• Daily Energy Budgets Of Caribou: A Simulation Approach (Energetics, Metabolism, Rangifer Tarandus, Migration)

      Fancy, Steven Glen (1986)
      Energetic constraints have played a major role in the evolution of caribou (Rangifer tarandus). This thesis discusses several ways in which these constraints have affected caribou morphology, physiology and behavior through their effects on the physiological condition of caribou. A computer model of daily energy budgets was used to simulate energy budgets of caribou in late winter, spring migration, and during the month of July when caribou may be harassed frequently by insects. Model outputs included estimates of metabolizable energy intake, and changes in body weight and body composition. Several of the model inputs, such as fasting metabolic rates and activity costs, were measured using captive caribou. The mean energy cost for locomotion by adult caribou was the lowest recorded for any terrestrial species, and was more strongly related to leg length than to body weight. Highly significant (p < 0.001) relationships between oxygen consumption and heart rates were used to estimate energy expenditures for activities from heart rates of caribou ranging within a large enclosure. Energy expenditures by caribou while feeding on grain at a trough, grazing, browsing and walking, as estimated from heart rates, were 12%, 18%, 18% and 46% higher than that while standing, respectively. The doubly labeled water method was validated using caribou and reindeer as a method for estimating energy expenditures by free-ranging ruminants. The computer model accurately predicted changes in body weight and composition in trials with captive caribou. The model predicted fat losses of approximately 4 kg for pregnant females of the Porcupine Herd during spring migration. During the insect season, a lactating female was predicted to be in negative energy balance on all days when insect harassment occurred for 12 h or longer. Variations in input data associated with energy intake had a much greater effect on model outputs than did factors associated with energy expenditure. Consequently, the optimal range use strategy in the absence of other constraints should involve movements to areas where the most digestible forages can be obtained and the highest eating rates attained.
    • Daily heterogeneity in habitat selection by the Porcupine Caribou Herd during calving

      Jones, Rachel Rands (2005-08)
      Caribou exhibit scale-dependent habitat selection, but variance in daily habitat selection by the Porcupine Caribou Herd (PCH) has not been examined. Investigating temporal variance in habitat selection may clarify the time period when managers may accurately estimate calving-related habitat selection. Annually, 1992-1994, approximately 70 calves were radio-collared within 2 days of birth and relocated daily until departing the calving grounds. We used daily 99% fixed kernel utilization distributions (UD's) to estimate caribou distributions, then estimated daily habitat selection using logistic regression. Habitat variables included relative vegetation greenness, greening rate, landcover class, and elevation. Spatial scales of investigation included concentrated vs. peripheral use within daily UD's, daily use within the merged extent of all daily UD's, and daily use within the historical extent of calving, 1983-2001. We used linear regression of logistic regression parameter estimates on sequential sampling days to estimate temporal habitat selection trends during the 3 weeks following capture. Overall, caribou exhibited habitat selection at multiple scales, without temporal trends, suggesting that the 21-day period following capture constituted a single domain and that managers may accurately estimate calving-related habitat selection at any point during this period.
    • Daily Meal Patterns, Voluntary Food Intake And Fattening Of Reindeer During Winter And Responses To Insulin

      Stimmelmayr, Raphaela; White, R. G.; Drew, K. L. (2001)
      I determined the effect of insulin injections on daily feeding behavior and voluntary food intake (VFI) in reindeer (Rangifer tarandus t. ) fed a concentrate ration during winter. Food intake in the absence of insulin injections was down regulated and characterized by small, regular meals during daylight and irregular and sometimes large nighttime meals. Each large nighttime meal was associated with a long post-meal interval. Daytime meal size could be predicted from an estimate of the energy deficit incurred since the previous meal; however, the occasional oversized nighttime meals were not predicted from energy deficit and suggested that appetite may be deregulated at night. I hypothesized that a low daily dose of long acting insulin (1.0 IU/kg BW, s.c.) would result in regular feeding day and night, which should result in reduced VFI. Changes in serum insulin concentration could not be detected following insulin treatment, however exogenous insulin resulted in a loss of daytime and nighttime differences in meal size and intermeal interval length and a decrease in mean daily meal size. Over a 21 d treatment period, exogenous insulin prevented an increase in VFI during a warming trend and tended to counter a linear decline in body mass and backfat depth (measured by ultra-sound) typified by control animals (given Lactate Ringer 0.005 ml/kg BW, s.c.). The influence of insulin over fat retention suggests that reindeer are capable of lipogenesis in winter. A combination of rhythmic variation in satiety response to meals during daylight and decoupling of meal size and frequency at night is suggested as an endocrine model underlying daily appetite regulation in the reindeer.
    • "Dance, dance, dance: Alaska stories"

      Wise, Zoë E.; Soos, Frank; Johnson, Sara; Heyne, Eric (2019-05)
      Dance, Dance, Dance: Alaska Stories is a collection of young women's coming of age stories. The protagonists range in age from teenager to middle aged, and the circumstances that provoke their epiphanies include events spanning from the mundane to the dramatic, such as looking through a photo album, and death. Protagonists who move through these cumulative events seek to emerge from past identities and understandings of themselves. In all of these stories the Alaskan setting is important. Physical environment, in some stories, is only perceived to be a barrier; in other stories, the setting functions as a conflict that frustrates characters' desires. Regardless, all protagonists, to a degree, ultimately realize themselves to be a barrier, and must overcome internal conflicts before coming to terms with--or abandoning--their external environment. A technical aspect of these stories that I have particularly focused on developing is the varied point of view. The ranges of points of view in these stories include retrospective first person, second person, and third person limited. In this collection I focused on the irony that each point of view, when working with a coming of age story, can provide. Narrative distance in these stories is used to highlight the difference between what the characters know and understand and what we, the readers, understand about their situations
    • Dance/movement therapy (DMT) for cancer survivors and caregivers in Fairbanks, Alaska

      Sharma, Dinghy Kristine B.; Lopez, Ellen D. S.; Rivkin, Inna D.; Swift, Joshua K.; Goodill, Sharon W. (2016-08)
      Worldwide, the burden of cancer continues to grow and impact the quality of life of patients, their families, and caregivers. Aside from the physical effects and financial costs of cancer and its treatment, a significant portion of cancer patients and their caregivers experience emotional, social, and psychological distress throughout the trajectory of their illness and extending to long-term survivorship. Despite medical advances in cancer treatment, a cancer diagnosis is still often considered to be synonymous with death, pain, and suffering. It has been established that engaging in the creative arts could promote quality of life (QOL) especially for those suffering from chronic illnesses such as cancer. Specifically, studies on dance/movement therapy (DMT) have indicated its efficacy as a complementary and holistic intervention in providing social support, decreasing fatigue and stress, increasing mobility, and enhancing overall wellbeing of cancer survivors. Results from a pilot DMT study that explored the cultural suitability, feasibility, and benefits of using DMT in the post-treatment QOL of Alaska Native cancer survivors indicated positive impacts on participants' mobility, body awareness, emotional expression, self-care, and wellbeing. Participants from the pilot study highlighted the need for providing DMT in the community and opening the DMT group to both cancer survivors and caregivers. This suggestion was in consideration of the lack of support groups available to both cancer survivors and caregivers that focus on cancer survivorship and promotion of quality of life. Existing locally available cancer support groups emphasize cancer education but are limited in meeting the psycho-social, emotional and physical needs of both cancer survivors and caregivers. The encouraging results and feedback from participants not only supported existing studies on DMT's cross-cultural benefits in promoting QOL among cancer survivors but also provided the rationale for a larger dissertation study for survivors and caregivers in Fairbanks, Alaska. It was in this context that DMT's significance in increased survivorship and QOL among cancer survivors and caregivers in Alaska was examined. The study employed a sequential, mixed methods small-N design in investigating the therapeutic benefits of DMT among cancer survivors and caregivers (N = 16) in a practice-based setting in Fairbanks, Alaska. Adhering to the principles of community-based partnership research (CBPR), the study established a collaborative partnership with the Fairbanks Memorial Hospital as it piloted a 12- week, open DMT group intervention for cancer survivors and caregivers. The study was conducted in two phases: Phase 1: DMT Intervention (12 weeks) and Phase 2: Follow-up and Findings Meeting (3 months after the last offered DMT session), which assessed DMT’s lasting effects on participants. Quantitative and qualitative data were employed to examine DMT’s effects on participant’s mental health functioning, body awareness, subjective QOL, and sense of group cohesiveness and engagement with the DMT group. Quantitative findings indicated significant improvements in participants’ mental health functioning with a moderate effect size after participation in the DMT program. Although no significant pre- to post-change was found on participants’ subjective QOL, cancer survivors reported significantly better QOL (social, emotional and functional wellbeing) at the three-month follow-up, suggesting that DMT can offer late, but possibly lasting, positive changes. Additionally, participants’ ability for selfregulation and use of avoidance as a coping tool for pain were found to increase after their DMT participation. No significant changes were noted in participants’ level of cohesion with the DMT group. However, qualitative findings indicate that participants found that the DMT program was extremely beneficial in promoting their physical, psychological, social and spiritual wellbeing and expressed overall strong positive feelings toward their DMT group. Implications for research and clinic practice were discussed as informed by the study’s strengths and limitations. One the study’s strengths is its adherence to the principles of community-based participatory research (CBPR) as an over-arching framework in guiding all aspects of the research process. By establishing a collaborative partnership between the UAF academic community and the local community hospital (Fairbanks Memorial Hospital), this study was able to build on the community’s strengths and resources in an effort to help promote cancer survivorship for cancer survivors and caregivers. Future recommendations include further strengthening collaborative community partnerships with a larger, DMT confirmatory study using a Randomized Control Trial (RCT) design, while integrating a mixed-methods approach. Implementing these strategies would help establish DMT’s efficacy as a holistic and ecologically valid intervention for cancer survivors and caregivers in Fairbanks, Alaska.
    • Data analysis and data assimilation of Arctic Ocean observations

      Stroh, Jacob Nathaniel; Panteleev, Gleb; Mölders, Nicole; Weingartner, Thomas; Rhodes, John (2019-05)
      Arctic-region observations are sparse and represent only a small portion of the physical state of nature. It is therefore essential to maximize the information content of observations and bservation-conditioned analyses whenever possible, including the quantification of their accuracy. The four largely disparate works presented here emphasize observation analysis and assimilation in the context of the Arctic Ocean (AO). These studies focus on the relationship between observational data/products, numerical models based on physical processes, and the use of such data to constrain and inform those products/models to di_erent ends. The first part comprises Chapters 1 and 2 which revolve around oceanographic observations collected during the International Polar Year (IPY) program of 2007-2009. Chapter 1 validates pan- Arctic satellite-based sea surface temperature and salinity products against these data to establish important estimates of product reliability in terms of bias and bias-adjusted standard errors. It establishes practical regional reliability for these products which are often used in modeling and climatological applications, and provides some guidance for improving them. Chapter 2 constructs a gridded full-depth snapshot of the AO during the IPY to visually outline recent, previouslydocumented AO watermass distribution changes by comparing it to a historical climatology of the latter 20th century derived from private Russian data. It provides an expository review of literature documenting major AO climate changes and augments them with additional changes in freshwater distribution and sea surface height in the Chukchi and Bering Seas. The last two chapters present work focused on the application of data assimilation (DA) methodologies, and constitute the second part of this thesis focused on the synthesis of numerical modeling and observational data. Chapter 3 presents a novel approach to sea ice model trajectory optimization whereby spatially-variable sea ice rheology parameter distributions provide the additional model flexibility needed to assimilate observable components of the sea ice state. The study employs a toy 1D model to demonstrate the practical benefits of the approach and serves as a proof-of-concept to justify the considerable effort needed to extend the approach to 2D. Chapter 4 combines an ice-free model of the Chukchi Sea with a modified ensemble filter to develop a DA system which would be suitable for operational forecasting and monitoring the region in support of oil spill mitigation. The method improves the assimilation of non-Gaussian asynchronous surface current observations beyond the traditional approach.
    • Data mining for mine-mill ore grade reconciliation at Erdenet Mining Corporation

      Sarantsatsral, Narmandakh (2016-11)
      This project investigates the relationship between the mined ore and the produced copper at the Erdenet Mining Corporation (EMC) surface copper mine in Mongolia. Four and half years of data (from 2011-2015) was obtained from the open pit mine and mineral processing plant of EMC. The mine-mill data was collected on a shift basis. The data was examined carefully using process knowledge and exploratory data analysis techniques to detect and eliminate errors. Ultimately, two years of data (2013-2014) was selected for further analysis. As is common in all mines, the material flow between the mine and mill is complicated by numerous stockpiles. The copper grade going into a stockpile may not be directly related to the copper grade exiting a stockpile. Therefore, data mining techniques applied to detect the relationship between mined ore and milled copper had to overcome the complications introduced by the presence of stockpiles. Multiple data sets were created by aggregating the original dataset by different periods. For example, in one case, data was aggregated by three shifts, to convert the data from shift-basis to daily-basis. Aggregation is an ideal way to absorb variations in material flow (tonnage and grade) between mine and mill. Data was aggregated by 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12 shifts ("aggregated widths" or AW). Correlation analysis was then conducted on each version of the data to determine if a relationship existed between mine data and mill data. Correlation was computed for various period lengths, but not exceeding 28 days. Therefore, in a given year, several correlation plots were produced at each aggregated width. The number of times the correlation coefficient exceeded 0.8 in a year was measured. Results showed that correlation improved with aggregation width. The highest correlations occurred at AW of 7 or 8. This suggests that the stockpiles aggregate material for 2-3 days. Correlation analysis also included examining a time shift ("lag") between mine data and mill data. This is useful to detect whether material takes a certain amount of time before it is processed and produced as copper. However, results indicated that once the data was aggregated, a time lag greater than 0 only worsened correlation.
    • Davix: a toolset for data analysis and visualization

      Gellhouse, Amanda L.; Nance, Kara; Hay, Brian; Genetti, Jon (2014-04)
    • Deactivation and excitation of 0I(6s ⁵S) at above-thermal energies

      Enzweiler, Joseph A. (1982-05)
      Absolute collisional deactivation and excitation cross sections have been measured for a beam of O (⁵P-⁵S°) incident on N₂. The beam energy was varied from 3.95 to 10.65 keV. Cross sections for charge transfer (electron capture) of 0⁺ in N₂ were also measured in the energy range from 2.4 to 24.3 keV. The variation of light intensity 5436 Å (from the 6s-3p transition of the quintet system of atomic oxygen) emitted from the beam as a function of N₂ target pressure was fitted to a beam of kinetic equation to determine deactivation and excitation cross sections. The cross section for deactivation in N₂ decreases from 6.84 x 10⁻¹⁵ cm² at 3.95 keV to 1.5 x 10⁻¹⁵ cm² at 19.65 keV. The cross section for excitation decreases from 3.3 x 10⁻¹⁹ at 3.95 keV to 2.25 x 10⁻¹⁹ cm² at 19.65 keV.
    • The deadly affairs of John Figaro Newton or a senseless appeal to reason and an elegy for the dreaming

      Campbell, Regan; Farmer, Daryl; Kamerling, Leonard; Coffman, Chris (2020-05)
      Are you really you? Are your memories true? John "Fig" Newton thinks much the same as you do. But in three separate episodes of his life, he comes to see things are a little more strange and less straightforward than everyone around him has been inured to the point of pretending they are; maybe it's all some kind of bizarre form of torture for someone with the misfortune of assuming they embody a real and actual person. Whatever the case, Fig is sure he can't trust that truth exists, and over the course of his many doomed relationships and professional foibles, he continually strives to find another like him--someone incandescent with rage, and preferably, as insane and beautiful as he.
    • Dealing with uncertainties in integrated age-structured assessment models

      Hulson, Peter-John F.; Quinn, Terrance II; Norcross, Brenda; Marty, Gary; Adkison, Milo; Hanselman, Dana (2012-05)
      Dealing with uncertainties in integrated age-structured assessment (ASA) models has become a central focus at all levels of fish stock assessment and management. My goal in this thesis was to uncover layers of uncertainty in ASA models. There were two major components to this approach: (1) dealing with uncertainty in datasets used in ASA models through examining effective sample size, and (2) dealing with uncertainty in ASA model structure through examination of effective number of parameters and simulations of school and stock structure. From the dataset uncertainty perspective, I investigated age and length composition datasets by first identifying possible sources of error and then by evaluating if it is feasible to include this error within ASA models. From the structural uncertainty perspective, I compared historical ASA models with spatially-explicit and metapopulation scale ASA models. Sources of uncertainty in age and length composition datasets include the spatial distribution of schools and age aggregation of fish within schools. To account partially for this error at the survey design level, the optimal approach is to sample from a greater number of schools, even if the sample size within any particular school is reduced. Also, it is possible to include this error within ASA models by parameterizing and estimating effective sample size with the Dirichlet distribution. Reduced uncertainty in parameters and management quantities resulted from spatially-explicit and metapopulation ASA models when compared to historical ASA model structures. Further, with possible climate change influences on fish populations use of spatially-explicit and metapopulation ASA models will allow stock assessment scientists to accurately and more precisely predict sustainable harvest levels.
    • Decadal scale vegetation maps for the boreal forest surrounding Fairbanks, Alaska

      Huhman, Hannah E.; Prakash, Anupma; Rosselló, Jordi Cristóbal; Dewitz, Jon (2018-08)
      Vegetation maps of a selected area within the boreal forest surrounding Fairbanks, Alaska, have been generated for the nominal years of 1985, 1995, 2005, and 2015 using Landsat 4 and 5 Thematic Mapper and Landsat 8 Operational Land Imager surface reflectance products at 30 meter spatial resolution using a decision tree classification. The maps include 9 U.S. Geological Survey (USGS) vegetation classes, as well as barren land, open water, and ice/snow classes that are consistent with the classes identified in the 2001 National Land Cover Database (NLCD) map of Alaska generated by the USGS. Classification steps are based on USGS methodology, with refinements for the boreal forest, to ensure further comparison to the 2001 USGS NLCD map for Alaska. The overall weighted accuracies of first order estimates of data quality using cross validation are 93.2%, 88.4%, 93.3%, and 86.9% for the nominal years of 1985, 1995, 2005, and 2015 maps, respectively, compared to 81.8% accuracy for the USGS NLCD 2001 product. This study demonstrates that the spatial and spectral resolution of Landsat data is the best available for mapping the vegetation of Alaska's boreal forest at 1:50,000 scale. It also shows that the boreal forests surrounding Fairbanks, Alaska have witnessed a decrease in the growth of evergreen forests, an expansion of shrub and an increase in wetland distribution, all of which have been reported as impacts of a warming climate in the Arctic and Sub-arctic.
    • Decadal Variability In The Arctic Ocean: Greenland-Iceland-Norwegian Seas Ice-Ocean-Atmosphere Climate System

      Dukhovskoy, Dmitry Stanislavovich; Johnson, Mark; Proshutinsky, Andrey (2003)
      This study investigates the decadal variability of the Arctic Ocean---Greenland, Iceland, Norwegian Seas (GIN Sea) system and possible mechanisms driving variability. The theoretical foundation of this work is the theory of Proshutinsky & Johnson [1997] that two major climate states of the Arctic---Anticyclonic Circulation Regime (ACCR) and Cyclonic Circulation Regime (CCR)---are driven by variations in the freshwater contents of the Arctic Ocean and the GIN Sea. It is hypothesized that the Arctic Ocean and the GIN Sea form an auto-oscillatory ice-ocean-atmosphere climate system with a quasi-decadal period of interannual variability. The system is characterized by two stages: (1) cold Arctic (ACCR)---warm GIN Sea with weak interaction between the basins; (2) warm Arctic (CCR)---cold GIN Sea with intense interaction between the basins. Surface air temperature and dynamic height gradients between the basins drive the auto-oscillations. This study investigates interactions between the Arctic Ocean and the GIN Sea. To test the hypothesis, a simple model of the Arctic Ocean and Greenland Sea has been developed. The Arctic shelf processes have been parameterized in a box model coupled with an Arctic Ocean module. Both the Arctic Ocean and Greenland Sea modules are coupled with a thermodynamic ice model and atmospheric models. Several model experiments have been conducted to adjust the model and to reproduce the auto-oscillatory behavior of the climate system. One of the major results of this work is the simulation of auto-oscillatory behavior of the Arctic Ocean---GIN Sea climate system. Periodical solutions obtained with seasonally varying forcing for scenarios with high and low interaction between the regions reproduce major anomalies in the ocean thermohaline structure, sea ice volume, and fresh water fluxes attributed to ACCR and CCR regimes. According to the simulation results, the characteristic time scale of the Arctic Ocean---GIN Sea system variability reproduced in the model is about 10--15 years. This outcome is consistent with theory of Proshutinsky and Johnson [1997] and shows that the Arctic Ocean---GIN Sea can be viewed as a unique auto-oscillating system.
    • Deciphering Okmok Volcano's restless years (2002-2005)

      Reyes, Celso Guillermo; McNutt, Stephen; West, Michael; Freymueller, Jeffrey; Larsen, Jessica (2015-08)
      Okmok Volcano is an active island-arc shield volcano located in the central Aleutian islands of Alaska. It is defined by a 10-km-diameter caldera that formed in two cataclysmic eruptions, the most recent being ~2050 years ago. Subsequent eruptions created several cinder cones within the caldera. The youngest of these, Cone A, was the active vent from 1815 through its 1997 eruption. On July 12 2008 Okmok erupted from new vents located northwest of Cone D. Between 2001 and 2004, geodetic measurements showed caldera inflation. These studies suggested that new magma might be entering the system. In 2002, a newly installed seismic network recorded quasi-periodic ("banded") seismic tremor signals occurring at the rate of two or more episodes per hour. This tremor was a near-continuous signal from the day the seismic network was installed. Although the volcano was not erupting, it was clearly in a state of unrest. This unrest garnered considerable attention because the volcano had erupted just six years prior. The seismic tremor potentially held insight as to whether the unrest was a remnant of the 1997 eruption, or whether it signaled a possible rejuvenation of activity and the potential for eruption. To determine the root cause and implications of this remarkable seismic tremor sequence, I created a catalog of over ~17,000 tremor events recorded between 2003 and mid-2005. Tremor patterns evolved on the scale of days, but remained the dominant seismic signal. In order to facilitate the analysis of several years of data I created a MATLAB toolbox, known as "The Waveform Suite". This toolbox made it feasible for me to work with several years of digital data and forego my introductory analyses that were based on paper "helicorder" records. I first attempted to locate the tremor using the relative amplitudes of the seismograms to determine where the tremor was being created. Candidate tremor locations were constrained to a few locations along a corridor between Cone A and the caldera center. I then determined theoretical ratios between a reference station and stations nearby the candidate sources. Results suggested that the signal originated in the shallow portion of the corridor connecting the surface of Cone A to the top of the central magma chamber. This study also suggested that the source migrated along this corridor. I integrated the tremor patterns with other studies and proposed that heat and pressure from continued injections of magma were responsible for maintaining an open venting system at Cone A. The tremor resulted from the boiling of a shallow hydrothermal system in the vicinity of Cone A and volatiles potentially coming from the magma itself. The tremor catalog demonstrates that the seismic signal waned during the study period suggesting that fewer fresh volatiles entered the system, which may have allowed the pathways connecting the magma and volatiles to the surface to close up. By the time new magma entered the system in 2006, this network of pathways was closed, forcing the volatiles to seek a new exit. In hindsight, the 2003-2005 period of varied and waning seismic tremor, and the inferred end of massive open venting, may have been a pivotal era at Okmok that eventually led to the 2008 eruption.
    • The decision-making process of first year teachers

      Coskey, Isabeau S. (2015-08)
      Attrition rates among beginning teachers have long been a cause for concern. As a profession, teaching is one that is extremely difficult to enter into and find your footing. For most novice teachers the first year of teaching is typically the most difficult due to the challenges faced both in the classroom and personally. During the day a myriad of decisions fall on the shoulders of a teacher and long after students have gone most teachers are continuing to make decisions about the classroom. This project examines the major areas where decisions are being made, charts the decision-making process first year teachers employ, and presents an electronic guidebook that can be used by individuals transitioning from a pre-service program into their first year of teaching.
    • Decline curve analysis and enhanced shale oil recovery based on Eagle Ford Shale data

      Delaihdem, Dieudonne K.; Dandekar, Abhijit; Ahmadi, Mohabbat; Hanks, Catherine (2013-12)
      Transient and fracture dominated flow regimes in tight permeability shale reservoirs with hydraulically fractured horizontal wells impose many unconventional challenges. These include execution of appropriate shale decline curve analysis and the optimization of hydrocarbons recovery. Additionally, short production profiles available are inadequate for accurate production decline analysis. This research assessed the effectiveness of Arps' decline curve analysis and recently established methods--power law exponential analysis, logistic growth analysis, Duong's method and the author's approach--to predict future production of horizontal wells in the Eagle Ford Shale. Simulation models investigated history matching, enhanced shale oil recovery, and drainage area beyond stimulated reservoir volume. Traditional Arps' hyperbolic method sufficiently analyzed past production rates, but inaccurately forecasted cumulative productions. The recent decline models show slight variations in their past performance evaluations and forecasting future production trends. The technique proposed and used in this work enhanced the successful application of Arps' hyperbolic decline from 32.5% to 80%. Simulation results indicate 4.0% primary oil recovery factor and 5.8% enhanced shale oil recovery factor using CO��� miscible injection. Based on pressure observed outside of the stimulated reservoir volume, limited to the range of data used in this study, drainage area outside stimulated reservoir volume is not significant.
    • Decomposition and adsorption of peptides in Alaskan coastal marine sediments

      Luo, Honghong (1994)
      In organic-rich coastal sediments, hydrolyzable amino acids make up a substantial fraction of the sedimentary content of organic nitrogen. How this organic nitrogen resists decomposition and is preserved in sediments is poorly understood. In order to investigate the factors controlling mineralization and preservation of hydrolyzable amino acids, decomposition and adsorption of peptides were studied in suboxic and anoxic pore water and sediments from Resurrection Bay (RB) and Skan Bay (SB), Alaska. Five tritium-labeled peptides, basic di-lysine, acidic di-glutamic acid, and neutral di-alanine, tri-alanine and hexa-alanine, were used as tracers. In filtered pore water, the hydrolysis rates were usually low. The exception was that the initial enzymatic hydrolysis of di-alanine and di-glutamic acid was rapid in SB pore water. The hydrolysis rates of both peptides increased with concentration. In sediments, hydrolysis was found to be the rate-limiting step of peptide decomposition. Alanyl and glutamyl peptides were hydrolyzed faster than lysyl peptide, and the hydrolysis rates among alanyl peptides decreased with increasing molecular weight. Peptide hydrolysis was affected more by molecular structure than by oxic or anoxic conditions. Adsorption of lysyl peptide to sediments was greater than that of other peptides. Basicity enhanced peptide adsorption more than increased molecular weight. Sedimentary organic matter was mainly responsible for peptide adsorption. The different patterns of peptide adsorption in RB and SB sediments were related to the greater total organic carbon concentration in SB sediment. Some of the peptide adsorption was irreversible. Adsorbed peptides were more resistant to biological decomposition than dissolved peptides. Adsorption may be an important step in the process of peptide preservation in sediments, and thus the preservation of sediment organic matter during early diagenesis.
    • Decomposition of dissolved organic matter in Arctic and boreal streams

      Mutschlecner, Audrey; Harms, Tamara; Jones, Jeremy; Guerard, Jennifer (2017-05)
      Arctic and boreal rivers connect terrestrial, oceanic, and atmospheric carbon (C) pools by transporting and processing dissolved organic matter (DOM). DOM composition influences its susceptibility to decomposition (biolability), which in turn determines whether the associated C is respired, stored, or exported. High-latitude ecosystems are changing rapidly due to processes such as permafrost thaw, shifts in vegetative communities, and increasing discharge, and each of these processes can influence the composition of DOM reaching rivers. The eventual fate of riverine DOM, whether it is mineralized or exported, shifts the balance of global C pools. Therefore, to understand how changes to high-latitude ecosystems influence the global C cycle, we must be able to connect patterns in DOM composition to its biolability and subsequent fate within the C cycle. The objectives of this study were to describe spatial and temporal patterns in DOM composition and biolability, and to determine links between the composition and biolability of DOM. I sampled DOM from streams along an Arctic-boreal gradient in interior Alaska throughout the year. I measured DOM biolability and nutrient limitation of decomposition in laboratory incubations and characterized DOM composition using optical properties and chemical analysis. I found that temporal patterns in DOM composition corresponded to seasonal trends in the hydrology of high-latitude catchments, linking DOM source to shallow, organic-rich flowpaths in spring and deeper groundwater flows in winter. Biolability was low, indicating that the majority of riverine DOM is recalcitrant to biological decomposition. I observed increased biolability in response to phosphorus (P) addition, particularly during spring, indicating that phosphorus limits DOM decomposition. To further examine the mechanisms driving C processing in streams, I also conducted a series of whole-stream experiments to compare the relative influence of molecular composition and nutrient content of DOM. I added leaf leachate to boreal streams and measured C retention, which represents both biological uptake and sorption. The leachates varied by molecular composition, due to differences in tissue chemistry of plant species, and in nutrient content, because the leaves were collected from plots with different fertilization regimes. Retention was greatest for leachates derived from trees that had been fertilized with P, indicating P-limitation of biological uptake of C or preferential sorption of P-containing organic molecules. Although leachates varied in molecular composition as determined by optical properties, these differences did not correspond to a difference in uptake rates by species. These patterns in DOM retention indicate that nutrient content is a greater constraint on C uptake than molecular composition. Together, the two studies suggest that export is the primary fate of ambient DOM in high-latitude streams, but that C processing is highly sensitive to inputs of bioavailable DOM. The coupling between the P and C cycles observed in both studies highlights the potential for nutrient availability to constrain or promote CO₂ emissions from C-rich, high-latitude catchments.
    • Decompression induced crystallization of basaltic andesite magma: constraints on the eruption of Arenal volcano, Costa Rica

      Szramek, Lindsay Ann (2004-08)
      Continuously active since 1968, Arenal Volcano in Costa Rica has undergone various eruption styles. The deposited magmas, whereas geochemically similar, show a complex history of magma chamber processes, which are not fully understood. The intricate mixing histories of the phenocrysts and lack of oxide pairs have made determination of the volatile content and oxygen fugacity difficult by conventional methods. Phase equilibria experiments were carried out between 200-50 MPa and 940-1075°C in a TZM furnace at fO₂ of NNO and water saturation. Time in the furnace varied from 7 to 30 hours at constant pressure and temperature. Examination of the natural and experimental phase assemblages constrained the probable pre-eruptive conditions for Arenal magmas to be 50-80 MPa and 950-1040°C. For decompression experiments, the sample was initially held at two conditions 200MPa and 950°C and 60MPa and 1050°C. The samples were then decompressed by 5-30 MPa pressure steps held for 20 seconds to 8 hours until 20 MPa was reached, approximating average decompression rates of 0.25, 0.025, and 0.0013 MPa/s. Textures formed in the experiments and seen in the natural samples constrain the probable ascent rate of the Arenal magma to 0.05 mls. The ascent rate increases as explosivity increases.
    • Deconstructing the western worldview: toward the repatriation and indigenization of wellness

      Rahm, Jacqueline Marie; Koskey, Michael; Lewis, Jordan; John, Theresa; Leonard, Beth (2014-12)
      As Indigenous peoples and scholars advance Native histories, cultures, and languages, there is a critical need to support these efforts by deconstructing the western worldview in a concerted effort to learn from indigenous knowledge and ways of knowing for humanity's future wellbeing. Toward that imperative, this research brings together and examines pieces of the western story as they intersect with Indigenous peoples of the lands that now comprise the United States of America. Through indigenous frameworks and methodologies, it explores a forgotten epistemology of the pre-Socratic and Pythagorean Archaic and Classical Greek eras that is far more similar to indigenous worldviews than it is to the western paradigm today. It traces how the West left behind this timeless wisdom for the "new learning" and the European colonial settlers arrived in the old "New World" with a fragmented, materialistic, and dualistic worldview that was the antithesis to those of Indigenous peoples. An imbalanced and privileged worldview not only justified an unacknowledged genocide in world history, it is characteristic of a psycho-spiritual disease that plays out across our global society. This dissertation suggests that the healing of the western mind rests with shifting the dominant paradigm toward a fundamental axiom of holism found within the life-ways of American Indigenous peoples and also buried within the West's own ancestry, particularly within a misunderstood ancient Greek tradition at the cornerstone of the western world.