified protein coding sequences, thereby providing an element of gene discovery. Because many oligonucleotides were based on ESTs from fiber-specific cDNA libraries, the microarray has direct application for analysis of the fiber transcriptome. To illustrate the utility of the microarray, we hybridized labeled bud and leaf cDNAs from G. hirsutum and demonstrate technical consistency of results. Conclusion: The cotton oligonucleotide microarray provides a reproducible platform for transcription profiling in cotton, and is made publicly available through http://cottonevolution.info.

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Spatially Scaled Response Of A Lazuli Bunting Population To Fire, Andreas Leidolf, Tim Nuttle, Michael L. Wolfe Mar 2007

Spatially Scaled Response Of A Lazuli Bunting Population To Fire, Andreas Leidolf, Tim Nuttle, Michael L. Wolfe

Western North American Naturalist

We examined the response of Lazuli Bunting (Passerina amoena) to fire in Gambel oak (Quercus gambelii) woodland at Camp Williams, Utah, during 1993–1998. Overall, Lazuli Bunting abundance on the study area increased significantly during the 2 years after a stand-replacing wildfire, which covered 800 ha of Gambel oak woodland. This increase suggested that Lazuli Buntings respond positively to fire. However, a comparison of pre- and post-fire abundance of Lazuli Bunting for 2 groups of monitoring plots with different fire histories showed that abundance was significantly greater during the post-fire period for both burned and unburned plots. …

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Vegetation Responses To 35 And 55 Years Of Native Ungulate Grazing In Shrubsteppe Communities, Echo A. Rexroad, Karen H. Beard, Andrew Kulmatiski Mar 2007

Vegetation Responses To 35 And 55 Years Of Native Ungulate Grazing In Shrubsteppe Communities, Echo A. Rexroad, Karen H. Beard, Andrew Kulmatiski

Western North American Naturalist

Ungulate populations are managed in shrubsteppe ecosystems around the world, but relatively few long-term datasets are available that test the impacts of these grazers on shrubsteppe structure and function. This study evaluated 8 exclosures in 4 shrubsteppe communities to determine the effects of deer and elk over 35 or 55 years on (1) plant biomass and species composition, (2) soil nitrogen (N) mineralization and net nitrification rates, Olsen extractable phosphorus (P), and C:N ratios, and (3) arthropod diversity and abundance. The site with deer, the highest ungulate densities, and coldest climate (Sinlahekin Wildlife Area, WA) had greater vegetative biomass and …

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Modeling Distributions Of Rare Plants In The Great Basin, Western North America, M. Aitken, D. W. Roberts, L. M. Shultz Mar 2007

Modeling Distributions Of Rare Plants In The Great Basin, Western North America, M. Aitken, D. W. Roberts, L. M. Shultz

Western North American Naturalist

In this 2-phase study, we developed field-validated site and landscape-level predictive models for identifying potential rare and endemic plant habitat in the Great Basin of western North America. Four species were chosen to include a range of environmental variability and plant communities. Herbarium records of known occurrences were used to identify initial sample sites. The geographic coordinates, environmental attributes, and vegetation data collected at each site were used to develop 2 predictive models for each species: a field key and a probability-of-occurrence or predictor map. The field key was developed using only field data collected at the sites on environmental …

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Winter Survival Of Northern Pintails In The Middle Rio Grande Valley, New Mexico, Colin K. Lee, John P. Taylor, David A. Haukos, Mark C. Andersen Mar 2007

Winter Survival Of Northern Pintails In The Middle Rio Grande Valley, New Mexico, Colin K. Lee, John P. Taylor, David A. Haukos, Mark C. Andersen

Western North American Naturalist

In response to continued low population numbers of Northern Pintail (Anas acuta) in North America and to increase knowledge of the geographic variation in pintail survival rates, we estimated 126-day (27 October–2 March) survival for male and female pintails wintering in the Middle Rio Grande Valley, New Mexico, during 2001–2002 (SY1) and 2002–2003 (SY2). Sixty-nine adult male and female pintails were marked with radio-transmitters and tracked throughout the study period. Weekly relocation data in relation to study year, sex, time (week), body condition at capture, and hunting seasons were modeled using the known-fate procedure in Program MARK. Year, …

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Food And Habitat Relationships Of Claassenia Sabulosa (Plecoptera: Perlidae) In The Upper Colorado River, Colorado, Richard A. Thorp, Jeremy B. Monroe, Emily C. Thorp, Todd Wellnitz, N. Leroy Poff Mar 2007

Food And Habitat Relationships Of Claassenia Sabulosa (Plecoptera: Perlidae) In The Upper Colorado River, Colorado, Richard A. Thorp, Jeremy B. Monroe, Emily C. Thorp, Todd Wellnitz, N. Leroy Poff

Western North American Naturalist

Streambed surveys were conducted along the upper Colorado River, Colorado, to describe the distributions of Claassenia sabulosa larvae in relation to current speed and to determine their diets. We also addressed diel feeding periodicity by sampling during both day and night. Claassenia sabulosa was more abundant in riffle habitats than in runs. A positive relationship existed between C. sabulosa abundance and stream current, with larval size increasing with current speed. Chironomidae, Baetidae, and Simulidae collectively accounted for 93% of the prey found in stonefly guts; however, these categories were not consumed equally by all C. sabulosa. Smaller C. sabulosa …

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Aspen And Conifer Heterogeneity Effects On Bird Diversity In The Northern Yellowstone Ecosystem, Jeff P. Hollenbeck, William J. Ripple Mar 2007

Aspen And Conifer Heterogeneity Effects On Bird Diversity In The Northern Yellowstone Ecosystem, Jeff P. Hollenbeck, William J. Ripple

Western North American Naturalist

We addressed the following question: Do conifers within aspen stands (conifer invasion) increase bird species diversity in western landscapes? We tested the hypotheses that bird species diversity, measured as species richness or with the Shannon-Weiner diversity index, responds to aspen-conifer ratios (from 0% to 100% conifer) in a quadratic manner with a maximum occurring at an intermediate ratio of aspen and conifer. Extra sum-of-squares F tests comparing quadratic with linear models suggested that migratory bird diversity was inversely linearly related to the extent of conifer invasion. These linear responses were moderate (species richness: R2 ≥ 0.34, P < 0.01; Shannon-Weiner diversity index: R2 ≥ …

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