Life Sciences Commons^™

Ecotypic Variation In Elymus Elymoides Subspecies Brevifolius Race C In The Northern Intermountain West, Matthew C. Parsons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Little information is available on the extent of local adaptation for many native grass species. This is the case for squirreltail (Elymus section Sitanion), despite this group's prevalence and importance in rangeland restoration efforts. I evaluated 32 populations of E. elymoides ssp. brevifolius race C, a phylogenetic subdivision of bottlebrush squirreltail (E. elymoides) centered in the northern Intermountain West, for phenotypic variables and neutral genetic markers to measure their association with geographical origin. Phenotypic traits were measured in common field and greenhouse environments, and genetic diversity was assessed using Amplified Fragment Length Polymorphism. Three factors were extracted from the phenotypic …

A Conceptual Framework For Understanding Effects Of Wildlife Water Developments In The Western United States, Randy T. Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Free water can be a limiting factor to wildlife in arid regions of the world. In the western United States, management agencies have installed numerous, expensive wildlife water developments (e.g. catchments, guzzlers, wells) to: 1) increase the distribution or density of target species, 2) influence animal movements, and 3) mitigate for the loss of available free water. Despite over 50 years as an active management practice, water developments have become controversial for several species. We lack an integrated understanding of the ways free water influences animal populations. In particular, we have not meshed understanding of evolutionary adaptations that reduce the …

Mechanisms Of Nutrition Bar Hardening: Effect Of Hydrolyzed Whey Protein And Carbohydrate Source, Shaun P. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of increasing hydrolyzed protein content on the microstructure and hardness of high protein nutrition bars was investigated to determine the mechanism of hardening during storage. Bars with various hydrolyzed protein levels were manufactured using differing ratios of 0, 25, 50, 75, 100% (wt. /wt.) of partially hydrolyzed whey protein isolate (HWPI) to an intact (non-hydrolyzed) whey protein isolate (WPI) which made up approximately 38% of the total bar composition. High fructose corn syrup (HFCS) (42%) and vegetable shortening (20%) constituted the rest of the ingredients. Accelerated aging was performed by storing bars at 32 ^oC for 36 …

Phenotypic Plasticity And The Post-Modern Synthesis: Integrating Evo-Devo And Quantitative Genetics In Theoretical And Empirical Studies, Alison G. Scoville

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mainstream evolutionary biology lacks a mature theory of phenotype. Following from the Modern Synthesis, researchers tend to assume an unrealistically simple mapping of genotype to phenotype, or else trust that the complexities of developmental architecture can be adequately captured by measuring trait variances and covariances. In contrast, the growing field of evolutionary developmental biology (evo-devo) explicitly examines the relationship between developmental architecture and evolutionary change, but lacks a rigorous quantitative and predictive framework. In my dissertation, I strive to integrate quantitative genetics and evo-devo, using both theoretical and empirical studies of plasticity. My first paper explores the effect of realistic …

Synthesis And Characterization Of Lactose-Amines With Respect To Oil-In-Water Emulsion Stability, Nidhi Garg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fatty amines (hexadecyl-amine) can be esterified to lactose via Schiff-base formation at temperatures of 60° C. Extending the time of the reaction results in a darker colored product due to the Maillard reaction. Due to the amphiphilic properties of the lactose-amines, the emulsion stabilization characteristics were investigated.

In this study, synthesis of lactose-amines was done at four different heating and cooling cycles from 4 to 24 hours. Lactose-amines processed for 24 hours and 12 hours of constant heating and cooling cycles are named as 24H and 12H, respectively. Lactose-amines 4H and 8H were processed for 4 and 8 hours of …

Soil Moisture Responses In Traditional And Drought Adapted Landscapes In The Intermountain West, James Gregory

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water conservation in the Intermountain West will be an important issue in the future as population and demand for limited water resources increases. In Utah, outdoor water use accounts for up to 60% of total per capita water use with 67% of that outdoor water being used to irrigate non native plant species to maintain a uniform green appearance. The objective of this study was to measure intra landscape changes in soil water potential during a 21.5 day dry down from DOY 215 to 236.5 in the summer of 2005 and 2006. Four, 2 x 2 replicated traditional and drought …

Disturbance As Restoration In The Intermountain Sagebrush Steppe: Effects On Non Target Bird Species, Russell Edward Norvell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes in shrubsteppe passerine bird habitat associations in response to disturbance were investigated at multiple temporal and spatial scales. Spatial measures incorporated the effects of area at different ecological scales (nest site, territory, and landscape) to include ecologically meaningful extents. Temporal measures included seasonal and annual effects, and were designed to detect lagged responses should they occur. Local-to-landscape scale effects of mechanical restoration treatments on local extirpation and abundances of nine species indicated most were insensitive to changes in habitat quality, while abundance models showed only broad declines. Changing the availability of nesting habitat on both the attractiveness and quality …

Evaluation Of Competition Between Turfgrass And Trees In The Landscape, Christopher A. Hendrickson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population growth in regions of the Intermountain West has resulted in rapid growth of residential neighborhoods. In Utah, the landscapes associated with these expanding neighborhoods consume vast quantities of treated water. This is a concern in all states of the Intermountain West, as water becomes increasingly scarce. Traditionally used turfgrasses, trees and other plants in Intermountain West landscapes require significant amounts of supplemental water considering the intense sunlight, dry winds and sparse rainfall typical of the region. Characterizing the interactions between turfgrass and tree species in these landscapes can aid in the identification of candidate species that consume less nutritional …

Buccal Bone Changes Following Rapid Maxillary Expansion (Rmf), Long-Term Results, Elena S. Iacob

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to use Cone Beam Computed Tomography (CBCT) images to quantitatively evaluate buccal bone changes of maxillary first premolar (P1), second premolar (P2) and first molar (M1) shortly after Rapid Maxillary Expansion (RME) and at the end of orthodontic treatment, as well as to evaluate the variables that may be associated with the short-term and long-term changes. Forty-seven consecutive patients (25 males and 22 females) with a mean age of 14.5years and who required RME as part of their orthodontic treatment and had pre-RME (T1) and post-RME (T2) CBCT images available were used for the …

Macroalgae And Eelgrass Mapping In Great Bay Estuary Using Aisa Hyperspectral Imagery, Shachak Pe'eri, J. Ru Morrison, Frederick T. Short, Arthur C. Mathieson, Anna Brook, Philip Trowbridge

PREP Reports & Publications

Increase in nitrogen concentration and declining eelgrass beds in Great Bay Estuary have been observed in the last decades. These two parameters are clear indicators of the impending problems for NH’s estuaries. The NH Department of Environmental Services (DES) in collaboration with the New Hampshire Estuaries Project (NHEP) adopted the assumption that eelgrass survival can be used as the water quality target for nutrient criteria development for NH’s estuaries. One of the hypotheses put forward regarding eelgrass decline is that a possible eutrophication response to nutrient increases in the Great Bay Estuary has been the proliferation of nuisance macroalgae, which …

Restoration Of Oyster (Crassostrea Virginica) Habitat For Multiple Estuarine Species Benefits, Shachak Pe'eri, J. Ru Morrison, Frederick T. Short, Arthur C. Mathieson, Anna Brook, Philip Trowbridge

PREP Reports & Publications

Increase in nitrogen concentration and declining eelgrass beds in Great Bay Estuary have been observed in the last decades. These two parameters are clear indicators of the impending problems for NH’s estuaries. The NH Department of Environmental Services (DES) in collaboration with the New Hampshire Estuaries Project (NHEP) adopted the assumption that eelgrass survival can be used as the water quality target for nutrient criteria development for NH’s estuaries. One of the hypotheses put forward regarding eelgrass decline is that a possible eutrophication response to nutrient increases in the Great Bay Estuary has been the proliferation of nuisance macroalgae, which …

The Performance Of Maize Crop During Acid Amelioration With Organic Residues In Soils Of Mtwara, Tanzania, Ae Majule, Jo Omollo

Tanzania Journal of Science

This study evaluated acid ameliorative potential and their effects on maize growth of four organic residues namely wild spikenard, cordia, cowpea and pigeon peas through incubations with or without sulphur. This was done in order to recommend potential organic residue source that could ameliorate soil acidity associated with sulphur dusting. Increased levels of sulphur in the soils reduced the growth and dry matter yields of maize due to intense acidification while maize growth and dry matter yields in soils which organic residues were incorporated was enhanced. Enhancement in maize performance may be a result of reduced soil acidity due to …

Involvement Of Methyltransferases Enzymes During The Energy Metabolism Of The Anaerobic Archaeon Methanosarcina Semesiae Sp. Nov., Tj Lyimo

Tanzania Journal of Science

The methyl group transfer from dimethylsulfide (DMS), trimethylamine and methanol to 2-mercaptoethanesulfonic acid (coenzyme M) were investigated from cell extracts of Methanosarcina semesiae sp. nov. to evaluate whether the enzyme systems involved were constitutive or inductive. The extracts from cells grown on DMS exhibited methanogenic activity exclusively with DMS and methanethiol. Likewise when cells were pre-grown on trimethylamine or methanol the extracts only produced methane from the respective metaboilic substrate. Dimethylsulfide:methyl-coenzyme M transferase activity was dependent on ATP, but hydrogen did not stimulate activity. The fact that ATP could be replaced by the reductant Ti(III)-citrate indicates that reductive activation of …

Delineating The Jurassic To Mid Cretaceous Part Of The Pacific Apparent Polar Wander Path, Dcp Masalu

Tanzania Journal of Science

The Jurassic to Mid-Cretaceous apparent polar wander path of the Pacific plate irrespective of ages have been delineated. Two poles have been established: one pole, which is relatively older than the other, is at 75.01°N/287.5°E (α = 6.9°) and the other pole is at  61.0°N°/304.7°E (!95 = 4.5°). These results indicate that the Pacific plate drifted southward during the Jurassic to Early-Cretaceous period. Additionally, the results demonstrate that there is an apparent consistent correspondence between changes of plate motion and significant shifts of the Jurassic to Mid-Cretaceous apparent polar wander path

Occurrence Of Digenean Larvae In Freshwater Snails In The Ruvu Basin, Tanzania, G. Nkwengulila, E. S. P. Kigadye

Tanzania Journal of Science

A survey was carried out on digenean larvae infecting freshwater snails in five habitats in Dar es Salaam, Ruvu and Morogoro. 9424 snails belonging to 12 species from five families were examined for digenean infection from July 1996 – June 1997. 20 morphologically distinguishable cercariae were recovered. Multiple infections were not recorded. While the general prevalence of digeneans in snails was low (3.5%), variations occurred between seasons, among habitats and snail host species. Prevalence was high during the dry season but low in the rain season. Among habitats, highest prevalence was recorded at Kinondoni pond and lowest at Ruvu ponds, …

Abundance And Diversity Of Seagrass And Macrofauna In The Intertidal Areas With And Without Seaweed Farming Activities In The East Coast Of Zanzibar, Thomas J Lyimo, Esther F Mvungi, Yunus D Mgaya

Tanzania Journal of Science

The diversity and abundance of seagrass and associated macrofauna were studied in transects with and without seaweed farms at Chwaka Bay and Jambiani, in the East Coast of Zanzibar. Eight seagrass species, namely Cymodocea rotundata, Cymodocea serrulata, Thalassia hemprichii, Thalassodendron ciliatum, Syringodium isoetifolium, Halodule uninervis, Halophila ovalis and Enhalus acoroides were recorded in the transects. The mean total biomass of seagrass at Chwaka Bay ranged from 142.4 ± 70.71 to 1652 ± 772.7 g dw/m2 and 212.9 ± 146.2 to 1829 ± 1692 g dw/m2 in station with and without seaweed farms, respectively. At Jambiani, the mean total biomass ranged …

Seed Longevity Of Dominant Plant Species From Degraded Savanna In Semi-Arid Tanzania, Hvm Lyaruu

Tanzania Journal of Science

Artificially buried seeds were followed by periodic exhumation and germination during 21 months in Kondoa Irangi Hills, central Tanzania. Viable seeds from thirteen selected species were buried in polythene envelopes at a depth of 15 cm below woodland vegetation. Lethal germination, fungal decay and insect infestation were singled out as the most important contributors to loss of viability among seeds. Hierarchical clustering based on a seed’s mean viability, seed shape and presence or absence of dispersal appendages, produced three distinct groups: (1) non-dormant seeds (2) seeds with enforced dormancy and (3) seeds with seed coat imposed dormancy. The low decay …

Absolute Migration Of Pacific Basin Mid-Ocean Ridges Since 85 Ma And Their Tectonic Implications For The Pacific Plate, Dcp Masalu

Tanzania Journal of Science

Mid-ocean ridges are major physiographic features that dominate the world seafloor. Their absolute motion and tectonics are recorded in magnetic lineations they created. The absolute migration of mid-ocean ridges in the Pacific basin since 85 Ma and their tectonic implications was investigated in this work and the results indicates that at about anomaly 21 (47 Ma) theEast Pacific Rise (EPR) and Juan de Fuca ridge experienced an abrupt change in their migration direction that persisted until about anomaly 6 (20 Ma), probably due to changes in subductionzone configuration in the northern Pacific. This may represent a period of tectonic instability …

The Proton-Translocating A Subunit Of F0f1-Atp Synthase Is Allocated Asymmetrically To The Peripheral Stalk., Monika G Düser, Yumin Bi, Nawid Zarrabi, Stanley D Dunn, Michael Börsch

Biochemistry Publications

The position of the a subunit of the membrane-integral F0 sector of Escherichia coli ATP synthase was investigated by single molecule fluorescence resonance energy transfer studies utilizing a fusion of enhanced green fluorescent protein to the C terminus of the a subunit and fluorescent labels attached to specific positions of the epsilon or gamma subunits. Three fluorescence resonance energy transfer levels were observed during rotation driven by ATP hydrolysis corresponding to the three resting positions of the rotor subunits, gamma or epsilon, relative to the a subunit of the stator. Comparison of these positions of the rotor sites with those …

Medial Temporal Lobe Bold Activity At Rest Predicts Individual Differences In Memory Ability In Hhealthy Young Adults, Gagan S. Wig, Scott T. Grafton, Kathryn E. Demos, George L. Wolford, Steven E. Petersen, William M. Kelley

Dartmouth Scholarship

Human beings differ in their ability to form and retrieve lasting long-term memories. To explore the source of these individual differences, we used functional magnetic resonance imaging to measure blood-oxygen-level-dependent (BOLD) activity in healthy young adults (n = 50) during periods of resting fixation that were interleaved with periods of simple cognitive tasks. We report that medial temporal lobe BOLD activity during periods of rest predicts individual differences in memory ability. Specifically, individuals who exhibited greater magnitudes of task-induced deactivations in medial temporal lobe BOLD signal (as compared to periods of rest) demonstrated superior memory during offline testing. This relationship …

Pgrmc1: A New Biomarker For The Estrogen Receptor In Breast Cancer, Rolf J. Craven

Pharmacology and Nutritional Sciences Faculty Publications

Estrogen receptor (ER) status is a critical biomarker in breast cancer, in large part because the ER is the target of tamoxifen and similar drugs. In the previous issue of Breast Cancer Research, Neubauer and colleagues used a proteomic approach to identify proteins that are differentially regulated by ER in breast tumors. The authors showed that ER-negative tumors have elevated levels of PGRMC1 (progesterone receptor membrane component-1), a hormone receptor component and binding partner for P450 proteins. In contrast, PGRMC1 was phosphorylated in ER-positive tumors. The staining patterns of ER and PGRMC1 were mutually exclusive in breast tumor sections, and …

Body Weights And Species Distributions Of Birds In Nebraska's Central And Western Platte Valley, William C. Scharf, Josef Kren, Paul A. Johnsgard, Linda R. Brown

Papers in Ornithology

Data are presented on nearly 18,000 bird-captures involving 125 species banded between 1992 and 2005 at two Platte Valley study areas in central and western Nebraska. Weight data for more than 1 1,500 individuals of 74 species are summarized by age, sex and banding site, including several species having larger samples than in any previously published reports. Breeding evidence was obtained for 67 species in one or both locations, and 108 of the total 125 species banded were migrants, 71 percent of which were Neotropical migrants. The largest banding totals were obtained at Cedar Point Biological Station, in Keith County, …

Reduce Costs Of Irrigation Pumping Plants By Improving Efficiency, Thomas Dorn, Sandi Alswager Karstens

Institute of Agriculture and Natural Resources: News Releases

To save energy and money, Nebraska irrigators should check their irrigation pumps for maximum efficiency, a University of Nebraska-Lincoln Extension educator said.

Irrigation pumps that operate at the average efficiency found in university tests are using 30 percent more energy than necessary, said Tom Dorn, extension educator in Lancaster County.

"At today's energy prices, identifying a pumping plant that needs adjustment or repair could save hundreds if not thousands of dollars per year," Dorn said. "Now that irrigation season is over, look at your records and decide which of your pumping plants should be looked at by a professional. If …

Specific Compartmentalization Of Iga Ascs In Mouse Salivary Glands Via Differential Expression Of Chemokines And Chemokine Receptors, Yuet Ching Law

Theses and Dissertations

The mucosal system, which forms a barrier between internal organ systems and the external environment, is frequently exposed to pathogenic microorganisms. Immunoglobulin A (IgA) antibody secreting cells (ASCs) localize in the lamina propria, and produce IgA antibodies which help protect mucosal tissues. The concept of a common mucosal immune system in which IgA ASCs have the ability to populate any mucosal site has been proposed (1, 2). However, recent research has suggested that IgA ASCs primed in different mucosal sites might possess different sets of chemokine receptors, and therefore migrate specifically to particular mucosal locations (3). In this study, the …

Evolution Of Picornaviruses: Impacts Of Recombination And Selection, Nicole Noel Lewis-Rogers

Theses and Dissertations

Picornaviruses are responsible for some of the most common and debilitating diseases affecting humans and animals worldwide. The objectives of this dissertation research were (1) estimate phylogenetic relationships among 11 picornavirus genera and within three species: foot-and-mouth disease virus (FMDV: Aphthovirus) which afflicts cloven-hoofed animals and human rhinovirus A and B (HRV: Enterovirus) which cause the common cold; (2) better understand the impact recombination has on genomic organization and evolution; (3) characterize where positive and purifying selection has occurred in proteins and how selection has influenced phenotype. The dissertation includes four studies. The first chapter provides an overview of the …

Ceramide Kinase And Ceramide-1-Phosphate, Dayanjan Wijesinghe

Theses and Dissertations

Ceramide-1-phosphate (C1P) is a bioactive lipid that has been implicated in many biological processes. Our laboratory has conclusively demonstrated its role in inflammation via activation of cPLA2α. The only known enzyme to date responsible for direct synthesis of C1P is ceramide kinase. Very little was known about this enzyme in terms of its enzyme kinetics and substrate specificity. As CERK is an enzyme that acts on membrane lipids, its kinetics cannot be studied using standard bulk dilutions methods. Thus we developed a surface dilution approach using Triton X 100 mixed micelles for studying the kinetics of CERK. We discovered that …

Hair, Feces And Breath Isotope Fractionation In Alpacas (Llama Pacos), Llamas (Llama Glama) And Guanacos (Llama Guanacoe) From Bolivia And Chile, Lino Constancio Lopez Lopez

Theses and Dissertations

This study was conducted to determinate carbon and nitrogen isotope fractionation in Bolivian and Chilean alpaca, llama and guanaco, hair, breath, plasma and feces. We also wanted to determine forage selection for these camelids using stable isotope technology. From the data, niche feeding and diet selection habits will determinate based on fecal composition. Bolivian sites were located near the high snow Altiplano Mountains at Tomarapi, Sajama, and at the Technical University Oruro's research center at Condoriri, Bolivia. Chilean samples were collected at INIA's (Instituto Nacional de Investigacion Agropecuaria) Kampenaike Research Station, Punta Arenas, Chile. Bolivian alpacas and llamas were 3 …

Nutrient Loading And Eutrophication In The Great Salt Lake, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Exploring The Mialome Of Ticks: An Annotated Catalogue Of Midgut Transcripts From The Hard Tick, Dermacentor Variabilis (Acari: Ixodidae), Jennifer M. Anderson, Daniel E. Sonenshine, Jesus G. Valenzuela

Biological Sciences Faculty Publications

Background: Ticks are obligate blood feeders. The midgut is the first major region of the body where blood and microbes ingested with the blood meal come in contact with the tick's internal tissues. Little is known about protein expression in the digestive tract of ticks. In this study, for analysis of global gene expression during tick attachment and feeding, we generated and sequenced 1,679 random transcripts (ESTs) from cDNA libraries from the midguts of female ticks at varying stages of feeding.

Results: Sequence analysis of the 1,679 ESTs resulted in the identification of 835 distinct transcripts, from these, a total …

Detection Of Recurrent Copy Number Alterations In The Genome: A Probabilistic Approach, Oscar M. Rueda, Ramon Diaz-Uriarte

COBRA Preprint Series

Copy number variation (CNV) in genomic DNA is linked to a variety of human diseases (including cancer, HIV acquisition, autoimmune and neurodegenerative diseases), and array-based CGH (aCGH) is currently the main technology to locate CNVs. Several methods can analyze aCGH data at the single sample level, but disease-critical genes are more likely to be found in regions that are common or recurrent among samples. Unfortunately, defining recurrent CNV regions remains a challenge. Moreover, the heterogeneous nature of many diseases requires that we search for CNVs that affect only some subsets of the samples (without prior knowledge of which regions and …