Life Sciences Commons^™

The Family Fuselloviridae : Diversity And Replication Of A Hyperthermic Virus Infecting The Archaeon Genus Sulfolobus, Adam Joseph Clore

Dissertations and Theses

The virus family Fuselloviridae infects the hyperthermophilic and acidophilic Crenarchaeon genus Sulfolobus and has been isolated from terrestrial hotsprings worldwide. Two previously uncharacterized Fuselloviruses, SSV-13 and SSV-L1, were isolated and sequenced and are compared to the five fully sequenced viruses presently in the public databases. Conserved promoters in all viruses and similar putative origins of replication suggest that these viruses use a transcriptional and genomic replication program similar to the relatively well-characterized SSV1. Pairwise comparisons of conserved genes in the seven virus genomes show that, like its host Sulfolobus, these viruses' genetic divergence correlates with geographic separation. Genome rearrangements, horizontal …

Registered Dietitian Dress And The Effect Of Dietitian Dress On Perceived Professionalism, Connie Lynn Packer

Theses and Dissertations

People use others' dress to make assumptions, including how they believe the wearer will behave. Observers then adjust their behavior in response to the anticipated behavior of the wearer. Physician or nurse dress affects the degree to which patients perceive the medical professional as confident, experienced, competent, mature, trustworthy, and professional. Dietitian dress has not been studied. Our purpose was to identify 1) the current level of formality of dress of registered dietitians (RD), 2) characteristics of dress codes, 3) the effect of RD dress on patient/client perceptions of professional traits, and 4) the level of formality at which an …

The Role Of Carcinine In Signaling At The Drosophila Photoreceptor Synapse, Brendan A. Gavin, Susan E. Arruda, Patrick J. Dolph

Dartmouth Scholarship

The Drosophila melanogaster photoreceptor cell has long served as a model system for researchers focusing on how animal sensory neurons receive information from their surroundings and translate this information into chemical and electrical messages. Electroretinograph (ERG) analysis of Drosophila mutants has helped to elucidate some of the genes involved in the visual transduction pathway downstream of the photoreceptor cell, and it is now clear that photoreceptor cell signaling is dependent upon the proper release and recycling of the neurotransmitter histamine. While the neurotransmitter transporters responsible for clearing histamine, and its metabolite carcinine, from the synaptic cleft have remained unknown, a …

In-Vitro Investigations On Ultrasonic Control Of Water Chestnut, Meiyin S Wu, J. Wu

Department of Biology Faculty Scholarship and Creative Works

Water chestnut (Trapa natans L.) is native to southern Europe and tropical Africa and Asia and was first introduced into North America in 1874. Since then, wild populations have quickly become established in many locations in the northeastern United States. T. natans is referred to as a noxious aquatic weed since its aggressive growth usually results in complete coverage of the water surface with floating rosettes of leaves. This study investigated the potential of the ultrasonic control of water chestnut since ultrasound has been documented to effectively damage plant cells and tissues. Various frequencies and amplitudes of ultrasound waves generated …

Predicting The Growth Of Deciduous Tree Species In Response To Water Stress: Fvs-Bgc Model Parameterization, Application And Evaluation, Ying Wang

All Theses

A hybrid model (FVS-BGC) that couples the process-model STAND-BGC to the empirically based forest vegetation simulator (FVS) was parameterized with comprehensive ecophysiological, site, and silvicultural data collected on Acer rubrum L. (A. rubrum), Paulownia elongata (P. elongata), Quercus nuttallii (Q. nuttallii), and Quercus phellos (Q. phellos) in 2006. A series of simulations provided of estimates species-specific carbon gain, growth, and yield under well-watered and water-stressed conditions. Simulations on a species-specific basis allowed assessment of drought effects on stand production and the ability of FVS-BGC to predict on a deciduous species basis. Under well watered conditions, FVS-BGC was able to predict …

Effects Of Endurance Training On The Ampk Response To Exercise., David Gerald Chesser

Theses and Dissertations

Activation of AMP-activated protein kinase (AMPK) results in the upregulation of several intracellular systems which help to prepare a cell for a high energy challenge. The magnitude of the AMPK response to a 10 min bout of exercise has been found to decrease in red quadriceps (RQ) following training, while putative AMPK roles seem to be maintained; specifically, the biogenesis of mitochondria and higher levels of hexokinase II and glucose transporter 4 (GLUT4). If the AMPK response to exercise is responsible in part for these adaptations, how can they be maintained if the AMPK response is attenuated? The purpose of …

The Effect Of Febrile Temperature On Plasmodium Falciparum, Heidi Sue Porter

Theses and Dissertations

Previously it has been shown that cultures of Plasmodium falciparum died following exposure to a febrile temperature of 40°C, as demonstrated by a decrease in parasitemia of the following generation. In the current study, the effect of 40°C treatment on culture media, erythrocytes, and parasite glucose consumption, were ruled out as possible influences on parasite death, demonstrating that 40°C impacted the parasites directly. Metabolic profiling of DNA synthesis, protein synthesis, and glucose utilization during exposure to 40°C clearly indicated that febrile temperatures had direct effect on major metabolic pathways and parasite development, beginning 20-24 hr after erythrocyte invasion. The ring …

Use Of Near-Infrared Spectroscopy For Qualitative And Quantitative Analyses Of Grains And Cereal Products, Panjama Cheewapramong

Department of Food Science and Technology: Dissertations, Theses, and Student Research

The purpose of the first part of the study was to develop a simplified near-infrared reflectance (NIR) spectroscopy method for detecting insect larvae in individual wheat kernels. Discriminant analysis, based on Mahalanobis distances calculated from log 1/R data at only four discrete wavelengths, yielded better results for classification of sound and insect infested wheat kernels than principal component analysis (PCA) using the spectral region from 1100 to 1900 nm. This simplified technique was then used to detect 3- and 4-week-old larvae of granary and maize weevils in wheat kernels. A model developed from a calibration set containing sound kernels and …

Small Grains And Field Peas: 2008 Variety Recommendations (2007 Crop Performance Results), Cooperative Extension Service, South Dakota State University

SDSU Extension Circulars

Variety selection is a fundamental element in a sound crop production program. This report contains variety recommendations, descriptions, and yield data for the spring-seeded small grains – hard red spring wheat, oat, and barley, along with the fall-seeded small grain –hard red winter wheat. Key factors in variety selection include yield, yield stability, maturity, straw strength, height, test weight, quality, and disease resistance. Yield is an important factor; however, a variety with good disease resistance, straw strength, and high grain quality may be more profitable in some cases than the highest yielding variety. Disease resistance information is based on reactions …

Drosophila Melanogaster Starvation Resistance: A Quantitative Genetic And Physiological Investigation In Relationship To Life History Traits, Mei-Hui Wang

School of Biological Sciences: Dissertations, Theses, and Student Research

Starvation resistance is an important trait for insect survival. The studies presented in this dissertation investigated starvation resistance using Drosophila melanogaster in terms of genetic correlations, physiological mechanisms and evolutionary trajectory.
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/="/"> Whether increase of starvation resistance can also extend lifespan is a controversial issue in D. melanogaster. Quantitative trait locus (QTL) mapping can provide good evidence concerning this controversial problem. A QTL analysis was conducted to test the correlation between starvation resistance and longevity using a set of recombination inbred lines (RILs) from a natural population of D. melanogaster. We found the QTL effects were consistent for …

Vertex Clustering In Random Graphs Via Reversible Jump Markov Chain Monte Carlo, Stefano Monni, Hongzhe Li

UPenn Biostatistics Working Papers

Networks are a natural and effective tool to study relational data, in which observations are collected on pairs of units. The units are represented by nodes and their relations by edges. In biology, for example, proteins and their interactions, and, in social science, people and inter-personal relations may be the nodes and the edges of the network. In this paper we address the question of clustering vertices in networks, as a way to uncover homogeneity patterns in data that enjoy a network representation. We use a mixture model for random graphs and propose a reversible jump Markov chain Monte Carlo …

Calcium Dynamics Affecting Egg Production, Skeletal Integrity, And Egg Coloration In Ring-Necked Pheasants (Phasianus Colchicus), Landon R. Jones

Theses and Dissertations

These 4 chapters represent manuscripts formatted for submission to journals based on an experiment conducted on Ring-necked Pheasants (Phasianus colchicus). Calcium limits the distribution of this species, which produces 7-15 eggs per clutch. They may renest up to 5 times per breeding season on a diet low in calcium. The first chapter examines egg production in laying hens on 7 different diets from 0.19-4.47% calcium in the absence of calcium loading. Calcium-loaded pheasants store calcium in medullary bone before an experiment and can draw on this surplus during egg production, possibly skewing experimental results. We measured egg production, egg characteristics, …

Reconstructing Twentieth-Century Sea Surface Temperature Variability In The Southwest Pacific: A Replication Study Using Multiple Coral Sr/Ca Records From New Caledonia, Kristine L. Delong, Terrence M. Quinn, Frederick W. Taylor

Marine Science Faculty Publications

Coral‐based climate reconstructions typically have not used multiple cores from a region to capture and replicate a climate signal largely because of concerns of coral conservation, analytical expense, and time constraints. Coral Sr/Ca reproducibility through the twentieth century was investigated using three intracolony and three intercolony coral records from the reefs offshore of Amédée Island, New Caledonia. Different sampling resolutions were examined in coral Sr/Ca (fortnightly and monthly) and δ¹⁸O (fortnightly, monthly, and seasonally) as well as similar scale subsampling of the daily in situ sea surface temperature (SST) record. The mean coral Sr/Ca, δ¹⁸O, and …

Phylogeography Of The Livebearer Xenophallus Umbratilis (Teleostei: Poeciliidae): Glacial Cycles And Sea Level Change Predict Diversification Of A Freshwater Tropical Fish, Carissa Poole Jones

Theses and Dissertations

The biogeography of Central America is considered a classical case study in understanding the impact of vicariant events on patterns of biotic dispersal. While many biogeographers have focused on community composition and geographic limits of species at broad scales across Central America, much less work has focused on post-colonization diversification patterns at finer scales. The livebearing freshwater fish Xenophallus umbratilis presents an ideal system for determining the impact of recent earth history events on biodiversity in northern Costa Rica. Here, we test the hypothesis that marine inundation of the San Carlos and Northern Limón basins during the Miocene has caused …

A Study Of Habitat Variables Associated With Northern Goshawk Nest Site Activity On The Three National Forests In Southern Utah, Keeli Shea Marvel

Theses and Dissertations

The Northern Goshawk has been a species of concern since its decline in the early 1990s, which has been attributed in part to loss of critical breeding and wintering habitat. Nest site selection of goshawks has been correlated with certain specific site characteristics including, but not limited to, forest species composition, forest stand size, diameter of nest tree, percent cover, tree height, site slope, and aspect. The goshawk holds the status of a Management Indicator Species (MIS) on all of the six national forests in Utah. This status requires annual monitoring to track goshawk numbers and to address any activities …

Beneficial Fungal Interactions Resulting In Accelerated Germination Of Astragalus Utahensis, A Hard-Seeded Legume, Sean D. Eldredge

Theses and Dissertations

Seed germination is pivotal in the life cycle of native plants in a restorative context because initiation of the metabolic processes critical to establishment is key to survival in such a competitive environment. Dormancy characteristics of some native plants including the subject species, Astragalus utahensis, have evolved mechanisms to control germination in order to maintain a seed bank and ensure germination at the right time under optimal conditions. In vitro germination studies confirm beneficial interactions between Alternaria and Aspergillus fungi and Astragalus utahensis seed. Inoculated seed trials (1.0 x 106 spores/mL) exhibited a highly significant difference in percent germination between …

Light-Evoked Calcium Responses Of Isolated Melanopsin- Expressing Retinal Ganglion Cells, Andrew T. E. Hartwick, Jayne R. Bramley, Jianing Yu, Kelly T. Stevens, Charles N. Allen, William H. Baldridge, Patricia J. Sollars, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

A small number (<2%) of mammalian retinal ganglion cells express the photopigment melanopsin and are intrinsically photosensitive (ipRGCs). Light depolarizes ipRGCs and increases intracellular calcium levels ( [Ca²⁺]_i ) but the signaling cascades underlying these responses have yet to be elucidated. To facilitate physiological studies on these rare photoreceptors, highly enriched ipRGC cultures from neonatal rats were generated using anti-melanopsin-mediated plate adhesion (immunopanning). This novel approach enabled experiments on isolated ipRGCs, eliminating the potential confounding influence of rod/cone-driven input. Light induced a rise in [Ca²⁺]_i (monitored using fura-2 imaging) in the immunopanned ipRGCs and the source of this Ca²⁺ signal was investigated. The Ca²⁺ responses were inhibited by 2-aminoethoxydiphenyl borate, SKF-96365 (1–2-(4-methoxyphenyl)-2-[3-(4-methoxyphenyl)propoxy]ethyl-1H-imidazole), flufenamic acid, …

Using Scissors To Quantify Hardness Of Insects: Do Bats Select For Size Or Hardness?, Patricia W. Freeman, Cliff A. Lemen

University of Nebraska State Museum: Mammalogy Papers

Scissors are used to determine the hardness of fresh insects of different size and taxa. Our results indicate a strong relationship between the size of an insect and its hardness, which can be expressed as log(F_max) = 0.65 × log(V) + α. F_max is the maximal force needed to cut the insect and is our measure of insect hardness. V is the volume of the insect and α is a constant that can be derived for different insect taxa. The value of 0.65 was found as an average of beetle and moth samples, and this …

A Quantitative Synthesis Of The Medicinal Ethnobotany Of The Malinké Of Mali And The Asháninka Of Peru, With A New Theoretical Framework, Nathaniel Bletter

Publications and Research

Background: Although ethnomedically and taxonomically guided searches for new medicinal plants can improve the percentage of plants found containing active compounds when compared to random sampling, ethnobotany has fulfilled little of its promise in the last few decades to deliver a bounty of new, laboratory-proven medicinal plants and compounds. It is quite difficult to test, isolate, and elucidate the structure and mechanism of compounds from the plethora of new medicinal plant uses described each year with limited laboratory time and resources and the high cost of clinical trials of new drug candidates.

Methods: A new quantitative theoretical framework of mathematical …

Maestra2: A Model For Simulating Spatially Explicit Carbon Dioxide Exchange Rates Among Species' Water Stress Response, Robert Reynolds

All Theses

MAESTRA2, a species specific mechanistic model, was parameterized to estimate water use, carbon accumulation and organ specific respiration of five deciduous tree species under both irrigated and water stressed conditions. The model was validated using temporally and spatially explicit ecophysiological data to account for seasonal changes in species physiology. The following tree species: Acer rubrum L. 'Summer Red' (A. rubrum), Betula nigra (B. nigra), Paulownia elongata (P. elongata), Quercus nuttallii (Q. nuttallii), and Quercus phellos (Q. phellos) were intensively measured and organ specific destructively harvested samples were compared to modeled estimates of carbon accumulation. Among species, we observed variability in …

The Role Of Secreted Phosphoprotein-24 In Osteoblast Differentiation And Matrix Mineralization, Samuel Ramage

Theses and Dissertations

Secreted Phosphoprotein-24 (Spp24) was initially isolated and characterized as a component of bovine cortical bone matrix. Subsequent characterization has shown it is multiply phosphorylated and homologous to cystatin and TGF-β receptor type II. Spp24 is a minor component of the serum fetuin mineral complex that binds calcium-phosphate minerals and prevents their deposition. The TGF-β receptor homology domain binds BMP-2 weakly in vitro and enhances BMP-2’s osteogenic effects in vivo. The ability of Spp24 to affect BMP activity suggests an important role for Spp24 as a native, bioactive componentof bone that regulates bone development.

Spp24 was highly up-regulated in rat cortical …

Niche Separation Along Environmental Gradients As A Mechanism To Promote The Coexistence Of Native And Invasive Species, Edmund R. Priddis

Theses and Dissertations

Niche separation may be the key to promoting the long-term coexistence of introduced and native species. Physical alterations to the environment (habitat manipulation) or re-introducing native species to former habitats can exploit the maladapted traits of introduced species to create a refuge for native species. No two species have identical niches because evolutionary constraints differ between species with different evolutionary histories. Our objectives were to determine if cold temperatures could promote coexistence between native least chub and introduced western mosquitofish. We used individual scale and population scale experiments to test four hypotheses: 1) colder temperatures would reduce the aggressive behavior …

Effects Of Water Vapor On The Kinetics Of The Methylperoxy Radical Self-Reaction And Reaction With Hydroperoxy, Alecia Mower

Theses and Dissertations

The gas phase reactions of CH3O2 + CH3O2, HO2 + HO2, and CH3O2 + HO2 in the presence of water vapor have been studied at temperatures between 263 and 303 K using laser flash photolysis coupled with UV time-resolved absorption detection at 220 nm and 260 nm. Water vapor concentration was quantified using tunable diode laser spectroscopy operating in the mid-IR. The HO2 self-reaction rate constant is significantly enhanced by water vapor, consistent with what others have reported, whereas CH3O2 self-reaction and the cross-reaction (CH3O2 + HO2) rate constants are nearly unaffected. The enhancement in the HO2 self-reaction rate coefficient …

Songs Of The Wild: Temporal And Geographical Distinctions In The Acoustic Properties Of The Songs Of The Yellow-Breasted Chat, Jackie L. Canterbury

Department of Animal Science: Dissertations, Theses, and Student Research

The Yellow-breasted Chat, Icteria virens, is a member of the wood-warbler family, Parulidae, and exists as eastern I. v. virens and western I. v. auricollis subspecies. It is the only wood-warbler known to sing diurnally and nocturnally.

One objective was to determine whether the eastern and western subspecies produce songs that differ acoustically; another was to determine whether a western population of Chats in Nebraska produces songs that differ acoustically at dawn and at night. Properties measured were maximum frequency, maximum power, notes/second, singing rate, and % time singing. In addition, the inter-song interval and % whistle notes were measured …

Neuronal And Molecular Adaptations Of Gaba Neurons In The Ventral Tegmental Area To Chronic Alcohol, Kimberly Hales

Theses and Dissertations

The purpose of this thesis project was to examine the effects of chronic alcohol on the excitability and molecular adaptation of GABA neurons of the ventral tegmental area (VTA). GABA neurons are of interest with regards to ethanol intoxication, reinforcement, and dependence due to their widespread distribution and connectivity to mesocorticolimbic dopamine (DA) neurons implicated in alcohol reward and addiction. Since we have previously shown adaptation of VTA GABA neuron firing rate to chronic ethanol (Gallegos, Criado et al. 1999) and suppression of gap-junction (GJ) mediated coupling between these neurons by acute ethanol (Stobbs, Ohran et al. 2004), we wanted …

Prevention Of Staphylococcus Epidermidis Biofilm Formation Using A Low-Temperature Processed Silver-Doped Phenyltriethoxysilane Sol–Gel Coating, Niall Stobie, Brendan Duffy, Declan Mccormack, John Colreavy, Martha Hidalgo, Patrick Mchale, Steven Hinder

Articles

Sol–gel coatings which elute bioactive silver ions are presented as a potential solution to the problem of biofilm formation on indwelling surfaces. There is evidence that high-temperature processing of such materials can lead to diffusion of silver away from the coating surface, reducing the amount of available silver. In this study, we report the biofilm inhibition of a Staphylococcus epidermidis biofilm using a low-temperature processed silver-doped phenyltriethoxysilane sol–gel coating. The incorporation of a silver salt into a sol–gel matrix resulted in an initial high release of silver in de-ionised water and physiological buffered saline (PBS), followed by a lower sustained …

The Effect Of Selection For Desiccation Resistance On Cold Tolerance Of Drosophila Melanogaster, Brent J. Sinclair, Sean Nelson, Theresa L. Nilson, Stephen P. Roberts, Allen G. Gibbs

Biological Sciences Faculty Research & Creative Works

Low Temperature and Desiccation Stress Are Thought to Be Mechanistically Similar in Insects, and Several Studies Indicate that There is a Degree of Cross-Tolerance between Them, such that Increased Cold Tolerance Results in Greater Desiccation Tolerance and Vice Versa. This Assertion is Tested at an Evolutionary Scale by Examining Basal Cold Tolerance, Rapid Cold-Hardening (RCH) and Chill Coma Recovery in Replicate Populations of Drosophila Melanogaster Selected for Desiccation Resistance (With Controls for Both Selection and Concomitant Starvation) for over 50 Generations. All of the Populations Display a RCH Response, and There is No Effect of Selection Regime on RCH or …

Nebraska Promotes Sorghum And Pearl Millet Food Processing In East Africa, Intsormil

INTSORMIL Impacts and Bulletins

Sorghum and millet are ideal crops for many parts of Africa. However, sorghum and millet’s use as food sources for large urban populations in West Africa is hampered by 1) lack of infrastructure for conveying and demonstrating the food value of sorghum and millet to small business investors, 2) limitations on the supply of high quality grains to processors, 3) lack of small processors, 4) lack of educational resources related to small business development, 5) lack of product development expertise, and 6) lack of knowledge of evidence supporting nutritional claims associated with sorghum and millet consumption.

The Department of Food …

A Regulator Of Dscam Mutually Exclusive Splicing Fidelity, Sara Olson, Yiannis Savva, Jung Park, Brenton R. Graveley

UCHC Articles - Research

The Down syndrome cell adhesion molecule (Dscam) gene has essential roles in neural wiring and pathogen recognition in Drosophila melanogaster. Dscam encodes 38,016 distinct isoforms via extensive alternative splicing. The 95 alternative exons in Dscam are organized into clusters that are spliced in a mutually exclusive manner. The exon 6 cluster contains 48 variable exons and uses a complex system of competing RNA structures to ensure that only one variable exon is included. Here we show that the heterogeneous nuclear ribonucleoprotein hrp36 acts specifically within, and throughout, the exon 6 cluster to prevent the inclusion of multiple exons. Moreover, hrp36 …

Effects Of An Inserted Endoscope On Chyme Movement In Small Intestine – A Theoretical Model, V. P. Srivastava

Applications and Applied Mathematics: An International Journal (AAM)

The effects of an inserted endoscope on chyme movement in small intestine (gastrointestinal tract) have been investigated. The flow of chyme is induced by a progressive wave of area contraction along the length of intestinal wall under long wavelength approximation. It is found that the chyme movement is significantly influenced due to the presence of the endoscope. The pressure drop assumes lower values for higher values of the endoscope radius for small flow rates but the property reverses with increasing flow rates. The friction forces at intestinal wall and endoscope possess character similar to the pressure drop for any given …