• Beetles and spiders as indicators of forest recovery on Prince of Wales Island, Alaska

      Stockbridge, Jill M.; Sikes, Derek S.; Wagner, Diane; Kruse, James J. (2014-08)
      Commercial logging is among the most important disturbance factors affecting forest biota. An indirect effect of commercial logging is minimal understory within young even-aged forests, which can decrease forest biodiversity. To improve management of young even-aged forest stands within the Tongass National Forest (TNF), foresters are testing alternative forestry practices under the Tongass-Wide Young-Growth Studies (TWYGS). However, little is known about how the new thinning treatments included in the TWYGS will affect forest biota and the recovery of young even-aged forest stands as they transition back into old growth forests. To investigate the effects of thinned secondary growth on forest biota in the TNF on Prince of Wales Island, Alaska, I compared spider and beetle biodiversity in thinned secondary growth to old growth forest stands, clearcuts, and un-thinned secondary growth. Pitfall traps, Berlese funnels, and Lindgren© funnel traps were used to collect spiders and beetles in each forest type to compare species richness, diversity, and assemblages, as well as to identify possible ecological indicators within each habitat. I hypothesized that thinned secondary growth would have a mix of old growth and clearcut species and be further in the process of recovery than un-thinned secondary growth. I found that (1) spider and beetle species richness and diversity from thinned secondary growth were not significantly different from other forest treatments; (2) spider assemblages in thinned secondary growth were significantly different from other forest treatments, whereas beetle assemblages were not different; (3) spider and beetle assemblage structure was mainly influenced by Leaf Area Index (LAI) and; (4) spider and beetle ecological indicators of clearcuts and old growth stands were found within thinned and un-thinned secondary growth stands. These findings support my hypothesis that thinned secondary growth would have both old growth and clearcut species; however, thinned secondary growth was not found to be further in the process of recovery than unthinned secondary growth at the time of this study. Although thinned secondary growth was not further in the process of recovery, it did not adversely affect the biodiversity of spiders and beetles. My results suggest that logging on Prince of Wales Island can change spider and beetle assemblages, but it doesn't negatively impact species richness or diversity. Thinned secondary growth spider and beetle biodiversity may be in the process of recovery to the biodiversity seen in old growth forests. Therefore, spider and beetle biodiversity may resemble old growth forest biodiversity as LAI values increase with closing canopy in thinned secondary growth forest stands. In addition, a checklist of arthropods collected on Prince of Wales Island, Alaska, as part of this work, combined with records from other projects and publications, are included followed by a description of a new species I discovered, Caurinus tlagu Sikes & Stockbridge 2013 (Mecoptera, Boreidae, Caurininae).
    • Behavior Of Granular Materials Under Cyclic And Repeated Loading

      Minassian, George H.; Raad, Lutfi (2003)
      Granular layers are essential contributors to the structural integrity of the pavement system, their premature deformation radically decrease support of the asphalt concrete surface layer, thus leading to the early deterioration of the overall pavement structure. This research was conducted to better understand the behavior of granular materials when subjected to the complex nature of traffic loading. Long-term triaxial tests were conducted on typical Alaskan base course material using both repeated as well as cyclic loading to also account for the shear reversal effects induced by wheel load. Results show that the shear reversal component of the traffic loads, which have been ignored so far, induces considerable damage to the granular layers. Models were presented to predict the different soil moduli while also accounting the effect of strain hardening or densification due to the repetitive nature of the loads applied. Moreover, a simple yet powerful model was presented to predict accumulated permanent strains as function of the stress state, number of load repetitions and the strength level applied. The results obtained in this study also show a clear indication of the existence of given stress level limit beyond which incremental collapse of the system takes place. Furthermore, regions of instability of granular layers subjected to dynamic loading have been defined using a simple response parameter and monotonic shear strength of the soil. An effort was made to explain the instability zones identified in this research by the shakedown theory.* *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Microsoft Office.
    • The behavior of tellurium during copper ore processing at the American Smelting and Refining Company (Tucson, AZ)

      Josephson, Amy E.; Hayes, Sarah M.; Newberry, Rainer J.; Trainor, Thomas P. (2016-08)
      Essentially all tellurium (Te), an element used in solar panels and other high technology devices, is recovered as a byproduct of copper mining. Recent increases in demand have sparked questions of long-term supplies of Te (crustal abundance ~3 μg∙kg-1). As part of a larger study investigating Te resources, this project examines the behavior of Te during Cu ore mining, smelting, and refining at the American Smelting and Refining Company (Tucson, AZ) as a first step toward optimizing Te recovery. Mass balance calculations estimate that only 4 ± 1% of the Te in the ore reports to the Cu anodes, while 60 ± 30%, 0.8 ± 0.2% and 5.8 ± 0.4% is lost in the tailings, slag, and dust, respectively. The uncertainties reported are the standard deviation of analytical measurements, but due to heterogeneity of Te distribution in the ore, the actual uncertainty is likely higher. Microprobe data shows that Te in the concentrate is mainly present as telluride minerals, but substitution into sulfides most likely also occurs. X-ray fluorescence (XRF) mapping showed that Te is collocated with S in the raw anode slimes, pressed anode slimes, and doré furnace soda slag. X-ray absorption spectroscopy (XAS) was used to examine Te speciation in anode slimes. It was found that Te oxidizes during the Cu ore smelting process, with 44% Te4+ in the flash furnace SO₂ filter. Te also showed 32% Te4+ in the raw and pressed anode slimes. The doré furnace soda slag and dust filter showed the most oxidation of Te at 57% Te4+ and 60% Te6+ respectively. These results indicate several points in the extraction process that could be examined further to determine if additional Te might be recovered from the overall process.
    • Behavior, physiology, biological age, and cultural role of long-lived Bering Sea seabirds

      Young, Rebecca C.; Kitaysky, Alexander S.; Chapin, F. Stuart; Carothers, Courtney L.; Haussmann, Mark F. (2014-05)
      This dissertation focuses on the intersection of behavior, physiology, and biological age. Biological age is a measure of an organism's progress through life, and it incorporates chronological age as well as the actions of environment and innate quality at the individual level. We estimate biological age using telomere length as a biomarker. Telomere degradation in relation to oxidative stress links it directly to purported proximate mechanisms of aging under the free radical theory of aging. Short telomeres, or telomere loss, have been related to ecological indicators of lowered fitness. Our work focuses on aging in the thick-billed murre (Uria lomvia), a long-lived seabird breeding in the Bering Sea. Seabirds exemplify the "slow-lived" paradigm; they have long lifespans, low reproductive rates, and high adult survival. First we address the relationship between chronological age and telomere length in the thick-billed murre. We found longer telomeres in chicks than in adults, and longer telomeres in adult females than in adult males. Then we examine biological age, telomere length, in relation to physiology and behavior of murres equipped with a recording device to monitor foraging behavior. Chapter two describes the physiological and reproductive investment of these murres in relation to their biological age, while chapter three addresses the habitat and prey choices made by these birds in relation to sex, biological age, and environment. Behaviorally murres remain healthy into their old ages, with physiological diving capacity similar or improved in old birds. Stress patterns demonstrate that when conditions are good, older birds are more stressed, but experience buffers their stress levels under poor conditions. The fourth chapter of this thesis deals with seabirds as part of the larger socio-ecological system that includes the indigenous people living on the Pribilof Islands. The Priblovians value seabirds, but are members of periphery communities troubled by a poor economy and disconnected from a past that was tightly coupled to the natural world. Development requires active management by local stakeholders to reconnect with cultural and economic resources (like seabirds) and to make the communities more sustainable and resilient.
    • Beneath the terrible surface

      Lagergren, Jenny Kristine (2002-05)
      'Beneath the terrible surface' is concerned with connections among people, animals, objects, and land that are important, but subtle and often overlooked. The poems are concrete and find meaning through a moment slowed downed and viewed from a new angle, which ultimately conveys emotion. While moments are described, the goal is not description, but exploration. A point in time becomes important by what happens or does not happen and by what is noticed and felt by the speakers and characters. Though not always positive, they detail an awareness of the intricate, important and sometimes invisible connections between many forms of life. The collection contemplates what it takes to love a landscape, appreciate animals, and notice, react, and care for life that does not lend itself to immediate liking.
    • Beneficiation of rare earth minerals from Bokan Mountain: Dotson Ridge ore

      Narantsetseg, Purevbaatar; Наранцэцэг, Пүрэвбаатар; Ganguli, Rajive; Ghosh, Tathagata; Akdogan, Guven (2014-12)
      The purpose of this research work was to study the beneficiation of rare earth ore of the Bokan Mountain -- Dotson Ridge deposit, located near Ketchikan, Alaska. Rare earth element (REE) composite ore samples from the Bokan Mountain -- Dotson Ridge deposit were tested using gravity concentration, magnetic separation, flotation, and leaching techniques to separate the REE. The composite ore sample was a product of a preliminary x-ray sorting process. Qualitative electron microprobe analysis of the ore showed that most of the REE minerals in the ore were silicate minerals. Since the electron microprobe analysis samples were coated with carbon during sample preparation, the carbon element was inactivated for analysis. Because of this, carbonate compounds of minerals' particles could not be detected. 95% of the REE mineral particles appear to be smaller than about 10 μm in size (about 100 μm² in area). For the gravity concentration, light rare earth elements (LREE) and heavy rare earth elements' (HREE) individual elemental recovery values were in the ranges of 49.6-52.8% and 46.3-48.8%, respectively, at 25% of mass yield. In order to separate a larger amount of the REE, a wet high intensity magnetic separation (WHIMS) test was carried out on tailings of the gravity concentration tests. The HREE individual elemental recovery values ranged from 56.3-63.1% at 37% mass yield, while LREE individual elemental recovery values were in the 57.9% - 59.1% range. For the combined gravity and magnetic separation processes, the net individual elemental recovery values of the LREE and the HREE were in the range of 79.6-80.5% and 76.5-80.9%, respectively. The combined mass yield of the gravity and magnetic separation processes was 3%. Direct leaching tests conducted on the composite ground ore feed yielded high individual elemental recovery values of 90-92% of the LREE. The HREE individual elemental recovery values ranged from 56.5-87.3%. In the leaching, 20% HCl was used in the 1st and 2nd stages with a duration of 2 hrs in each stage at 90°C. The solid percentage of the leach slurry was 20% w/w. The composite ground ore sample was tested in conventional flotation using a 2.0 L capacity Denver cell. In the flotation, 0.05 kg/tonne of Cytec Aero 6493 collector, 0.05 kg/tonne of Cytec Aero Froth 88, and 0.1 kg/tonne of sodium metasilicate as a depressant were used. Pulp pH was set around 9. Results showed individual elemental recovery values in the range of 44.6-50.4% or the LREE. The HREE individual elemental recovery values ranged from 27.9-44.5%. The mass yield of the flotation was 23%. The flotation recoveries reported here are significantly lower than what was achieved previously. For the Leach after flotation process, leaching was conducted on the first concentrate of flotation. Individual elemental recovery values of the LREE and HREE were 94.7-96.5% and 61.1-90.5%, respectively. The concentrate was leached using 20% HCl in both the 1st and 2nd stages, with a duration of 2 hrs in each stage at 90°C. Flotation/Leach process net recoveries of LREE by individual elemental values ranged from 42.2-48.5%. HREE net recoveries by individual elemental values ranged from 17.1-41.4%.
    • Benthic community development in Boca de Quadra, Alaska

      Winiecki, Carol Irene (1986-05)
      The purpose of this experiment was to find ways of evaluating the community development in Boca de Quadra, a fjord in southeast Alaska, after a severe physical disturbance. Containers of defaunated sediment were used near the head of the fjord to simulate the benthic habitat after such a disturbance. Important features of community development were described, potential indicator taxa were selected, and the extent of community development was examined. Seasonal variations tended to mask the developmental trends. However, samples collected during the same season, but representing various lengths of colonization, allowed developmental trends to be observed in faunal composition, numbers of taxa, density, biomass, and diversity. Maldanidae, Nematoda, Lumbrineris luti. Leitoscoloplos pugettensis, Pholoe minuta. and Spionidae are potential indicators of community maturity.
    • Benthic invertebrate macrofauna of the Eastern Continental shelf of the Bering and Chukchi Seas

      Stoker, Sam W. (1978-12)
      The overall view presented by this study is of closely interrelated Bering/Chukchi benthic community system that extends unbroken over the entire continental shelf, with the Chukchi Sea benthos probably relying heavily on the Bering Sea for both food supply and possibly recruitment. Indications are that this is a highly productive and relatively stable benthic system comprised of at least eight major faunal zones of considerable complexity. The environmental factor correlating most strongly with the distribution of these faunal zones and with distribution of individual major species appears to be sediment type, though summer bottom temperature may also be critical. The distribution of standing stock biomass in relation to diversity suggests predation pressure on the southern and northern extremes of the study area, presumably the result of benthic-feeding marine mammal populations and possibly, in the case of the southern region, demersal fish. In general terms it appears to be a strongly detrital-based trophic system, with an elevated standing stock biomass observed in the Bering Strait and southern Chukchi Sea region, probably the combined result of high near-surface primary productivity distributions and current structure. The benthic fauna over this region appears to be dominated by boreal Pacific forms, probably also a result of the current structure, with high Arctic forms frequent only in the northern waters.
    • Benzene and toluene mixing ratios in indoor air of homes with attached garages and measurement of respective biomarkers of exposure and ventilation effects

      Isbell, Maggie Ann; Duffy, Larry (2000)
      Benzene and toluene mixing ratios were measured in the indoor air of homes with attached garages for several seasons using a thermal desorption GC-FID sampling and analysis protocol (EPA T0-17). Benzene in the living area of these homes ranged from 1--72 ppbv and toluene ranged 3--111 ppbv. The garage levels of benzene ranged from 8--304 pbbv and the toluene levels ranged from 14--591 ppbv. Numerous experiments and a model support the hypothesis of a single source of toluene and benzene. Source strength estimate calculations supported the hypothesis that gasoline in the attached garage is the primary source of these compounds in living area air. They also showed that the home with the air-to-air heat exchangers and forced ventilation had less transport of aromatics than an unventilated home. Perturbation experiments showed that a metal gas can filled with gasoline in the garage and an indoor window open were important factors for benzene and toluene levels in the living areas of the homes. For most experiments, weighted regression analyses of toluene and benzene mixing ratios were consistent with a sole source. Finally, no correlation was observed between the levels of benzene and toluene measured in living areas and their respective urinary biomarkers: t,t-MA and hippuric acid.
    • Benzene as an indoor air pollutant in Fairbanks, Alaska

      Ricker, Janet Elaine (2000-08)
      Benzene is a known carcinogen found in gasoline, automobile exhaust, cigarette smoke, and organic solvents. Previous studies suggest that sources of chemicals within the home are the major factors influencing personal exposure to benzene. Indoor air was sampled for benzene in order to determine the concentrations present in Fairbanks homes, and to indentify what factors might be associated with higher concentrations. Sampling sites were limited to homes with attached garages and with no smokers in the household. A wide range of benzene concentrations was observed in the eight homes sampled. The highest concentration was about 70 ppbv, and the concentration in most homes was at or above 4 ppbv. The primary source of benzene appears to be gasoline, most likely from small engines (such as lawnmowers) stored in the attached garage. More sites, including homes with attached garages that contain various numbers of small engines, need to be sampled to confirm these conclusions.
    • Best practices and metrics for virtual reality user interfaces

      Byam, Jay; Chappell, Glenn; Lawlor, Orion; Metzgar, Jonathan (2019-12)
      Virtual Reality (VR) technology has become increasingly effective and accessible within the past decade [15]. With this increase in the technology’s prevalence and cultural significance, certain interaction techniques and design choices have emerged as the most widely used and recommended. This research effort employs a VR experiment in which multiple selection methods, interface placements, and navigation techniques are compared side-by-side, and performance metrics and preference data are collected. Both best practice and to-be-avoided methods are examined, and the performance and preference data is analyzed. Determinations made based on the data gathered are partly in-line with expectations according to best practices, partly inconclusive, and partly contrary to the expected performance and preference results. Results suggest that virtual laser pointers and tapping are equally recommendable selection methods for most VR experiences, hand-mounted menus produce the best results overall, and despite performance advantages, joystick navigation should be avoided in VR due to user comfort concerns.
    • Better understanding of production decline in shale gas wells

      Harongjit, Kananek; Ahmadi, Mohabbat; Patil, Shirish; Dandekar, Abhijit (2014-08)
      Production data from the Eagle Ford shale (an analog to the Alaska Shublik shale) was collected from two neighboring counties and analyzed to correlate well performance with completion parameters including length of horizontal wellbore and number of hydraulic fracturing stages. Thirty-eight dry gas wells with production history range of 18-43 months were analyzed using 6 different decline curve analysis (DCA) models including Arps' exponential, harmonic and hyperbolic, power law exponential (PLE), logistic growth analysis (LGA) and Duong's models. In the matching process, 2/3 of history was used to tune the DCA models and their forecasts were compared to the remaining 1/3 of real history. The matching results were analyzed based on production history length and flow regime to have better understanding of limitations and capabilities of each DCA model. Reservoir simulation models, constructed using range of realistic data and actual completion practices of 4 select wells, were employed to assess reasonable values of remaining reserve and remaining well life that were used as benchmarks for comparison with DCA results. The results showed that there was no strong correlation between well performance (average first year production rate) and the horizontal leg or the number of fracturing stages. This was an indication of extremely heterogeneous medium. In most cases, the accuracy of the DCA models increased when longer production history was used to tune the model parameters. LGA seems to be the most accurate DCA model since it gave the highest matching accuracy 71% of the total wells when using longest history length of 31 months. As the flow regime is concerned, LGA model also performed very well matched in 57% of the wells exhibiting only transient flow and 63% for the wells showing transient flow during early production time followed by boundary-dominated flow during late production. Moreover, the remaining reserve and well life of the select wells predicted by LGA fell into reasonably close range of the estimates from the reservoir simulations.
    • Between us

      Mulcrone, Katherine Jean (2005-05)
      Between Us is the first-person account of Louise Halsey's return to her childhood home after her brothers' tragic motorcycle accident. Her brother Danny lies unconscious, but the strength of their bond grants Louie unexpected encounters with him inside the family home. Her conversations with Danny force Louie to reconsider the issues that have driven her family apart and her role in them. The novel begins with a series of vivid dreams which disconcert Louie and lay the groundwork for her to begin piecing together the unraveling of her family. Current sentiments as expressed and relationships as presented in Louie's conversations with family members are echoed by her memories of past events. Danny's death leads Louie to acknowledge that although rebuilding her family requires difficult work, it is work worth doing.
    • Bilingual research centers in an Alaska studies classroom

      Sipary, Julia; Siekmann, Sabine; John, Theresa; Martelle, Wendy (2015-12)
    • Bioanalytical Development Of Charged Cyclodextrin Capillary Electrokinetic Chromatography And Microperfusion Sampling To Study Endogenous D-Serine And L-Glutamate Efflux In Brain

      Kirschner, Daniel L.; Greene, Thomas (2009)
      A multitude of studies have revealed specific biological mechanisms that contribute to D-amino acid action and regulation in the mammalian central nervous system. The remarkable increase in our understanding of D-amino acid function and distribution in mammals is in many ways a result of the development of sensitive enantioselective separation strategies that allow for quantification in real biological samples. In capillary electrokinetic chromatography (cEKC) the most powerful chiral resolving agents are anionic cyclodextrins (CDs), yet these have not previously been investigated for chiral bioanalysis of amino acids. The focus of this dissertation research was to investigate for the first time the feasibility of and application of anionic cyclodextrins as resolving agents in bioanalytical chiral separations of amino acids. This dissertation encompasses (1) the development of a new bioanalytical separation utilizing capillary electrophoresis laser induced fluorescence (CE-LIF) with sulfated-beta-cyclodextrin for analysis of D-serine (D-ser) and L-glutamate (L-glu) in mammalian brain, (2) the first synthesis and characterization of 6 members of a new family of single isomer sulfoalkyl cyclodextrins, (3) initial studies on chiral analysis of amino acids using single isomer sulfoalkyl CDs, and (4) development and application of a novel microperfusion sampling approach for acute brain slices and coupling of this method to the developed chiral CE-LIF for studying magnitude and timing of D-ser and L-glu efflux from acute hippocampus in response to modeled cerebral ischemia. The results of these studies demonstrate that (1) anionic CDs are powerful chiral selectors for amino acids and can be applied for sensitive bioanalysis of D-amino acids including D-ser, D-glu, and D-asp in brain samples; (2) single isomer sulfoalkyl CDs can be synthesized by regioselective reaction chemistry; (3) single isomer sulfoalkyl CDs are excellent resolving agents for amino acid analysis and may be valuable for bioanalytical chiral applications; and (4) microperfusion sampling coupled to CE-LIF can be used to analyze dynamic changes in the magnitude and timing of neurochemical efflux from single acute hippocampus slices exposed to modeled ischemia. Results of these latter studies suggest that D-ser and L-glu efflux occurs simultaneously in acute hippocampus with similar timing but differing magnitudes.
    • Bioassay and distribution of thiamine in the sea

      Natarajan, Kottayam Viswanathan (1965-05)
    • Biochemical and microbiological assessments of dried Alaska pink salmon, red salmon and Pacific cod heads

      Biceroglu, Huseyin; Smiley, Scott; Crapo, Charles; Bechtel, Peter J. (2012-05)
      Fish heads are generally considered as unsuitable byproducts for human consumption in the United States. The initial objective was to compare the moisture content and water activity levels on dried pink salmon (Oncorhynchus gorbuscha) and dried red salmon (O. nerka) using different temperature and time integration. The secondary objective was to compare shelf life characteristics, rancidity and mold growth, between dried pink dried salmon and dried Pacific cod (Gadus macrocephalus) heads stored for up to 180 days at the ambient temperature (21°C) for East African seafood markets. The third objective was to assess the antioxidant effects for frozen and dried pink salmon heads stored for up to 60 days. In a preliminary experiment, dried red salmon heads were found unsuitable due to the water activity levels above 0.6. The critical moisture contents were detected around 10% for pink salmon heads and were around 15% for Pacific cod heads to reduce water activity levels below 0.6 in these products. The applicable drying temperatures of 50°C lasting over 50 hours for pink salmon heads and 50°C for over 24 hours followed by 30°C for over 24 hours for Pacific cod heads were found optimal. Dried Pacific cod heads showed shelf stability as a potential dried seafood product. Frozen pink salmon heads had 60 days shelf life, while heads with antioxidant glazing retarded oxidation levels (p <0.05). The antioxidant treatment in dried pink salmon heads kept oxidation levels lower than the acceptable limit up to 60 days. This study provided essential information to improve the utilization of these Alaskan seafood byproducts.