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Full-Text Articles in Life Sciences

Historical Biogeography Of Velvet Ants (Hymenoptera: Mutillidae) In The North American Deserts And Arid Lands, Joseph S. Wilson Dec 2010

Historical Biogeography Of Velvet Ants (Hymenoptera: Mutillidae) In The North American Deserts And Arid Lands, Joseph S. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries, scientists have been intrigued by the high amount of biodiversity that is found in the deserts of North America. Recently, several studies have investigated the causes of the high diversity found in desert-dwelling mammals, reptiles, and amphibians. These studies have found that many of these organisms seem to have diversified in response to the same historical events. Little work has been done, however, on diverse desert-dwelling insect groups. In this dissertation, I investigate the patterns of genetic diversity in four groups of nocturnal wasps called velvet ants. I compare the patterns of genetic diversity to the historical events …


The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti Dec 2010

The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The San Luis Valley is a large valley formation in Colorado surrounded on either side by mountain ranges exceeding 4,267 m. Within the Valley, two of the 14 amphibian and reptile species are dwarfed: the short-horned lizard (Phrynosoma hernandesi) and the Great Plains toad (Anaxyrus cognatus). Since its initial reporting in 1968 and confirmation in 1981, no research further investigating this dwarfism has been conducted. I collected morphological measurements to determine the extent and patterns of dwarfism of both species. I then investigated the genetics of both species using mitochondrial DNA to determine whether they are …


Selective Biochlorination Of Hydroxyquinolines By A Flavin-Dependent Halogenase, Fuchao Xu, Amanda Merkley, Dayu Yu, Jixun Zhan Oct 2010

Selective Biochlorination Of Hydroxyquinolines By A Flavin-Dependent Halogenase, Fuchao Xu, Amanda Merkley, Dayu Yu, Jixun Zhan

Biological Engineering Faculty Publications

Rdc2 is a flavin-dependent halogenase from Pochonia chlamydosporia. Through the introduction of a His6-tag to both the N- and C-termini, the isolation yield of Rdc2 from Escherichia coli using Ni-NTA affinity chromatography was increased by three-fold. In vitro reaction of Rdc2 and a flavin reductase (Fre) with seven different hydroxyquinolines revealed that 3-hydroxyquinoline (3), 5-hydroxyquinoline (5), 6-hydroxyquinoline (6), and 7-hydroxyquinoline (7) can be specifically halogenated. These products were prepared by incubating the corresponding substrates with IPTG-induced E. coli BL21(DE3)/Rdc2. They were respectively characterized as 3-hydroxy-4-chloroquinoline (3a), 5-hydroxy-6-chloroquinoline (5a), 5-chloro-6-hydroxyquinoline (6a), and 7-hydroxy-8-chloroquinoline (7a) by NMR and MS …


Effects Of Pluronics On A Beneficial Soil Microbe Pseudomonas Putida Strain Kt2440, Priyanka Gajjar May 2010

Effects Of Pluronics On A Beneficial Soil Microbe Pseudomonas Putida Strain Kt2440, Priyanka Gajjar

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report summarizes the effects of a range of Pluronics on cellular responses in bacterial and mammalian cells through a review of published findings. Effects of Pluronics on drug delivery, efflux systems, growth, and nutrition are reported for eukaryotic cells. For microbial cells, their effects on adhesion, movement, biofilm formation, energy status and secondary metabolism are discussed. Guided by findings in the literature, a series of experiments were conducted exploring the responses of a beneficial environmental soil microbe, Pseudomonas putida strain KT2440, to selected Pluronics. These results are presented. The report has four sections: an Introduction 4 that covers published …


Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu May 2010

Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular …


Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel May 2010

Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last several decades, the use of solitary bees as an alternative to honey bees (Apis mellifera L.) for pollination of commercial crops has increased, in part as a response to ongoing problems faced by commercial honey bee populations. Two solitary bee species have exhibited great commercial potential: the blue orchard bee, Osmia lignaria Say, and the alfalfa leafcutting bee, Megachile rotundata Fabricius (Hymenoptera: Megachilidae). However, growth of O. lignaria and M. rotundata populations is limited in commercial systems, mainly due to low establishment of females at provided nesting sites, possibly due to mortality, dispersal, or other causes. …


Survival Of Mycoplasma Species In Recycled Bedding Sand And Possible Implications For Disease Transmission To Ruminants, Anne E. Justice-Allen May 2010

Survival Of Mycoplasma Species In Recycled Bedding Sand And Possible Implications For Disease Transmission To Ruminants, Anne E. Justice-Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mycoplasmas are a group of bacteria which are small in size, lack a cell wall, and have small genomes in comparison to other bacteria. The members of the group that are pathogenic utilize several mechanisms to evade the host's immune system. These processes affect surveillance and control mechanisms such as serologic testing and vaccination. Many of these organisms cause diseases of livestock, which heavily impact production parameters such as weight gain, milk yield, and egg production. Mycoplasmas also cause disease in people.

Mycoplasma spp. can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. …


Acyl Homoserine Lactone Signaling In Pseudomonas Chlororaphis 06, Anna Hegsted May 2010

Acyl Homoserine Lactone Signaling In Pseudomonas Chlororaphis 06, Anna Hegsted

Undergraduate Honors Capstone Projects

Pseudomonas chlororaphis (PcO6), a rhizosphere bacterium, is important to agriculture because of its use as a biological control against fungus and other pests. This biological control correlates with production of phenazines; a process regulated by acyl homoserine lactones (AHSLs). Long chain AHSLs might also have an affect on the production of phenazines. My research showed that PcO6 produced long chain AHSLs and that production is affected by nutrition with more long chain AHSLs produced in rich medium than minimal medium. The nutritional studies and findings with different mutants of PcO6 altered in phenazine production suggest that control of these antifungal …


Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd May 2010

Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased snowmobile use in mountainous terrain has been highlighted as a conservation concern for some Canada lynx (Lynx canadensis) populations. Snow compaction resulting from winter recreation may potentially facilitate access by coyotes (Canis latrans) to habitats used by lynx during winter. Increased interactions could result in either exploitation or interference competition between the two species. Two recent, yet geographically distinct, studies showed contrasting findings regarding coyote movements and their use of snow-compacted trails during the winter. These findings suggest coyote association with snow-compacted trails may be regionally specific and dependent upon ecosystem dynamics and snow characteristics. …


An Entrepreneurial Approach To Librarianship, Flora G. Shrode, Jennifer R. Duncan, Wendy Holliday Apr 2010

An Entrepreneurial Approach To Librarianship, Flora G. Shrode, Jennifer R. Duncan, Wendy Holliday

Flora Shrode

Librarians from Utah State University explain recent efforts to encourage subject librarians to take a more holistic view of their roles. We are shifting from a traditional emphasis primarily on collection development and refocusing on natural connections between collections, instruction, liaison, and reference service. The poster provides background about Utah State University’s situation and explains our approach to analyzing local needs and culture to inform development of a new organizational structure. We describe our vision of subject librarianship, the process by which we assessed librarians’ ideas and goals for performing as subject librarians, and the actions we are taking to …


An Entrepreneurial Approach To Librarianship, Flora Shrode, Jennifer Duncan, Wendy Holliday Apr 2010

An Entrepreneurial Approach To Librarianship, Flora Shrode, Jennifer Duncan, Wendy Holliday

Library Faculty & Staff Publications

Librarians from Utah State University explain recent efforts to encourage subject librarians to take a more holistic view of their roles. We are shifting from a traditional emphasis primarily on collection development and refocusing on natural connections between collections, instruction, liaison, and reference service. The poster provides background about Utah State University’s situation and explains our approach to analyzing local needs and culture to inform development of a new organizational structure. We describe our vision of subject librarianship, the process by which we assessed librarians’ ideas and goals for performing as subject librarians, and the actions we are taking to …


Behavioral And Chemical Ecology Of Marine Organisms With Respect To Tetrodotoxin, Becky L. Williams Feb 2010

Behavioral And Chemical Ecology Of Marine Organisms With Respect To Tetrodotoxin, Becky L. Williams

Biology Faculty Publications

The behavioral and chemical ecology of marine organisms that possess tetrodotoxin (TTX) has not been comprehensively reviewed in one work to date. The evidence for TTX as an antipredator defense, as venom, as a sex pheromone, and as an attractant for TTX-sequestering organisms is discussed. Little is known about the adaptive value of TTX in microbial producers; thus, I focus on what is known about metazoans that are purported to accumulate TTX through diet or symbioses. Much of what has been proposed is inferred based on the anatomical distribution of TTX. Direct empirical tests of these hypotheses are absent in …


The Evolution Of Chloroplast Genome Structure In Ferns, Paul G. Wolf, J. M. Roper, A. M. Duffy Jan 2010

The Evolution Of Chloroplast Genome Structure In Ferns, Paul G. Wolf, J. M. Roper, A. M. Duffy

Biology Faculty Publications

The plastid genome (plastome) is a rich source of phylogenetic and other comparative data in plants. Most land plants possess a plastome of similar structure. However, in a major group of plants, the ferns, a unique plastome structure has evolved. The gene order in ferns has been explained by a series of genomic inversions relative to the plastome organization of seed plants. Here, we examine for the first time the structure of the plastome across fern phylogeny. We used a PCR-based strategy to map and partially sequence plastomes. We found that a pair of partially overlapping inversions in the region …


Chloroplast Genome Sequence Of The Moss Torula Ruralis: Gene Content, Polymorphism, And Structural Arrangement Relative To Other Green Plant Chloroplast Genomes, M. J. Oliver, A. G. Murdock, B. D. Mishler, J. V. Kuehl, J. L. Boore, D. F. Mandoli, K. D. E. Everett, Paul G. Wolf, A. M. Duffy, K. G. Karol Jan 2010

Chloroplast Genome Sequence Of The Moss Torula Ruralis: Gene Content, Polymorphism, And Structural Arrangement Relative To Other Green Plant Chloroplast Genomes, M. J. Oliver, A. G. Murdock, B. D. Mishler, J. V. Kuehl, J. L. Boore, D. F. Mandoli, K. D. E. Everett, Paul G. Wolf, A. M. Duffy, K. G. Karol

Biology Faculty Publications

Background Tortula ruralis, a widely distributed species in the moss family Pottiaceae, is increasingly used as a model organism for the study of desiccation tolerance and mechanisms of cellular repair. In this paper, we present the chloroplast genome sequence of T. ruralis, only the second published chloroplast genome for a moss, and the first for a vegetatively desiccation-tolerant plant. Results The Tortula chloroplast genome is ~123,500 bp, and differs in a number of ways from that of Physcomitrella patens, the first published moss chloroplast genome. For example, Tortula lacks the ~71 kb inversion found in the large single copy region …


Complete Plastome Sequences Of Equisetum Arvense And Isoetes Flaccida: Implications For Phylogeny And Plastid Genome Evolution Of Early Land Plant Lineages, K. G. Karol, K. Arumuganthan, J. L. Boore, A. M. Duffy, K. D. E. Everett, J. D. Hall, S. K. Hansen, J. V. Mandoli, D. F. Mandoli, B. D. Mishler, R. G. Olmstead, K. S. Renzaglia, Paul G. Wolf Jan 2010

Complete Plastome Sequences Of Equisetum Arvense And Isoetes Flaccida: Implications For Phylogeny And Plastid Genome Evolution Of Early Land Plant Lineages, K. G. Karol, K. Arumuganthan, J. L. Boore, A. M. Duffy, K. D. E. Everett, J. D. Hall, S. K. Hansen, J. V. Mandoli, D. F. Mandoli, B. D. Mishler, R. G. Olmstead, K. S. Renzaglia, Paul G. Wolf

Biology Faculty Publications

Background Despite considerable progress in our understanding of land plant phylogeny, several nodes in the green tree of life remain poorly resolved. Furthermore, the bulk of currently available data come from only a subset of major land plant clades. Here we examine early land plant evolution using complete plastome sequences including two previously unexamined and phylogenetically critical lineages. To better understand the evolution of land plants and their plastomes, we examined aligned nucleotide sequences, indels, gene and nucleotide composition, inversions, and gene order at the boundaries of the inverted repeats. Results We present the plastome sequences of Equisetum arvense, a …


Unfurling Fern Biology In The Genomics Age, M. S. Barker, Paul G. Wolf Jan 2010

Unfurling Fern Biology In The Genomics Age, M. S. Barker, Paul G. Wolf

Biology Faculty Publications

Twenty-first century technology is addressing many of the questions posed by 20th-century biology. Although the new approaches, especially those involving genomic data and bioinformatic tools, were first applied to model organisms, they are now stretching across the tree of life. Here, we review some recent revelations in the ferns. We first examine how DNA sequence data have contributed to our understanding of fern phylogeny. We then address evolution of the fern plastid genome, including reports of high levels of RNA editing. Recent studies are also shedding light on the evolution of fern nuclear genomes. Initial analyses of genomic data suggest …


Teaching Species, Mark W. Ellis, Paul G. Wolf Jan 2010

Teaching Species, Mark W. Ellis, Paul G. Wolf

Biology Faculty Publications

A clear understanding of the term "species" is fundamental to the subject of evolution. However, introductory textbooks often fail to address this topic until one of the later chapters, after having used the term species in all preceding chapters. Furthermore, definitions of terms critical to a clear understanding of this subject are often vague or absent in chapters on species concepts. We feel the popular notion of a "species problem" has been unnecessarily inflated by this less-than-effective educational approach. Clearly addressing this essential subject at the beginning of a course on evolution will prepare students to learn the details and …


The Combined Influence Of The Local Environment Andregional Enrichment On Bird Species Richness, Ethan P. White, A. H. Hurlbert Jan 2010

The Combined Influence Of The Local Environment Andregional Enrichment On Bird Species Richness, Ethan P. White, A. H. Hurlbert

Biology Faculty Publications

It is generally accepted that local species richness at a site reflects the combined influence of local and regional processes. However, most empirical studies evaluate the influence of either local environmental variables or regional enrichment but not both simultaneously. Here we demonstrate the importance of combining these processes to understand continental scale richness patterns in breeding birds. We show that neither regional enrichment nor the local environment in isolation is sufficient to characterize observed patterns of species richness. Combining both sets of variables into a single model results in improved model fit and the removal of residual spatial autocorrelation. At …


Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly Jan 2010

Loss Of Foundation Species Increases Population Growth Of Exotic Forbs In Sagebrush Steppe, J S. Prevey, M J. Germino, Nancy J. Huntly

Biology Faculty Publications

The invasion and spread of exotic plants following land disturbance threatens semiarid ecosystems. In sagebrush steppe, soil water is scarce and is partitioned between deeprooted perennial shrubs and shallower-rooted native forbs and grasses. Disturbances commonly remove shrubs, leaving grass-dominated communities, and may allow for the exploitation of water resources by the many species of invasive, tap-rooted forbs that are increasingly successful in this habitat. We hypothesized that exotic forb populations would benefit from increased soil water made available by removal of sagebrush, a foundation species capable of deep-rooting, in semiarid shrub-steppe ecosystems. To test this hypothesis, we used periodic matrix …


Seasonal Patterns Of Arthropod Diversity And Abundance On Big Sagebrush, Artemisia Trientata, M P. Stanford, Nancy J. Huntly Jan 2010

Seasonal Patterns Of Arthropod Diversity And Abundance On Big Sagebrush, Artemisia Trientata, M P. Stanford, Nancy J. Huntly

Biology Faculty Publications

The sagebrush biotype is the largest in the western United States. This vast sagebrush community is thought to harbor equally vast and diverse arthropod communities, but these remain little explored. Our objective was to examine the diversity, abundance, and seasonal phenology of arthropod taxa found on the dominant shrub of the sagebrush ecosystem, big sagebrush (Artemisia tridentata). We wanted to improve understanding of this little-studied arthropod assemblage that may play significant roles in the dynamics of sagebrush populations and the sagebrush ecosystem. We sampled free-living and gall-forming arthropods from a stratified random sample of sagebrush plants at the Barton Road …