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Full-Text Articles in Entire DC Network
Pittsburg State University Annual Commencement, Dec 2004, Pittsburg State University
Pittsburg State University Annual Commencement, Dec 2004, Pittsburg State University
Commencement, 1903-Present
Program of undergraduate and graduate commencement exercises at Pittsburg State University on December of 2004
Shellfish Resources And Habitat Characterization Survey For Sebasco Harbor, Phippsburg, Maine, Christopher S. Heinig, Daniel S. Millar
Shellfish Resources And Habitat Characterization Survey For Sebasco Harbor, Phippsburg, Maine, Christopher S. Heinig, Daniel S. Millar
Publications
No abstract provided.
Us-Andean Free Trade Negotiations, Ladb Staff
Graduate Council Report No. 2004-2005-4, University Of Rhode Island Faculty Senate
Graduate Council Report No. 2004-2005-4, University Of Rhode Island Faculty Senate
Faculty Senate Committee Reports and Appendices
No abstract provided.
Winter Commencement: December 17, 2004, University Of North Dakota
Winter Commencement: December 17, 2004, University Of North Dakota
UND Commencement Programs
UND Winter Commencement program from December 17, 2004.
Distribution And Ecology Of Exotic Plants In Wrangell-St. Elias National Park And Preserve, Alaska, Paul Christian Mckee
Distribution And Ecology Of Exotic Plants In Wrangell-St. Elias National Park And Preserve, Alaska, Paul Christian Mckee
Natural Resources
The distribution of exotic plants and site factors influencing their abundance on roads and trails were studied in Wrangell-St. Elias National Park and Preserve during the summer of 2003. Seventeen species of exotic plants were found in the park at 173 locations. The most common species (Taraxacum officinale, Plantago major) were present at all study sites, while some (Trifolium spp., Bromus inermis, Leucanthemum vulgare) were restricted to specific disturbance types and particular areas. Though sampling was limited to areas in which exotic plants were growing, percent cover of exotics was not a significant component of sample sites, and exotic species …
Transient Spatiotemporal Chaos On Complex Networks, Safia Rawoot
Transient Spatiotemporal Chaos On Complex Networks, Safia Rawoot
Physics
Some of today's most important questions regard complex dynamical systems with many interacting components. Network models provide a means to gain insight into such systems. This thesis focuses on a network model based upon the Gray-Scott cubic autocatalytic reaction-diffusion system that manifests transient spatiotemporal chaos. Motivated by recent studies on the small-world topology discovered by Watts and Strogatz, the network's original regular ring topology was modified by the addition of a few irregular connections. The effects of these added connections on the system's transience as well on the dynamics local to the added connections were examined. It was found that …
Synchronization In Biological Systems, Jonathan P. Klaas
Synchronization In Biological Systems, Jonathan P. Klaas
Physics
Synchronization, the adjustment of rhythms via coupling, is an essentially nonlinear effect in coupled dynamical systems. Synchronization is observed in many systems, for example the moon's periods of rotation and revolution, in pendulums suspended from a common support, in swarms of fireflies that flash in unison, and in biological circadian rhythms. Circadian rhythms are periodic fluctuations in multiple physiological systems that have evolved as a consequence of the daily rotation of the earth. These rhythms have been observed in organisms ranging from cyanobacteria to man. In this thesis we will present a conceptually simple model of circadian rhythms to yield …
Soil Properties And Forest Stand Characteristics Along A Toposequence Of The Smith Lake Area Near Fairbanks, Alaska, Lijie Zhu
Plant, Animal and Soil Sciences
Forests, soils and their relationships were studied along a toposequence over an elevation range from 161 meters to 213 meters near Smith Lake on the University of Alaska Fairbanks campus, Fairbanks, Alaska. Forest cover type and understory species composition change along the slope from top to bottom and are related to temperature and moisture. Aspen occurs on the ridge top. Paper birch grows best on the shoulder. White spruce, which has the greatest commercial value, is the only species present on all slope positions; it grows best on shoulder and back slopes. Black spruce dominates on the wet and cold …
Foraging Ecology Of Yellow-Rumped Warblers In An Alaskan Boreal Forest Following A Spruce Beetle Outbreak, Kristen Bartecchi Rozell
Foraging Ecology Of Yellow-Rumped Warblers In An Alaskan Boreal Forest Following A Spruce Beetle Outbreak, Kristen Bartecchi Rozell
Biological Sciences
I examined the foraging ecology of the Yellow-rumped Warbler (Dendroica coronata) several years after an outbreak of spruce beetles (Dendroctonus rufipennis) in the Copper River Basin, Alaska. With increased beetle-induced mortality of white spruce (Picea glauca), a preferred foraging substrate, we predicted warblers would respond through: (1) decreased overall use of white spruce, (2) increased selectivity of live white spruce that remained, and (3) reduced foraging efficiency, reflected by a greater proportion of time spent foraging and lower prey attack rates. We examined warbler foraging behavior and arthropod biomass on commonly used foraging substrates, and in stands with low-moderate ( …
King Eider Wing Molt: Inferences From Stable Isotope Analyses, Michael J. Knoche
King Eider Wing Molt: Inferences From Stable Isotope Analyses, Michael J. Knoche
Biological Sciences
The western North American population of the king eider is thought to have declined by over 50% between 1974 and 1996 without an apparent cause. The non-breeding period of king eiders consists of 80-100% of their annual cycle if not impossible by observation. I used stable carbon and nitrogen isotope values of feathers and muscle to examine the wing molt and migration ecology of king eiders in 2003. Eider primary feathers were isotopically homogenous along the length of the feather, implying invariable diets during wing molt. Captive eiders in their hatch-year did not fractionate nitrogen isotopes, potentially indicating preferential protein …
Genetic And Chemical Studies Relating To Α-Aminoisobutyri Acid (Aib) Metabolism, Jeffrey A. Bickmeier
Genetic And Chemical Studies Relating To Α-Aminoisobutyri Acid (Aib) Metabolism, Jeffrey A. Bickmeier
Chemistry and Biochemistry
The non-protein amino acid a-aminoisobutyric acid (Aib) occurs naturally in soil. Burkholderia cepacia utilizes Aib as a sole nitrogen source by virtue of a 2,2-dialkylglycine decarboxylase, which is encoded by the dgdA gene. In this study, 30 prokaryotes were cultured on minimal media containing Aib as the sole nitrogen source and identified by 16S rRNA gene sequencing. Several attempts were made to clone dgd genes from these organisms. Plasmid libraries were constructed in E. coli from DNA isolated from four Aib-utilizing bacteria. Libraries were screened for clones which demonstrated the ability to grow on Aib containing media and therefore contained …
Tribological Comparison Of Materials, Bing Shi
Tribological Comparison Of Materials, Bing Shi
Chemistry and Biochemistry
Approximately 600,000 total joint replacement surgeries are performed each year in the United States. Current artificial joint implants are mainly metal-on-plastic. The synthetic biomaterials undergo degradation through fatigue and corrosive wear from load-bearing and the aqueous ionic environment of the human body. Deposits o f inorganic salts can scratch weight-bearing surfaces, making artificial joints stiff and awkward. The excessive wear debris from polyethylene leads to osteolysis and potential loosening of the prosthesis. The lifetime for well-designed artificial joints is at most 10 to 15 years. A patient can usually have two total joint replacements during her/his lifetime. Durability is limited …
Genetics And Sex Expression In Alaskan Populations Of Silene Acaulis, Amber Klaas
Genetics And Sex Expression In Alaskan Populations Of Silene Acaulis, Amber Klaas
Biological Sciences
Gynodioecy, the coexistence of hermaphrodites and females within plant populations, is often caused by an interaction between maternally-inherited cytoplasmic male sterility (CMS) genes and nuclear male fertility restorer genes. Previous population studies have found cytoplasmic alleles associated with femaleness. We analyzed the spatial distributions of mitochondrial and chloroplast alleles and the sexual phenotype of individuals within five Alaskan populations of Silene acaulis. Sex ratios were variable between two mountain ranges in this study, possibly due to differences in the frequencies of CMS genes. Clustering of mitochondrial alleles, but not sex, was found within two populations at a scale <̲ 2 m. This result may be because maternally-inherited mitochondrial genes are locally spread through seed, but nuclear restorers are spread through pollen and seed. We also investigated sex ratios and CMS genes temporally and did not find patterns of changing sex ratios or mitotypes across size classes. This does not support the theory that females and the mitotypes they carry have been selected against over time, implying that female clusters were not broken-up due to pollen limitation. Patterns of mitochondrial and chloroplast alleles suggest either non-maternal inheritance of cytoplasmic markers or multiple reversals in the evolutionary history of cytoplasmic markers.
The Effect Of Varying Active Layer And Soil Climate On Net Nitrogen Mineralization And Foliar Nitrogen In A Boreal Watershed, Jennifer K. Rohrs-Richey
The Effect Of Varying Active Layer And Soil Climate On Net Nitrogen Mineralization And Foliar Nitrogen In A Boreal Watershed, Jennifer K. Rohrs-Richey
Biological Sciences
In the Alaskan boreal forest, black spruce (Picea mariana) is the forest type most severely limited by nitrogen mineralization. Nitrogen cycling in upland black spruce forests of the Interior is affected by the interactions between permafrost, soil climate, and litter quality. Permafrost and soil climate also play a significant role in nitrogen acquisition of shrubs, which are important for biomass turnover and element cycling in the understory. This study took place in a boreal watershed and addressed the question of how variation in soil climate and active layer between north and south-facing aspects affected 1) net nitrogen mineralization rate and …
Market Opportunities For Carbon Sequestration In Alaska, Jennifer Elizabeth Duval
Market Opportunities For Carbon Sequestration In Alaska, Jennifer Elizabeth Duval
Economics
Global climate change has been at the forefront of environmental concerns for the last few decades. Based on the success of the United States' sulfur dioxide cap-and-trade program, a market for greenhouse gas emissions has slowly emerged. Russia's recent ratification of the Kyoto Protocol will bring an international market into force in February 2005. This thesis examines the economic theory behind cap-and-trade markets as solutions for environmental problems and discusses the characteristics of the markets for greenhouse gas emissions. The opportunities for Alaska's participation are examined, particularly offsetting diesel emissions from rural generators with wood or alternative energies. The calculations …
2004 Fall Commencement Program: Winona State University, Winona State University
2004 Fall Commencement Program: Winona State University, Winona State University
WSU Commencement Programs
This is the Winona State University Fall 2004 commencement program. Commencement was on Friday, December 17, 2004.
Assessing The Production Of Sockeye Salmon (Oncorhynchus Nerka) At Chilkat Lake, Southeast Alaska, Using Current Trophic Conditions And The Paleolimnologic Sediment Record, David Barto
Fisheries
Anadromous sockeye salmon are the only Pacific salmon that require an extensive rearing period in a lake environment. Recent studies suggest changes in lake nutrient inputs are directly related to the magnitude of annual spawning populations (escapement), and can be quantified by sediment stable isotope analysis of nitrogen ¹⁵N). Marine nitrogen supplied by returned salmon is enriched in ¹⁵N relative to the freshwater nitrogen, which is derived from atmospheric N₂ (ð¹⁵N=0 ⁰/₀₀). Recent (1987-1996) limnological investigations of Chilkat Lake, Alaska, matched to brood year escapement estimates, indicate that sockeye marine-derived phosphorus and nitrogen contributed up to 87% and 20%, respectively, …
Phylogenetic Relationships And Identification Of Juveniles Of The Genus Sebastes, Zhuozhuo Li
Phylogenetic Relationships And Identification Of Juveniles Of The Genus Sebastes, Zhuozhuo Li
Fisheries
The genus Sebastes is speciose and most members are distributed in the northeastern Pacific Ocean (NEP). Historically, morphology has been the basis for species identification and determination of phylogenetic relationships. However, because many Sebastes species overlap in range and are similar in morphology, especially during early life stages, morphological characters are often inadequate for species identification. This study examines the potential of using restriction site variation in the mitochondrial NADH-dehydrogenase subunits -3 and -4 and 12S and 16S ribosomal RNA genes to resolve the problems in species identification and phylogenetic relationships, particularly assignments to subgenera. Of the 71 species representing …
Maturation Of Walleye Pollock, Theragra Chalcogramma, In The Eastern Bering Sea In Relation To Temporal And Spatial Factors, Jennifer Paige Stahl
Maturation Of Walleye Pollock, Theragra Chalcogramma, In The Eastern Bering Sea In Relation To Temporal And Spatial Factors, Jennifer Paige Stahl
Fisheries
Walleye pollock, Theragra chalcogramma, are both ecologically and commercially important in the eastern Bering Sea (EBS). Maturity is a critical parameter in the stock assessment to set annual total allowable catch. Pollock maturity has not been examined in the EBS since 1976, and possible interannual and geographic variation has not been studied to date. Our goal is to estimate correct maturity schedules for EBS pollock. Maturity data, fish lengths and macroscopic maturity stages were collected aboard pollock trawlers during winter 2002 and 2003 across the EBS from 10,197 pollock. Similar data were collected by NMFS scientists during hydroacoustic surveys from …
How Chemical Differences In Dissolved Organic Matter Relate To Vegetation, Sarah Jean Seelen
How Chemical Differences In Dissolved Organic Matter Relate To Vegetation, Sarah Jean Seelen
Engineering
The purpose of this study was to better understand the link between dissolved organic matter (DOM) in soil leachate and different vegetation attributes. Soil cores were collected from the Caribou Poker Creeks Research Watershed (CPCRW) and subjected to a laboratory leaching procedure. The leachates were then subjected to a number of analytical tests, including pyrolysis-gas chromatography/mass spectrometry (py-GC/MS). Py-GC/MS is a 'molecular fingerprinting' technique that was used to help determine similarities and differences in organic matter leached from soils with different vegetation attributes. Numerous statistical tests were performed including Student-t, analysis of variance, principal components analysis, and partial least squares …
Shrub Expansion In Arctic Alaska: 50 Years Of Change Documented Using Aerial Photography, Ken Tape
Shrub Expansion In Arctic Alaska: 50 Years Of Change Documented Using Aerial Photography, Ken Tape
Geosciences
Evidence from arctic Alaska suggests that the terrestrial landscape is changing in response to warming. Between 1946 and 1951, several thousand low-altitude panchromatic oblique aerial photographs were taken as part of geologic reconnaissance and exploration of Alaska's Arctic Slope and Brooks Range. For this study, 202 of the landscapes in the old photographs were re-photographed. Comparison of the old and new photographs revealed an increase in shrub cover in the last half-century. The changes were observed over a 220,000 km2 tract of arctic tundra, and it is likely that they are more widespread. A quantitative method for comparing the photographs …
Natural Resource News, Vol. 04, No. 3 (December 2004), N/A N/A
Natural Resource News, Vol. 04, No. 3 (December 2004), N/A N/A
Natural Resource News
No abstract provided.
University Of Nebraska At Omaha, December Commencement 2004, University Of Nebraska At Omaha
University Of Nebraska At Omaha, December Commencement 2004, University Of Nebraska At Omaha
Commencement Programs
No abstract provided.
Non-Linear Dynamics Of Marine Ecosystem Models, Georgina Anne Gibson
Non-Linear Dynamics Of Marine Ecosystem Models, Georgina Anne Gibson
Marine Biology
Despite a rapid trend towards more realistic Nutrient-Phytoplankton-Zooplankton (NPZ) models, in which zooplankton are presented with multiple nutritional resources, investigations into the fundamental dynamics of these newer models have been limited. The objective of this dissertation was to explore the dynamical behavior of such NPZ models parameterized for the coastal Gulf of Alaska. With alternative stationary forcing regimes and zooplankton grazing functions, the dynamics of one-dimensional NPZ models were investigated for a range of specific predation rates (h) and predation exponents (q), which together define the form of the predation (model closure) function. Oscillations in state variables are shown to …
Characterizing Glucocorticoid Levels In Five Species Of Sea Ducks Occurring In Alaska, Peter B. Nilsson
Characterizing Glucocorticoid Levels In Five Species Of Sea Ducks Occurring In Alaska, Peter B. Nilsson
Marine Biology
Stress hormone analysis, used in conjunction with other physiological parameters, may help identify factors affecting sea duck populations in their natural environment. Corticosterone, the primary 'stress hormone' in birds, is secreted in response to a stressor and enhances an individual's chance of survival by inducing physiological and behavioral changes. Establishing a valid method for evaluating stress hormone levels in sea ducks and gaining basic information on baseline concentrations and stress response in these birds are important first steps to identify factors that may negatively affect sea duck populations. This study validated a radioimmunoassay (RIA) procedure to measure corticosterone concentrations in …
Development And Characterization Of Controlled Drug Delivery Using Nanoparticles, Li Chen
Development And Characterization Of Controlled Drug Delivery Using Nanoparticles, Li Chen
LSU New Orleans Theses and Dissertations
The objective of this project was to develop new controlled drug delivery systems using nanomeric particles and characterize the delivery of drugs into cells in real time by digital fluorescence imaging microscopy techniques. The project is based on the idea that it could be possible to improve efficacy of drug molecules when encapsulated in nanometer-sized particles. Due to their small dimensions the particles could permeate through cells and tissues and even through the blood brain barrier. The anti-cancer drug Doxorubicin was encapsulated into biodegradable Poly (DL-lactideco- glycolide) (PLGA) nanoparticles by simple nanoprecipitation method. The small size of these particles (<200nm) could be beneficial to realize passive tumor-targeted drug delivery through enhanced permeability and retention (EPR) effects. These drug-containing particles showed a sustained release profile. Fluorescence images indicated that these particles can be internalized by human breast cancer MCF-7 cells by non-specific endocytosis. The bioactivity of the drugs was also tested against cell culture. The results indicated that DXR-loaded PLGA nanoaprticles could be used to deliver Doxorubicin into breast cancer cells.
Effects Of Chronic Sleep And Food Deprivation On In Vivo Levels Of Prepro-Hypocretin (Pph), Kelly Dunn
Effects Of Chronic Sleep And Food Deprivation On In Vivo Levels Of Prepro-Hypocretin (Pph), Kelly Dunn
LSU New Orleans Theses and Dissertations
The hypocretin peptides are two hypothalamic peptides known to be involved in both sleeping and feeding behavior, however their specific roles in these domains are not well understood. The present study sought to determine the effect of chronic (72-hour) sleep deprivation and (48-hour) food deprivation on preprohypocretin (PPH), which is the precursor for the hypocretin peptides. PPH levels were visualized and quantified via in situ hybridization. A three-factor ANOVA ( group x dorsal/ventral x medial/lateral) revealed a significant effect of subregion, specifically dorsal/middle and ventral/medial exhibited elevated PPH levels, however there was no effect of group. A between group one-way …
Kinetics Of Dcod Consumption By Bacterial Suspensions, Shirley Poliszuk
Kinetics Of Dcod Consumption By Bacterial Suspensions, Shirley Poliszuk
LSU New Orleans Theses and Dissertations
The aim of this investigation was to study the kinetics of readily biodegradable soluble substrate, and the interactions between the bioflocculation process and such kinetics. Several batch test experiments were performed at different soluble-substratebiomass ratios in order to evaluate its impact on the kinetics and the order of the reaction. Similarly the consumption of dissolved substrate was compared using two different bacterial suspensions: (1) flocculated suspension; and (2) dispersed cells suspensions. In this research flocculated biomass from a complete mixed activated sludge (CMAS) system was tested using sequencing batch reactors (SBR). Results indicate that when the So/Xo ratio is low …
Relationship Between The Sludge Settling Characteristics And The Parameters Of The Activated Sludge System, Jose Angel Rojas
Relationship Between The Sludge Settling Characteristics And The Parameters Of The Activated Sludge System, Jose Angel Rojas
LSU New Orleans Theses and Dissertations
The activated sludge process is one of the most commonly employed domestic and industrial waste treatment process. Different types of mathematical models have been proposed for design and operation of this process, most of which do not consider the relationship between the sludge settling characteristics and the aeration unit performance. This project studies the validity of a model developed by La Motta (2004b) which links the operating parameters of an activated sludge system and the classical limiting flux sludge settling theory. Favorable results were obtained demonstrating that the model predicts very similar values of the parameters of the system in …