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2009

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Articles 151 - 180 of 812

Full-Text Articles in Biology

Fecal-Sac Ingestion By Spotted Towhees, Jenny E. Mckay, Michael T. Murphy, Sarah Bartos Smith, Jennifer K. Richardson Aug 2009

Fecal-Sac Ingestion By Spotted Towhees, Jenny E. Mckay, Michael T. Murphy, Sarah Bartos Smith, Jennifer K. Richardson

Biology Faculty Publications and Presentations

Altricial nestlings encase excrement in fecal sacs that parents remove by either ingesting them or transporting them away from the nest. Ingestion may allow energetically or nutritionally deprived parents to recapture energy or nutrients that might be lost because of nestlings' inefficient digestion (the "parental-nutrition hypothesis"), but ingestion may also permit parents to avoid flights from the nest that interfere with parental care (e.g., brooding young; the "economic-disposal hypothesis"). We used a hypothetico-deductive approach to test the two hypotheses' ability to account for fecal-sac ingestion by the Spotted Towhee (Pipilo maculatus). We confirmed the parental-nutrition hypothesis' predictions that …

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Serotonin Immunoreactive Cells And Nerve Fibers In The Mucosa Of The Rat Stomach, A P Gesase Jul 2009

Serotonin Immunoreactive Cells And Nerve Fibers In The Mucosa Of The Rat Stomach, A P Gesase

Tanzania Journal of Science

The current study has showed the morphological features of serotonin (5-hydroxytryptamine) immunoreactivity in the pyloric mucosa of the rat stomach. The immunoreactive elements included the endocrine cells, mast cells and mucosal nerve fibers in the lamina propria. The immunopositive endocrine cells were oval in shape and located mostly in the basal part of the gastric glands. The cell contained a central non-staining area and the peripheral staining zone. The mast cells stained homogenously and appeared to be oval-round in shape. They were located in the upper, middle and basal parts of the mucosa. Serotonin immunoreactive nerve fibers with varicosities were …

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Morphological Features Of Tyrosine Hydroxylase Immunoreactive Cells In The Mouse Islets Of Langerhans, A P Gesase, Y -I Satoh Jul 2009

Morphological Features Of Tyrosine Hydroxylase Immunoreactive Cells In The Mouse Islets Of Langerhans, A P Gesase, Y -I Satoh

Tanzania Journal of Science

The current immunohistochemical study used the antibody against tyrosine hydroxylase (TH) to observe the immunoreactive elements in the mouse pancreas. The results indicated the presence of immunoreactive nerve fibers and endocrine cells. The immunopositive nerve fibers appeared as thick and thin bundles; thick bundles were seen to run along the blood vessels giving out fine fibers to the wall. Varicose nerve fibers were seen in the islets of Langerhans and also in close association with the exocrine endpieces. The TH immunoreactive cells were oval-round in shape and some showed the central non-staining area and the dense staining peripheral zone. More …

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Effects Of Biofilm Age And Composition On Oyster Larval Setting, Alaina Hart Jul 2009

Effects Of Biofilm Age And Composition On Oyster Larval Setting, Alaina Hart

Theses and Dissertations

The lack of success in restoring oyster, Crassostrea virginica, populations to Chesapeake Bay and its tributaries has raised many questions about why many restoration efforts have failed. A number of studies have focused on the larval stage of oysters and considered the variables that impact oyster setting behavior in an effort to understand why oyster populations have not recovered. Studies that have examined setting surfaces suggest that biofilms promote oyster larval settlement; however, similar studies with barnacle larvae have found an inhibitory relationship. The present study utilized field-produced biofilms of different ages to determine if natural biofilms inhibit or promote …

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Genetic Differentiation Of The Parasitoid, Cotesia Congregata (Say), Based On Host-Plant Complex, Georgia Karns Jul 2009

Genetic Differentiation Of The Parasitoid, Cotesia Congregata (Say), Based On Host-Plant Complex, Georgia Karns

Theses and Dissertations

Endoparasitoids of herbivorous lepidopterans have intimate relationships with their host species as well as the plant on which their host develops. Characteristics of both hosts and plants can affect parasitoid success in tri-trophic systems and thus, drive diversification. Genetic differentiation was estimated for Cotesia congregata (Say) collected from two distinct host-plant complexes, Manduca sexta L. on tobacco (Nicotiana tabacum L.) and Ceratomia catalpae, (Haworth) on catalpa (Catalpa bignonioides Walker), in the mid-Atlantic region of North America using seven microsatellite loci and the mitochondrial COI locus. Microsatellite allele frequencies were differentiated based on host-plant complex, and COI haplotypes from individuals on …

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Assessment Of Pre-Pcr Whole Genome Amplification Of Single Pollen Grains Using Flowering Dogwood (Cornus Florida), Candace Dillon Jul 2009

Assessment Of Pre-Pcr Whole Genome Amplification Of Single Pollen Grains Using Flowering Dogwood (Cornus Florida), Candace Dillon

Theses and Dissertations

Studies of gene flow in natural plant populations often focus on either historical or abiotic dispersal methods (e.g. wind, water, gravity), but there is little information available on contemporary, animal-mediated pollen dispersal patterns. Emerging molecular laboratory techniques allow unprecedented insights into spatial patterns of pollen-mediated gene flow. However, to date, technical challenges have limited their widespread application. The genome of a pollen grain can be amplified via whole genome amplification (WGA) prior to traditional amplification via polymerase chain reaction (PCR) to prevent the stochastic effects associated with low copy number amplification. Even still, WGA can suffer from low success rates …

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Understanding The Genetic Consequences Of Rapid Range Expansion: A Case Study Using The Invasive Microstegium Vimineum Trin. (Poaceae), Stephen Baker Jul 2009

Understanding The Genetic Consequences Of Rapid Range Expansion: A Case Study Using The Invasive Microstegium Vimineum Trin. (Poaceae), Stephen Baker

Theses and Dissertations

Global temperature changes are predicted to influence the distributions of plants and can have significant consequences for population genetic structure. Both the nature of these consequences and the processes that shape them are of interest for both conservation genetics and the development of realistic management programs. Rapid range expansion occurs on short temporal scales not conducive to conventional phylogeographical analyses. This paper presents the findings from a population genetic study of the invasive grass Microstegium vimineum Trin. A. Camus throughout the James River Basin of Virginia. Genotypic analysis using Amplified Fragment Length Polymorphism (AFLP) molecular markers were used to test …

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Sexual Selection In A Species With Exploded Leks: The White-Crowned Manakin (Pipra Pipra), Wendy P. Tori Jul 2009

Sexual Selection In A Species With Exploded Leks: The White-Crowned Manakin (Pipra Pipra), Wendy P. Tori

Dissertations

Understanding what determines male reproductive success is central to sexual selection theory. The main goal of this dissertation was to examine the processes that shape female mate choice and male reproductive success in an exploded lek species: the White-crowned Manakin (Pipra pipra). The first chapter examined if females select males with certain genetic characteristics to gain indirect fitness benefits. Specifically, it tested whether females preferentially mate with unrelated males or males with high overall heterozygosity to increase the genetic diversity of their offspring. The second chapter examined if food resources within territories affect male mating success of territory …

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Puf1p-Mediated Mrna Decay And Combinatorial Control Of Mrna Stability By The Yeast Puf Proteins, Randi J. Ulbricht Jul 2009

Puf1p-Mediated Mrna Decay And Combinatorial Control Of Mrna Stability By The Yeast Puf Proteins, Randi J. Ulbricht

Dissertations

The stability of a messenger RNA (mRNA) is a highly regulated and important aspect of gene expression. Proteins that regulate mRNA stability often bind to 3' untranslated region (UTR) sequence elements. The eukaryotic Puf proteins are one class of 3'UTR binding proteins that regulate the stability and expression of their target transcripts. Several global genome analyses have identified hundreds of potential mRNA targets of the Saccharomyces cerevisiae Puf proteins, however only three mRNA targets for these proteins have been characterized thus far. After direct testing of nearly forty candidate mRNAs, I have established three of these as true mRNA targets …

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The Trouble With Transfer, Kathryn Jane Groneman Jul 2009

The Trouble With Transfer, Kathryn Jane Groneman

Theses and Dissertations

It is hoped that the scientific reasoning skills taught in our biology courses will carry over to be applied in novel settings: to new concepts, future courses, other disciplines, and non-academic pursuits. This is the educational concept of transfer. Efforts over many years in the Cell Biology course at BYU to design effective assessment questions that measure competence in both deep understanding of conceptual principles and the ability to draw valid conclusions from experimental data have had at least one disquieting result. The transfer performance of many otherwise capable students is not very satisfactory. In order to explain this unsatisfactory …

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Evolution And Maintenance Of Plumage Polymorphism: The Case Of The Red-Footed Booby (Sula Sula), Patricia Carvalho Baiao Jul 2009

Evolution And Maintenance Of Plumage Polymorphism: The Case Of The Red-Footed Booby (Sula Sula), Patricia Carvalho Baiao

Dissertations

The red-footed booby (Sula sula) is considered one of the most polymorphic seabirds, with three recognized major adult plumage types: (1) white; (2) white-tailed brown; and (3) brown, and several degrees of intermediates. The ratio of these color morphs varies among populations, with the white morph typically predominating. However, there are a few populations that present an inversed ratio of color morphs, such as Isla Europa in the Indian Ocean and the Galapagos archipelago, with the white-tailed brown or brown morphs predominating. I studied natural populations of red-footed boobies from three geographic locations, namely, the Galapagos archipelago, Johnston Atoll in …

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Site- And Species-Specific Patterns Of Metal Bioavailability In Edible Plants, Hollydawn Murray, Karen Thompson, Sheila Macfie Jul 2009

Site- And Species-Specific Patterns Of Metal Bioavailability In Edible Plants, Hollydawn Murray, Karen Thompson, Sheila Macfie

Biology Publications

Differences in metal uptake between plant species and soil types were compared to assess the safe use of mildly contaminated soils for the growth of edible food crops. Accumulation of metals in five plant species grown in each of three field soils and a commercial soil were evaluated in a controlled environment room. Metal bioavailability varied more with plant species than with type of soil. Among a number of physical and chemical soil properties that were determined, high metal content and low percent organic matter were the best predictors of increased metal bioavailability. Contamination levels of metals measured in soil …

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Selective Herbivory By The Desert Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), Monte P. Sanford, Nancy Huntly Jul 2009

Selective Herbivory By The Desert Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), Monte P. Sanford, Nancy Huntly

Biology Faculty Publications

We studied herbivory by the desert woodrat (Neotoma lepida) on Joshua trees (Yucca brevifolia) in the Mojave Desert to determine whether N. lepida fed selectively based on leaf nitrogen content. We measured leaf nitrogen content and the location and amount of herbivory by woodrats on Y. brevifolia trees in southwestern Utah, USA. Neotoma lepida removed the outer tips of leaves (1/3 to 2/3 of total leaf length) but left leaf bases, which had lower nitrogen content, uneaten. Herbivory by N. lepida also was concentrated on rosettes that were oriented south, and these had significantly higher nitrogen …

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An Evaluation Of Bacterial And Fungal Contributions To Organic Matter Decomposition Along A Soil Moisture Gradient, Morgan Rawls Jul 2009

An Evaluation Of Bacterial And Fungal Contributions To Organic Matter Decomposition Along A Soil Moisture Gradient, Morgan Rawls

Theses and Dissertations

The decomposition of plant litter is a critical biological function that aids in nutrient cycling and energy transfers within and between ecosystems. The primary decomposers of dead leaf material are bacteria and fungi, though there is no consensus as to which of these groups is dominant, nor is it known how the abundance and composition of these communities changes over time. The objectives of this study were to examine the relative contributions of bacterial and fungal populations to leaf organic matter (OM) decomposition and to consider the effect of moisture availability on the microbial community. The study was conducted across …

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Co-Occurrence With A Congeneric Species Predicts Life History And Morphological Diversification In The Mexican Livebearing Fish Poelicopsis Baenschi, Laura E. Scott Jul 2009

Co-Occurrence With A Congeneric Species Predicts Life History And Morphological Diversification In The Mexican Livebearing Fish Poelicopsis Baenschi, Laura E. Scott

Theses and Dissertations

Understanding why some species coexist and others do not remains one of the fundamental challenges of ecology. While several lines of evidence suggest that closely related species are unlikely to occupy the same habitat because of competitive exclusion, there are many cases where closely related species do co-occur. Research comparing sympatric and allopatric populations of co-occurring species provides a framework to understand the role of phenotypic diversification in species coexistence. In this study I focus on the livebearing fish Poeciliopsis baenschi and ask if differences in phenotypic traits among populations can be explained by the presence or absence of the …

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A Bac-Based Physical Map Of The Hessian Fly Genome Anchored To Polytene Chromosomes, Rajat Aggarwal, Thiago R. Benatti, Navdeep Gill, Chaoyang Zhao, Ming-Shun Chen, John P. Fellers, Brandon J. Schemerhorn, Jeff J. Stuart Jul 2009

A Bac-Based Physical Map Of The Hessian Fly Genome Anchored To Polytene Chromosomes, Rajat Aggarwal, Thiago R. Benatti, Navdeep Gill, Chaoyang Zhao, Ming-Shun Chen, John P. Fellers, Brandon J. Schemerhorn, Jeff J. Stuart

Biology Faculty Articles

Background: The Hessian fly (Mayetiola destructor) is an important insect pest of wheat. It has tractable genetics, polytene chromosomes, and a small genome (158 Mb). Investigation of the Hessian fly presents excellent opportunities to study plant-insect interactions and the molecular mechanisms underlying genome imprinting and chromosome elimination. A physical map is needed to improve the ability to perform both positional cloning and comparative genomic analyses with the fully sequenced genomes of other dipteran species. Results: An FPC-based genome wide physical map of the Hessian fly was constructed and anchored to the insect's polytene chromosomes. Bacterial artificial chromosome (BAC) clones corresponding …

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Presence Of Haemosporidia And Flaviviruses In Breeding Prothonotary Warblers (Protonotaria Citrea): An Analysis Of Spatial And Temporal Trends In Infection Prevalence And Associations With Reproductive Success, Elena Grillo Jul 2009

Presence Of Haemosporidia And Flaviviruses In Breeding Prothonotary Warblers (Protonotaria Citrea): An Analysis Of Spatial And Temporal Trends In Infection Prevalence And Associations With Reproductive Success, Elena Grillo

Theses and Dissertations

As Neotropical migratory birds, Prothonotary Warblers are exposed to parasites in both tropical and temperate regions and may act as dispersal agents between geographic areas. This study identifies the prevalence of Haemosporidia, West Nile Virus (WNV), and St. Louis Encephalitis virus (SLEV) in this species. A total of 71.6% of captured Prothonotary Warblers were infected with Haemosporidia during the 2008 breeding season, and infection prevalence increased throughout the season. This temporal change in prevalence is likely due to infection relapse and transmission of new infections. No correlations between reproductive effort and infection status were observed, nor were any associations between …

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Heterosternuta Sulphuria (Coloptera: Dytiscidae) Occurence In The Sulphur Springs Headwater System And In Buffalo National River Tributaries (Arkansas, Usa): Current Distribution, Habitat Conditions, And Biomonitoring Framework, S.D. Longing, B.E. Haggard Jul 2009

Heterosternuta Sulphuria (Coloptera: Dytiscidae) Occurence In The Sulphur Springs Headwater System And In Buffalo National River Tributaries (Arkansas, Usa): Current Distribution, Habitat Conditions, And Biomonitoring Framework, S.D. Longing, B.E. Haggard

Arkansas Water Resources Center Technical Reports

Heterosternuta sulphuria is an endemic aquatic species of concern in Arkansas, with a priority score of 80 out of 100 and a conservation rank of S1and G1. A need of the Arkansas Wildlife Action Plan (AWAP) was to obtain baseline information on distribution and population status of H. sulphuria. Here, we report new H. sulphuria records for 39 sites across 10 counties in the Ozark Highlands and Boston Mountain ecoregions and a determined habitat type of shallow margins and small bedrock pools of perennial streams and spring seeps. Few habitat patches were observed per site because detection was typically rapid …

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Assessing Organic Matter Breakdown And Associated Macroinvertebrate Community Structure In Headwater Streams: Effects Of Hydrologic Gradients And Upland Timber Harvesting, Miller Scott Jarrell Jul 2009

Assessing Organic Matter Breakdown And Associated Macroinvertebrate Community Structure In Headwater Streams: Effects Of Hydrologic Gradients And Upland Timber Harvesting, Miller Scott Jarrell

Masters Theses & Specialist Projects

I examined the effects of hydrologic gradients and upland timber harvesting with different streamside management zone widths on yellow-poplar (Liriodendron tulipifera) processing and the associated macroinvertebrate community structure in the Cumberland Plateau ecophysic region, U.S.A. Prior to upland timber harvesting, 5.0 ± 0.1 g yellow-poplar leaf packs were constructed, zip-tied to gutter nails, and placed into 7 perennial and 6 temporary stream reaches with similar physiochemical and geomorphic characteristics. From December 2007 to May 2008, 3–5 leaf packs were collected per reach monthly. I found significant differences in the functional feeding group composition. Temporary reaches contained higher shredder, gathering-collector, predator, …

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A Continent-Wide Clone: Population Genetic Variation Of The Invasive Plant Hieracium Aurantiacum (Orange Hawkweed; Asteraceae) In North America, Eli S. Loomis, Lila Fishman Jul 2009

A Continent-Wide Clone: Population Genetic Variation Of The Invasive Plant Hieracium Aurantiacum (Orange Hawkweed; Asteraceae) In North America, Eli S. Loomis, Lila Fishman

Biological Sciences Faculty Publications

We investigated the population genetic structure of the invasive plant Hieracium aurantiacum (Asteraceae), a facultative apomict. We generated amplified fragment length polymorphism fingerprints for H. aurantiacum samples from across its invasive range in North America (N = 226) and from six other North American native and invasive Hieracium species (N = 60). Almost no genetic variability was found in the North American H. aurantiacum across locations from Alaska and Oregon to Pennsylvania and Ontario (clonal diversity = 0.035). In contrast, other Hieracium species showed a range of clonal diversities (range = 0.154-1.0). The single H. aurantiacum genotype that dominated the …

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Bar-Coded Pyrosequencing Reveals Shared Bacterial Community Properties Along The Temperature Gradients Of Two Alkaline Hot Springs In Yellowstone National Park, Scott R. Miller, Aaron L. Strong, Kenneter L. Jones, Mark C. Ungerer Jul 2009

Bar-Coded Pyrosequencing Reveals Shared Bacterial Community Properties Along The Temperature Gradients Of Two Alkaline Hot Springs In Yellowstone National Park, Scott R. Miller, Aaron L. Strong, Kenneter L. Jones, Mark C. Ungerer

Biological Sciences Faculty Publications

An understanding of how communities are organized is a fundamental goal of ecology but one which has historically been elusive for microbial systems. We used a bar-coded pyrosequencing approach targeting the V3 region of the bacterial small-subunit rRNA gene to address the factors that structure communities along the thermal gradients of two alkaline hot springs in the Lower Geyser Basin of Yellowstone National Park. The filtered data set included a total of nearly 34,000 sequences from 39 environmental samples. Each was assigned to one of 391 operational taxonomic units (OTUs) identified by their unique V3 sequence signatures. Although the two …

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Differential Interactions Of The Catalytic Subunits Of Adenylyl Cyclase With Forskolin Analogs, Cibele Pinto, Melanie Hübner, Andreas Gille, Mark Richter, Tung-Chung Mou, Stephen R. Sprang, Roland Seifert Jul 2009

Differential Interactions Of The Catalytic Subunits Of Adenylyl Cyclase With Forskolin Analogs, Cibele Pinto, Melanie Hübner, Andreas Gille, Mark Richter, Tung-Chung Mou, Stephen R. Sprang, Roland Seifert

Biological Sciences Faculty Publications

The diterpene forskolin (FS) binds to, and activates, mammalian membranous adenylyl cyclase (AC) isoforms I-VIII. Diterpenes without C(1)-OH group do not activate ACs. The C(1)-OH group forms a hydrogen bond with the backbone oxygen of Val506 of the C1 catalytic subunit of AC (isoform V numbering). To better understand the mechanism of AC activation we examined the interactions of FS and eight FS analogs with purified catalytic AC subunits C1 (AC V) and C2 (AC II) by fluorescence spectroscopy, using 2',3'-O-(N-methylanthraniloyl)-guanosine 5'-triphosphate (MANT-GTP) as fluorescent reporter probe, and by enzymatic activity. FS analogs induced C1/C2 assembly as assessed by fluorescence …

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Molluscan Models In Evolutionary Biology: Apple Snails (Gastropoda: Ampullariidae) As A System For Addressing Fundamental Questions, Kenneth Hayes Jul 2009

Molluscan Models In Evolutionary Biology: Apple Snails (Gastropoda: Ampullariidae) As A System For Addressing Fundamental Questions, Kenneth Hayes

Department of Biology Faculty Publications

Molluscs constitute the second largest phylum in terms of the number of described species and possess a wide array of characteristics and adaptations for living in marine, terrestrial, and freshwater habitats. They are morphologically diverse and appear in the fossil record as far back as the early Cambrian (-560 mybp). Despite their high diversity and long evolutionary history, molluscs are often underused as models for the study of general aspects of evolutionary biology. Freshwater snails in the family Ampullariidae have a global tropical and subtropical distribution and high diversity with more than 150 species in nine currently recognized genera, making …

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Was Climate The Prime Releaser For Encephalization? An Editorial Comment, David Schwartzman, George Middendorf, Miranda Armour-Chelu Jul 2009

Was Climate The Prime Releaser For Encephalization? An Editorial Comment, David Schwartzman, George Middendorf, Miranda Armour-Chelu

Department of Biology Faculty Publications

Kleidon (2009) concludes that warm climates impose important constraints on the evolution of large brains relative to body size, confirming our previous hypothesis (Schwartzman and Middendorf 2000). Here we update the case for our hypothesis and present a first approximation estimate of the cooling required for hominin brain size increase using a simple model of heat loss. We conclude that Pleistocene glacial episodes were likely sufficient to serve as prime releasers for emergence of Homo habilis and Homo erectus. In addition, we propose that atmospheric oxygen levels may been an analogous constraint on insect encephalization.

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Environmental Regulation Of Carbon Isotope Discrimination And Internal Co2 Conductance In C3 Leaves, Christopher Paul Bickford Jul 2009

Environmental Regulation Of Carbon Isotope Discrimination And Internal Co2 Conductance In C3 Leaves, Christopher Paul Bickford

Biology ETDs

Stable carbon isotopes are powerful tools for elucidating leaf- and ecosystem- level processes, and recent technological developments provide new opportunities to assess the isotopic flux during leaf gas exchange. In these studies I used a tunable diode laser spectroscope coupled to a infra-red gas analyzer to measure the isotopic composition of leaf gas exchange at high frequency in both field and greenhouse settings and assess environmental regulation of carbon isotope discrimination (Δ) and internal conductance of CO2 to sites of carboxylation (gi). I measured Δ and gi across diurnal and seasonal periods in field-grown Juniperus monosperma trees and used these …

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Description Of Thermonectus Nigrofasciatus And Rhantus Binotatus (Coleoptera:-Dytiscidae) Mating Behavior, Lauren M. Cleavall Jul 2009

Description Of Thermonectus Nigrofasciatus And Rhantus Binotatus (Coleoptera:-Dytiscidae) Mating Behavior, Lauren M. Cleavall

Biology ETDs

Models of sexual conflict predict that diving beetles should respond morphologically and behaviorally during mating events to overcome the opposing sex. Morphological and behavioral adaptations may result from pressures by one sex to overcome resistance to mating attempts of the opposite sex. Morphological data supports an evolutionary arms race in diving beetles (Dytiscidae) exhibited in a series of adaptations attributable to sexual conflict between males and females. Males of certain Dytiscinae have sucker shaped adhesion setae on their front and mid tarsi to improve attachment to the females elytra prior to and during mating, whereas females have evolved grooves, ridges, …

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Transient De-Coupling Of Photosynthesis And Stomatal Conductance In Response To Leaf Primary Vein Cut In Helianthus Annuus, Laura Elizabeth Green Jul 2009

Transient De-Coupling Of Photosynthesis And Stomatal Conductance In Response To Leaf Primary Vein Cut In Helianthus Annuus, Laura Elizabeth Green

Biology ETDs

Control of stomatal aperture is the primary way plants regulate gas exchange in the short-term, but what triggers stomatal responses to water stress is still debated. Chlorophyll-a fluorescence imaging, local leaf temperature, and gas exchange were measured simultaneously following a cut to primary leaf vein of Helianthus annuus to access the effect of local leaf xylem cavitation on leaf function. The treatment was repeated under 3 different vapor pressure deficit (VPD) conditions. Surprisingly, photosynthesis (A) and stomatal conductance (gs) responded inversely immediately following the treatment, indicating that A was not CO2 limited by stomatal closure. Comparisons of fluorescence images and …

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Taxonomic Revision And Phylogenetic Analysis Of The Genus Elytroleptus (Dugés) (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini), Traci Lee Grzymala Jul 2009

Taxonomic Revision And Phylogenetic Analysis Of The Genus Elytroleptus (Dugés) (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini), Traci Lee Grzymala

Biology ETDs

The longhorned beetle genus Elytroleptus (Dugés) (Cerambycidae:Cerambycinae: Trachyderini) is revised to include fifteen species. One new species is described: E. quadricostatus sp.n. (Grzymala & Miller). Three new synonymies are proposed: E. dichromaticus (Linsley, 1961) = E. divisus (LeConte, 1884) syn. n.; E. luteicollis (Skiles & Chemsak, 1982) = E. ignitus (LeConte, 1884) syn. n.; E. peninsularis (Hovore, 1988) = E. immaculipennis (Knull, 1935) syn. n. The genus is generally distributed throughout the southwestern United States, Mexico, and Central America (Guatemala, Honduras, and Nicaragua) with one species extending the range to the north and southeastern United States. The genus is of …

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Mojave Applied Ecology Notes Summer 2009, Kevin E. Oliver, Dianne N. Bangle, E. Cayenne Engel, Lindsay P. Chiquoine, Scott R. Abella Jul 2009

Mojave Applied Ecology Notes Summer 2009, Kevin E. Oliver, Dianne N. Bangle, E. Cayenne Engel, Lindsay P. Chiquoine, Scott R. Abella

Mojave Applied Ecology Notes

BLM and wildfire protection in the Mojave, studies of the sticky ringstem flowering phenology in Lake Mead NRA, restoration work within gypsum soils, post-fire response synthesis for Mojave and Sonoran deserts

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Drosophila Risc Component Vig And Its Homolog Vig2 Impact Heterochromatin Formation, Elena Gracheva, Monica Dus, Sarah C.R. Elgin Jul 2009

Drosophila Risc Component Vig And Its Homolog Vig2 Impact Heterochromatin Formation, Elena Gracheva, Monica Dus, Sarah C.R. Elgin

Biology Faculty Research

Heterochromatin formation plays an important role in gene regulation and the maintenance of genome integrity. Here we present results from a study of the D. melanogaster gene vig, encoding an RNAi complex component and its homolog vig2 (CG11844) that support their involvement in heterochromatin formation and/or maintenance. Protein null mutations vig(EP812) and vig2(PL470) act as modifiers of Position Effect Variegation (PEV). VIG and Vig2 are present in polytene chromosomes and partially overlap with HP1. Quantitative immunoblots show depletion of HP1 and HP2 (large isoform) in isolated nuclei from the vig(EP812) mutant. The vig2(PL470) mutant strain demonstrates a decreased level of …

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