• Beyond trending: using risking connection as a framework for moving agency culture toward trauma-informed care

      Healey, Michael J.; Renes, Susan L.; Strange, Anthony; Baker, Courtney; Anahita, Sine (2020-08)
      The prevalence and pervasive impact of adverse childhood experiences (ACEs), and more broadly, trauma, are well supported in the extant literature. Despite this evidence, there remains a significant dearth of formal training and educational programs that prepare staff who work with trauma survivors within complex behavioral health systems. Trauma-informed care (TIC) has moved beyond a trend in the mental health field and is gaining momentum as a leading philosophical paradigm that is being infused as an operational framework for agencies that work with survivors. Risking Connection (RC) is a curriculum-based training program that works with agencies interested in becoming trauma-informed. The current study examined the impact of RC on trainee outcomes for knowledge gain, attitude change, and vicarious trauma (VT) on 119 participants who all work for a therapeutic group home system being operated by a provincial government in Atlantic Canada. The findings in this study suggest that RC is effective in improving knowledge gain and attitude change in a favorable direction toward TIC. The study also supported previous findings associated with the improvement of VT.
    • Blood falls, Taylor Glacier, Antarctica: subglacially-sourced outflow at the surface of a cold polar glacier as recorded by time-lapse photography, seismic data, and historical observations

      Carr, Chris G.; Pettit, Erin; Carmichael, Joshua; Truffer, Martin; Tape, Carl (2021-05)
      Blood Falls forms when iron-rich, hypersaline, subglacially-sourced brine flows from a crack in the surface of Taylor Glacier, Antarctica. If air temperatures are low enough, the brine freezes to form a fan-shaped icing deposit. In chapter two, historical observations (including photos, oral histories, written descriptions, and field sketches) are evaluated using a confidence assessment framework to compile a history of brine icing deposit presence or absence during summer field seasons between 1903-1904 and 1993-1994. Additionally, an alternative explanation for a small, localized advance of a portion of the terminus is proposed: rather than temperature-driven ice viscosity changes, rising lake level drove temporary, localized basal sliding which induced advance, thinning, and collapse of a part of the terminus previously grounded on a proglacial moraine. In chapter three, time-lapse imagery is used to document a 2014 wintertime brine release that occurred in the absence of surface melt. This suggests that meltwater-driven fracture propagation of surface crevasses downward into the glacier was not a likely factor in this brine release event, as has been previously proposed. Further, there is no evidence for an increase in Rayleigh-wave activity prior to or during the brine release that would be characteristic of shallow seismic sources. Together, this suggests that sufficient pressure is built in the subglacial system to trigger basal crevassing and fracture propagation upward to allow brine release at the surface. In chapter four, two different seismic detectors that use ratios of short-term to long-term seismic energy variance to identify seismic events are compared. The detectors use different statistical distributions to determine what constitutes a large enough ratio to trigger an event detection. Differences between what the two detectors identify as events rather than background noise are interpreted as environmental microseismicity with a distinct diurnal and seasonal occurrence. Minimum detectable event sizes over 3-day time windows are compared. Together, these studies provide context for the history of brine release events, wintertime brine release characteristics, and descriptions of the local seismic environment at Taylor Glacier.
    • Born to burn: characterizing fuel loads, flammability and plant traits across spatio-temporal gradients of black spruce dominated communities

      Grzesik, Emilia J.; Ruess, Roger; Hollingsworth, Teresa; Turetsky, Merritt (2020-12)
      The flammability of black spruce forests is influenced by the fuel loadings and quality of fuels within a site, whereas the ability of a site to self-replace after fire, and thus forest resiliency, depends on the fire-ecological trait attributes of the plant community. Black spruce plant communities have been undergoing self-replacement succession from low to moderate severity fires for thousands of years, however, recent intensification of interior Alaska's fire regime is leading to shifts in post-fire successional trajectories, resulting in many ecological implications. This study focuses on understanding the variation in black spruce forest flammability, based on fuel load quantity and quality, and fire-ecological plant traits in 28 black spruce dominated sites ranging across age and moisture gradients in interior Alaska. I quantified tree canopy, understory and below-ground fuel loads, developed models to predict fuel loads and then utilized my measurements of above-ground fuel load quantity and quality to calculate a site-level flammability index. Based on my analyses, significantly greater flammability indices, and thus burning potential, occur in sites greater than 34 years in age, at elevations greater than 302 m and with dry site moisture, which are representative of dry, nonacidic upland black spruce and dry, acidic upland black spruce-lichen forest ecosystems. Furthermore, although fire-ecological plant trait attributes of Hylocomium splendens and Vaccinium uliginosum vary with age and moisture gradients, the amount of intra-specific trait variation within a site could not be explained by stand age or moisture and thus forest resiliency is also likely independent of age and moisture gradients. Further research is necessary to explore both abiotic and biotic explanatory variables related to intra-specific plant trait variation to better understand variation in black spruce forest resiliency on the landscape. The results from this study can assist fire managers in the prediction of black spruce forest burning potential and its vulnerability to ecosystem shift post-fire.
    • Bristol Bay dual permit operations, vessel heterogeneity, and the migration of Alaskan permit holders

      Gho, Marcus J.; Criddle, Keith; Adkison, Milo; Adkison, Milo; Twomley, Bruce; Brown, Benjamin (2020-08)
      This dissertation examines three aspects of Alaska's Limited Entry program. Chapter 1 explores the outcome of dual-permit regulations. The Alaska Board of Fisheries passed regulations allowing for dual permit operations in the Bristol Bay Pacific salmon drift gillnet fishery starting in 2004. These regulations allow two permit holders to fish from a single vessel with additional gear. Policymakers anticipated that the dual permit regulations would encourage young fishermen to enter the fishery and reduce the number of limited entry permits transferred from local fishermen to nonlocal fishermen and nonresidents. Statistical analyses reported in Chapter 1 indicate that the dual-permit program successfully offset part of the adverse influence of increases in the market value of permits on the number of new entrants and that implementation of dual-permit regulations was followed by a reduction in the median age of new entrants, particularly among nonresidents. However, the implementation of dual-permit regulation failed to staunch the outflow of limited entry permits. Chapter 2 examines the persistence of heterogeneity in the size of fishing vessels active in the Bristol Bay salmon drift gillnet fishery. When entry was limited, the commercial fishing fleet included a mix of vessels up to the long-established 32-foot maximum length. The race for fish that so often arises under license limitation favors the adoption of vessel and gear configurations that maximize catch-perday and could be anticipated to lead to increased homogeneity in fleet composition. Yet, statistical analyses indicate that even after over four decades, the composition of this fleet remains heterogeneous in vessel size and vessel value. Multivariate analysis of time series observations of vessel values indicates that vessels captained by permit holders who were given their permit are less capitalized than vessels captained by permit holders who purchased their permit. Likewise, vessels operated by local resident permit holders are less capitalized than vessels owned by nonlocal Alaskan or nonresident permit holders. In addition, vessels operated by older permit holders are less capitalized than vessels operated by younger permit holders. Chapter 3 examines the factors that influence the migration of permit holders. Since limitation, there have been concerns that ever more of the permits issued to individuals local to Alaska's fisheries would come to be held by individuals who were not local to the fisheries. The count of permit holders local to a fishery can change because of transfers, administrative cancellations, or because permit holders migrate either to or from fisheries where the permit is used. Chapter 3 considers possible factors that predict permit migration to or from different residency classes. Included in our analysis was a look at season length, fleet participation rates, permit transfers, the size of the fleet, gear type, wages of construction workers to serve as a proxy for substitute employment, and the local unemployment rate. Statistical analyses indicate that fisheries with longer seasons show slightly elevated migration from local to nonresident status of permit holders. Permit latency and permit holder migration have a negative relationship among the significant variables. Transfers serve as a substitute for permit migrations and provide the largest influence on permit migrations. For every resident type of migration, as the transfer rate increases, fewer permit holders migrate. The total number of permits within the fishery also affects the migration of permit holders, albeit only minimally. The second-largest influence on permit migration is gear type. Migrations to local setnet permit holders had a smaller magnitude of change than migrations from permit holders across most categories. Generally speaking, migration tends to move towards a nonresident status of permit holders. Wages of construction workers were only significant at the 5% level for transfers from locals to nonresidents and from nonresidents to locals, but both variables were positive. As the local unemployment rate increases, the rate of locals emigrating outside of Alaska increased.
    • Changing glaciers in the Brooks Range and western Chugach Mountains, Alaska: mass loss, runoff increase, and supraglacial volcanic tephra coverage

      Geck, Jason; Hock, Regine; Coakley, Bernard; Dial, Roman; Loso, Michael (2020-12)
      Glaciers in Alaska cover over ~87,000 km² (~ 6 % of the state) with most glaciers thinning and retreating at an increasing rate. The thinning and retreating of glaciers worldwide can have an immediate socio-economic implication in addition to the longer-term glacier meltwater contribution to sea level rise. This dissertation investigated Alaskan glaciers in the Brooks Range for mass loss and area reductions over the period 1970-2001 (Chapter 2), historic mass balance and runoff for Eklutna Glacier, located in western Chugach Mountains, using a temperature index model over 1984-2019 period (Chapter 3), and the persistence of tephra from a volcanic eruption of Mt. Spurr in 1992 on seven western Chugach Mountain glaciers (Chapter 4). Glaciers in the Brooks Range in Arctic Alaska (> 68° N) are important indicators of climate change and provide information on long-term climate variations in an area that has few high elevation meteorological stations. Digital elevation models (DEMs) reconstructed from topographic maps were differenced from an interferometric synthetic aperture radar DEM to calculate the volume and mass changes of 107 glaciers (42 km²). Over the period 1970-2001, total ice volume loss was 0.69 ± 0.06 km³ corresponding to a mean (area-weighted) specific mass balance rate of -0.54 ± 0.05 m w.e. a⁻¹ (± uncertainty). The arithmetic mean of all glaciers' specific mass balance rates was -0.47 ± 0.27 m w.e. a⁻¹ (± 1 std. dev.). A subsample of 36 glaciers found a 26 ± 16 % mean area reduction over ~35 years. Alaska's largest city, Anchorage, is critically dependent upon the melt water of Eklutna Glacier (29 km²) for both drinking water and hydropower generation; however, the glacier is rapidly retreating. We used a temperature index model to reconstruct the glacier's mass balance for the period 1985-2019 and quantify the impacts of glacier change on runoff. Eklutna Glacier experienced a significant annual mean surface mass balance negative trend (-0.38 m w.e. Decade⁻¹). Mean annual cumulative melt increased by 24 % between the 1985-93 and 2011-19 period. Additionally, the day of the year when 95% of annual melt has occurred was eight days later in the later time period than in the earlier period, demonstrating a prolongation of the melt season. The modeled mean annual discharge increased at a rate of 0.2 m decade⁻¹. This indicates that peak water, i.e. the year when annual discharge starts decreasing as the glacier becomes smaller, has not been reached. The past increases in runoff quantity and melt season length provide opportunities for water resource managers that must be balanced against future decreased runoff as the glacier continues to shrink. Volcanic eruptions deposit volcanic tephra on glaciers in Alaska, modifying surface albedo and glacier melt. We mapped the distribution of tephra originating from the eruption of Mt. Spurr in 1992 using aerial photos and satellite imagery on seven glaciers located approximately 180 km east of the volcano in western Chugach Mountains in southcentral Alaska. The glaciers were completely covered with ≥ 500 g m⁻² tephra immediately after the event. Tephra deposits are still visible on all glaciers 26 years after the eruption. Using LandSat 8 surface reflectance bands, we quantified percentages of tephra glacier coverage. Results suggest an increasing tephra extent on five of the seven investigated glaciers over 2013-2018 period explained by firn line retreat. The mean percent increase for all glaciers was 4% with Troublesome Glacier showing greatest increase (~ 7 %) and Finch Glacier showing a slight decrease (~ 1 %). This long- term tephra persistence on glacier surfaces most likely enhanced melt although the precise effect remains unknown.
    • Characterization of water-soluble brown carbon (WS-BrC) from boreal forest wildfires in the summer season at northern high latitudes

      Banerji, Sujai; Mao, Jingqiu; Simpson, William R.; Guerard, Jennifer J. (2021-05)
      In the current study, we quantify the absorption Ångström exponent (AAE) and the mass absorption coefficient (MAC) of water-soluble brown carbon (WS-BrC) from boreal forest wildfires. We deployed a Particle into Liquid Sampler (PILS) - Liquid Waveguide Capillary Cell (LWCC)-Total Organic Carbon analyzer (TOC) system in downtown Fairbanks during the summer of 2019, to measure the light absorption by WS-BrC between around 200 nm to around 800 nm wavelength range every four minutes, and the concentration of the water-soluble organic carbon (WSOC), every two minutes. We then compute the AAE and MAC to examine the optical properties of brown carbon from boreal forest fires. During this period, several forest fires burned and we sampled particles from these fires. We explored a number of quantitative methods to compute the AAE and find that using the entire wavelength range of 300 nm to 350 nm appears to best represent the wavelength dependence of BrC absorption, in contrast to using just a pair of two wavelengths. The calculated AAE is observed to be ~3 for smaller wildfires and above ~3 for medium and large wildfires, whereas the calculated AAEnew is observed to be ~5 during the sampling of small, medium and large wildfires. The calculated MAC at 365 nm (MAC₃₆₅) tends to be ~1.0 m² g⁻¹ and remains relatively constant during wildfire events. We further compare these values to measurements reported from mid-latitude wildfires, to quantify the difference between the wildfires in Alaska and Canada from that of the wildfires in the contiguous U.S.
    • Climate change, moose, and subsistence harvest in Arctic Alaska

      Zhou, Jiake; Kielland, Knut; Kofinas, Gary; Tape, Ken D.; Prugh, Laura (2020-08)
      Arctic climate is resulting in transformative changes to Arctic social-ecological systems. With warming-induced increases in tall-shrubs, moose are expanding their range northwards. However, the socio-economic implications of this ecological change are unclear. Using field surveys, interviews, and modeling, I assessed the impact of climate change on moose harvest by hunters of Nuiqsut, an Inupiat community in arctic Alaska. Based on a 568 km transect of field sampling on shrubs and herbivore browsing levels, I estimated that the minimum shrub height for moose occurrence was ≥ 81 cm (95% CI: 65 - 96 cm). Patterns of moose geographic distribution mirrored tall-shrub distribution in arctic riparian areas. I also found that snowshoe hares may impact moose habitat via potential resource competition. Habitat suitability models, using Maxent and simpler temperature-threshold models, predicted that moose habitat may more than double by 2099 if current warming trends continue. The model outputs also suggested that climate warming will likely increase habitat connectivity, enhancing range expansion of moose in the Arctic. Finally, I used a coupled social-ecological systems (SES) framework to assess the implications of changes in tall-shrub habitat to moose harvest under future warming. Despite the expected increase in moose habitat and distribution, simulations of an agent-based model showed that the future may not translate into greater harvest opportunities, largely due to the limitation of river navigability for hunters. These findings provide an example in which rapid landscape and resource change may not translate into increased harvest. The integrated assessment with a SES framework revealed new and surprising outcomes, not evident when evaluating social and ecological components separately. This analysis highlighted how a coupled social-ecological framework can be used to assess the effects of climate change on ecosystem services.
    • Community composition and biogeography of beetles and spiders across an elevational gradient in Denali National Park, Alaska

      Haberski, Adam; Sikes, Derek S.; Hollingsworth, Teresa; Armbruster, W. Scott (2020-08)
      Anthropogenic climate change is rapidly altering alpine ecosystems in Alaska. Trees and woody shrubs are expanding upslope and displacing alpine tundra. As alpine tundra habitats shrink and fragment, arthropods and other animals face an increased risk of extirpation due to smaller population sizes and reduced geneflow. Arthropods--insects, spiders, and their relatives--are the most speciose component of the alpine fauna and perform key ecosystem services, such as pollination and nutrient cycling, and are food for vertebrates. Many species have responded by shifting their distribution to higher elevations, but species respond to change idiosyncratically, which could alter species interactions and disrupt communities. I compared beetle and spider communities along an elevational gradient in Denali National Park and Preserve, Alaska, an area with a complex biogeographic history and a poorly known arthropod fauna, in order to 1) examine differences in diversity, abundance, and community composition among forest, shrub, and alpine tundra habitats; 2) link the observed differences to abiotic factors relevant to climate change; and 3) test if shared habitat preferences lead to community-level patterns in geographic distribution. After three consecutive summers of sampling, I found that alpine tundra supports an unexpectedly diverse arthropod community with a high proportion of unique species and that vegetation cover and mean air temperature are strongly correlated with community composition. I therefore expect species losses among alpine tundra communities as shrubification continues. Community-level distribution patterns were not observed, but trends in the data point to a reduction of Holarctic distributions among forest-dwelling arthropods and an increased proportion of Beringian endemics among tundra species. This was the first systematic survey of Denali's terrestrial arthropods and added over 450 new park records.
    • Computational analysis of nanofluids flow and heat transfer in microchannels and fin tube air coils

      Ray, Dustin R.; Das, Debendra K.; Peterson, Rorik A.; Misra, Debasmita; Kim, Sunwoo (2021-05)
      The four goals of this dissertation were to investigate nanofluids' thermal and fluid dynamic performance in (i) an air coil, (ii) microchannel heatsink, using computational fluid dynamic (CFD) software, ANSYS Fluent, develop (iii) hydrodynamic entrance length correlation and (iv) apparent friction factor correlations in rectangular microchannels. In cold regions of the world, ethylene glycol mixed with water (EG/W) are used as a heat transfer fluid instead of water due to their freeze protection. EG/W has low thermal conductivity than water, which can be improved by dispersing nanoparticles and creating a new fluid called nanofluid. A computational scheme was developed based on the Effectiveness-Number of Transfer Unit (ε-NTU) method to compare nanofluids' thermal and fluid dynamic performance to the conventional ethylene glycol and water mixture. The nanofluid's performance was examined by conducting two studies: reducing pumping power and reducing the air coil's surface area via length. The results showed at a dilute concentration of 1% of Al₂O₃ can reduce the pumping power requirements by 35.3% or reduce the air coil length by 7.4% while maintaining the same heat transfer rate as EG/W. The results show nanofluids could provide significant savings in energy or material costs. The nanofluids' (Al₂O₃, CuO, and SiO₂) thermal and fluid dynamic performance used in a microchannel heatsink was explored using analytical and computational methods. The computational model was developed in ANSYS Fluent. Comparing analytical and computational results, good agreement was observed validating both methods. The three nanofluids had a maximum difference of 4.1% for pressure drop and 2.9% for the Nusselt number. Three performance studies were conducted using the analytical model based on constant Reynolds number, maximum surface temperature, and pumping power. A constant Reynolds number of nanofluids could reduce the maximum surface temperature by 6K, but at the cost of increased pumping power. Nanofluids showed the pumping power could be reduced by 23% compared to the base fluid while maintaining equal maximum surface temperature. In electronic cooling applications where microchannel heatsinks are used, nanofluids seem promising for lowering critical components' operating temperatures and contribute to increased life and system reliability. A detailed three-dimensional laminar flow CFD model was developed and ran for Reynolds numbers ranging from 0.1 to 1000 through six rectangular microchannels aspect ratios (α): 1, 0.75, 0.5, 0.25, 0.2, 0.125. The majority of the Reynolds numbers simulated were in the low regime (Re< 100) to fulfill the lack of literature for determining accurate hydrodynamic entrance length and apparent friction factor for microchannels. From these numerical simulations, improved correlations were developed to predict hydrodynamic entrance length with a mean error of less than 2% and a maximum error of 5.75% for 0.1 ≤ Re ≤ 1000 & 0 ≤ α ≤ ∞. For the apparent friction factor in microchannels, three correlations were derived from the numerical simulations: fully developed friction factor (fRe), developing incremental pressure drop number (K(z)), and fully developed incremental pressure drop (K(∞)). The three correlations were used to determine the local fapp,zRe, in the applicable range of 0.1 ≤ Re ≤ 1000 & 0.125 ≤ α ≤ 8. The correlations showed a mean deviation of less than 3% and a maximum deviation of less than 8.3% from the numerical data.
    • Computational and experimental evaluation of nanofluids in heating and cooling forced convection applications

      Strandberg, Roy; Das, Debendra K.; Peterson, Rorik A.; Johnson, Ronald A.; Goering, Douglas J. (2021-05)
      The purpose of the research was to examine the heat transfer and fluid dynamic performance of various nanofluids in heating and cooling applications using empirical and computational methods. Two experiments were performed to characterize and compare the performance of a Al₂O₃/60% ethylene glycol (60% EG) nanofluid to that of its base fluid. In the first experiment, the nanofluid was comprised of Al₂O₃ nanoparticles with 1% volumetric concentration in a 60% ethylene glycol/40% water (60% EG by mass) solution to that of 60%EG in a liquid to air heat exchanger. The test bed used in the experiment was built to simulate a small air handling system typical of that used in heating, ventilating and air conditioning (HVAC) applications. Previously established empirical correlations for thermophysical properties of fluids were used to determine the values of various parameters (e.g. Nusselt number, Reynolds number, and Prandtl number). The testing shows that the 1% Al₂O₃ nanofluid generates a marginally higher heat rate than the 60% EG under certain conditions. At Re=3,000, the nanofluid produced a heat rate that was 2% higher than that of the 60% EG. The empirically determined Nusselt number associated with the convection inside the coil tubing follows the behavior predicted by the Dittus-Boelter correlation quite well (R²=0.97), while the empirically determined Nusselt number for the 60% EG follows the Petukhov correlation similarly well (R²=0.97). Pressure loss and hydraulic power for the nanofluid were higher than for the base fluid over the range of conditions tested. The exergy destroyed in the heat exchange and fluid flow processes were between 8 and 13% higher for the nanofluid over the tested range of Reynolds numbers. The objective of the second study was to experimentally characterize and compare the performance of a nanofluid comprised of Al₂O₃ nanoparticles with 1, 2 and 3% volumetric concentrations in a 60% EG solution to that of 60% EG in a liquid to air heat exchanger. In this experiment, the heating system was operated in a higher temperature regime than in the first experiment. As in the first experiment, the test bed used in the experiment simulated a small air handling system typical of that used in HVAC applications. Entering conditions for the air and liquid were selected to emulate typical operating conditions of commercial air handling systems in sub arctic regions (such as Alaska). In the experiment the nanofluids generally did not perform as well as expected based on previous analytical work. The performance of the 1% nanofluid was generally equal to that of the base fluid considering identical entering conditions. However, the 2% and 3% nanofluids performance was considerably worse than that of the base fluid. The higher concentration nanofluids exhibited heat rates up to 14.6% lower than that of the 60%EG, and up to 44.3% lower heat transfer coefficient. The 1% Al₂O₃/60% EG exhibited 100% higher pressure drop across the coil than the base fluid considering equal heat output. In the computational portion of the research, the performance of a microchannel heat sink (MCHS), similar to those used to cool microprocessors filled with various nanofluids and the corresponding base fluid without nanoparticles are examined. The MCHS is modeled using a three- dimensional conjugate heat transfer and fluid dynamic finite-volume model over a range of conditions. The model incorporates a fixed heat flux of 1,000,000 W/m² at the base of the solid domain. The thermophysical properties of the fluids are based on empirically obtained correlations, and vary with temperature. Nanofluids considered include 60% Ethylene Glycol/40% Water solutions with CuO, SiO₂, and Al₂O₃ nanoparticles dispersed in volumetric concentrations ranging from 1 to 3%. The flow conditions analyzed are in the laminar range (50£Re£300), and consider multiple inlet temperatures. The analyses predict that when compared on an equal Reynolds number basis, the 60%EG/3% CuO nanofluid exhibits the highest heat transfer coefficient, and the largest reduction in average base temperature. At an inlet Reynolds number of 300, and an inlet temperature of 308K the nanofluid is predicted to have an average heat transfer coefficient that is 30% higher than that of the base fluid, while the average temperature on the base of the heat exchanger is 1K lower than that of the base fluid. In contrast, the inlet pressure required for these entering conditions is 192% higher than that for the base fluid, while the required hydraulic power to drive the flow is 366% higher than that of the base fluid. The enhanced heat transfer performance potential of nanofluids comes at the expense of generally higher pumping power consumption.
    • Contextualizing the development of coastal adaptations in postglacial Southeast Alaska

      Schmuck, Nicholas S.; Reuther, Joshua; Clark, Jamie; Baichtal, James F.; Holliday, Vance T.; Plattet, Patrick (2021-05)
      The goal of this dissertation is to improve our understanding of human population expansions into unfamiliar environments, focusing on when and how humans adapted to the rich coastal landscape of Southeast Alaska. Investigation of the peopling of this region has been overshadowed by the broader narrative that the Americas may have been first colonized by a late Pleistocene coastal migration. Refinements to local sea-level and paleoecological chronologies help contextualize the dynamic landscape that these first inhabitants might have encountered, returning focus to the archaeology of Southeast Alaska itself. This research considers existing archaeological data within the theoretical framework of Human Behavioral Ecology, proposing new models to acknowledge the process of landscape learning. Landscape learning provides a mechanism for exploring human adaptation to unfamiliar landscapes, which in turn produces testable hypotheses based on the familiarity of colonizing human foragers with coastal environments. Systematic sourcing of obsidian microblade cores, ubiquitous in early Holocene sites, allows for a further assessment of landscape learning, alongside an evaluation of the relationship between local raw material constraints and technological organization. Though the oldest known archaeological sites in Southeast Alaska are firmly dated to between 10,500 and 10,000 cal BP, older occupations have been identified elsewhere on the Northwest Coast, and Tlingit and Haida oral histories record their presence on the landscape from Time Immemorial. Taken together, multiple lines of evidence point to an initial colonization of Southeast Alaska out of eastern Beringia, occurring prior to the occupation of the oldest known sites. By the early Holocene, foragers with a typical Northwest Coast diet were readily adapting to, but still in the process of learning, this complex coastal landscape. While these results challenge the long-established impression that the oldest known sites in the region represent a remnant population of maritime sea-mammal hunters descended from an earlier coastal migration into the Americas, this research highlights the opportunity to continue testing these hypotheses by targeting older, uplifted paleoshorelines.
    • Control of internal transport barriers in magnetically confined tokamak fusion plasmas

      Panta, Soma Raj; Newman, David; Wackerbauer, Renate; Ng, Chung Sang; Sanchez, Raul (2020-07)
      In the Tokamak plasma, for fusion to be possible, we have to maintain a very high temperature and density at the core at the same time keeping them low at the edge to protect the machine. Nature does not favor gradients. Gradients are source of free energy that causes instability. But we require a large gradient to get energy from plasma fusion. We therefore, apply a huge magnetic field on the order of few Tesla (1 T-10 T) that confines the plasma in the core, maintaining gradients. Due to gradients in density of charged particles (ions and electrons), there is an electric field in the plasma. Heat and particle transport takes place from core to edge mainly through anomalous transport while the E x B velocity sheer acts to reduce the transport of heat and particles. The regime at which the E x B velocity shear exceeds the maximum linear instability growth rate, as a result, the transport of particles and heat gets locally reduced is termed as the formation of a transport barrier. This regime can be identified by calculating the transport coefficients in the local region. Sometimes it can be observed in the edge where it is called an edge barrier while if it is near the core it is an internal transport barrier. There is a positive feedback loop between gradients and transport barrier formation. External heating and current drives play an important role to control such barriers. Auxiliary heating like neutral beam injection (NBI) and radio frequency (RF) heating can be used at a proper location (near the core of the plasma) to trigger or (far outside from the core) to destroy those barriers. Barrier control mechanism in the burning plasmas in international thermonuclear test reactor (ITER) parameter scenarios employing fusion power along with auxiliary heating source and pellets are studied. Continuous bombardment with pellets in the interval of a fraction of a second near the core of the burning plasma results in a stronger barrier. Frozen pellets along with auxiliary heating are found to be helpful to control the barriers in the tokamak plasmas. Active control mechanism for transport barriers using pellets and auxiliary heating in one of tokamaks in United States (DIII-D) parameter scenarios are presented in which intrinsic hysteresis is used as a novel control tool. During this process, a small background NBI power near the core assists in maintaining the profile. Finally, a self-sustained control mechanism in the presence of core heating is also explored in Japanese tokamak (JT-60SA) parameter scenarios. Centrally peaked narrow NBI power is mainly absorbed by ions with a smaller fraction by the electrons. Heat exchange between the electron and ion channels and heat conduction in the electron channel are found to be the main processes that govern this self control effect. A strong barrier which is formed in the ion channel is found to play the main role during the profile steepening while the burst after the peaked core density is found to have key role in the profile relaxation.
    • Cultural adaptations of evidence based practices in supporting children diagnosed with autism spectrum disorder

      James, Krista P.; Barnhardt, Raymond; Leonard, Beth; Wells, Cassie; Healy, Joanne (2020-08)
      Research shows that early identification and intervention result in a higher quality of life and contribution to society for individuals with Autism Spectrum Disorder (ASD). As society sees an ever-increasing percentage of individuals diagnosed with ASD, identification of culturally responsive, evidence-based practices is of critical importance. While the National Autism Center has provided a guide to evidence-based practices, minimal research has been done to determine if these practices are culturally relevant. This is a community-based formative research project. The purpose of this project was to evaluate the cultural appropriateness of the practices identified as "evidence-based practices" by the National Autism Center in the 2015 standards report, specifically a token economy system which is a positive behavioral support that utilizes the principles of applied behavior analysis to decrease challenging behaviors and increase positive behaviors. The study utilized qualitative research strategies, including surveys and interviews within the American Samoan community, to accomplish this evaluation. The surveys and interviews were analyzed using coding principles to generate themes. The researcher was contacted by the American Samoan Department of Education to provide training for educators and parents on utilizing evidence-based practices to support children with autism. The results of this study inform the content of the ongoing training efforts.
    • Design, manufacture, and testing of a modular array for three-dimensional photovoltaics

      Fiscus, Trevar; Peterson, Rorik; Huang, Daisy; Denkenberger, David (2020-08)
      The emerging technology of three-dimensional photovoltaics is explored, shedding light on past research, current developments, and recommendations for future work. Research was performed at the University of Alaska Fairbanks analyzing six different geometric configurations of solar cells, both computationally and experimentally. The primary work described in this paper is the design and production of a modular solar array prototype and the experimental setup used to test the power output of the different configurations. Data collected from hundreds of tests were processed and analyzed to find optimum configuration angles and recommendations for future research. Working through the process of designing and manufacturing the equipment, and then subsequently using it for experimentation, provided many insights into recommended improvements. This text is organized into eight chapters that detail the background of research in using three-dimensional space for solar power generation, the recent project completed at the University of Alaska Fairbanks, and the proposed guidance for future work on this topic. This paper and use of the sources cited herein should provide the reader with the background and tools necessary to continue research. The latter chapters should act as a guide for the future design of components to be used in laboratory experimentation. It is hoped that this report, the collected data, and associated files from this project will add to the knowledge base of threedimensional solar arrays and help advance the technology one step closer to real-world application.
    • The development and initial testing of the vertical comet assay, a novel technique for the study of DNA damage and repair

      Williams, Robert T. D.; Pdlutsky, Andrej; Chen, Cheng-fu; Drew, Kelly (2021-05)
      Gene-specific repair is the idea that certain segments of the genome repair at a faster rate than others. This idea, if demonstrated with adequate evidence, would have large implications for the field of biology as a whole, with special significance for the fields of oncology, gerontology, and molecular and cell biology. The concept of gene-specific repair is not new, with the earliest references in the literature dating back to 1985, and there is a small volume of evidence derived over the years. However, the evidence generated so far is not enough to conclusively prove the existence of gene-specific DNA repair. Generally, the reason for the lack of evidence is that currently available assays and techniques are not adequate for the study of gene-specific repair on a large scale as the techniques that are available require a great deal of time, funding, and skill to generate a reliable and conclusive data set for a single gene, let alone the entire genome. The vertical comet technique described here-in is a response to the perceived need for a robust and relatively high-throughput technique for the study of gene-specific DNA repair. In the traditional comet assay, cells are fixed in agarose gel. Electrophoresis is performed, following several treatment steps, to create a ball of nuclear material embedded in the agarose gel with a 'tail' of smaller pieces of nominally damaged DNA extending to one side. The vertical comet captures this tail DNA in a buffer, allowing for its further analysis with processes such as quantification, PCR/qPCR, and sequencing. The capture of the tail DNA not only makes genespecific repair studies possible, it also allows the vertical comet to fulfill the role of the traditional comet assay with a number of advantages - a reduction in human bias, a reduction in labor-hours required for work, and a reduction in inter-lab variability of results.
    • Development of a vertical oscillator energy harvester: design and testing of a novel renewable resource power conversion system

      Wise, Michael A. Jr.; Al-Badri, Maher; Wies, Richard Jr.; Kasper, Jeremy (2020-12)
      Remote Alaska communities have historically dealt with elevated electric power expenses due to high cost of transporting diesel fuel for power generation. To offset this cost, the installation of various renewable resources have been utilized, particularly wind and solar power. Hydrokinetic generation by harnessing river flows is an emerging and less commonly implemented renewable resource that offers great potential for power generation. Specifically, this study investigates the behavior of a novel concept for harnessing vertical oscillation that occurs when a bluff body is inserted into a flow path. Unlike traditional rotating turbines used in hydrokinetic energy, this particular device utilizes the fluid structure interactions of vortex-induced-vibration and gallop. Due to the unique characteristics of this vertical motion, a thorough examination of the proposed system was conducted via a three-pronged approach of simulation, emulation, and field testing. Using a permanent magnet synchronous generator as the electrical power generator, an electrical power conversion system was simulated, emulated, and tested to achieve appropriate power smoothing for use in microgrid systems present in many Alaskan rural locations.
    • Development of scalable energy distribution models to evaluate the impacts of renewable energy on food, energy, and water system infrastructures in remote Arctic microgrids of Alaska

      Karenzi, Justus; Wies, Richard; Huang, Daisy; Al-Badri, Maher (2020-08)
      Experience and observations from remote Alaska communities have shown that energy is inarguably at the center of food, energy, and water (FEW) security. The availability of potable water, fresh produce, food storage, or processed seafood ultimately depends on a reliable and adequate energy supply. For most communities, diesel fuel is the primary source of power, which comes at high cost because of the logistics associated with importing the fuel to these relatively isolated communities. Integrating locally available renewable energy resources not only enhances energy supply, but the impacts further translate to food and water security in remote microgrids. The focus of this work is to investigate how intermittent renewable energy sources impact community level food and water infrastructure systems in a remote Arctic microgrid. Energy distribution models are mathematically developed in MATLAB® Simulink® to identify, describe, and evaluate the connections between intermittent renewable resources and the FEW loads. Energy requirements of public water systems, greenhouses, cold storage units, seafood processing loads, and modular water and food system loads are evaluated. Then energy sources including solar PV, solar thermal collectors, wind, hydro, energy storage, and diesel electric generation are modeled and validated. Finally, simulations of scenarios using distributed energy resources to serve water and food infrastructure loads are carried out including the incorporation of dispatchable loads. The results indicate that the impacts of renewable energy on FEW infrastructure systems are highly seasonal, primarily because of the variability of renewable resources. The outcome of this work helps in gaining firsthand insights into FEW system dynamics in a remote islanded microgrid setting.
    • Development of working fluid control techniques for improved ramping response in geothermal-based organic Rankine cycle generation systems

      Shofowora, Abayomi John; Wies, Richard; Denkenberger, David; Al-Badri, Maher (2021-05)
      Small-scale low-temperature geothermal-based electricity generation systems are under development for use as grid supporting and grid forming power sources in remote locations. Conversion of low-temperature heat to electrical energy in an organic Rankine cycle using working fluids such as refrigerants is challenging due to the low energy conversion efficiency of the process and the significantly slower thermal response rate in comparison to the time response of the electrical grid for changes in electrical generation and load. There is a need to investigate techniques for controlling the flow of the working fluid in combination with the use of a secondary heat exchanger to improve ramping response of these systems. This research project develops and models a working fluid control technique that incorporates power electronic technologies that could help to improve the ramping response of geothermal-based organic Rankine cycle generation systems. The performance of the model is examined with the aid of simulations in MATLAB® Simulink®. The results from these simulations are used to develop a functional and reliable control technique for ramping response improvement in geothermal-based electricity generation systems using organic Rankine cycles.
    • The effect of Siberian alder on the activities of three extracellular enzymes and their implications for soil decomposition in Arctic and boreal Alaska

      Heslop, Calvin; Ruess, Roger; Bret-Harte, Syndonia; Kielland, Knut (2020-08)
      As tall shrubs increase in extent and abundance in response to a changing climate, they have the potential to substantially alter ecosystem nutrient availability and carbon (C) balance. Siberian alder (Alnus viridis ssp. fruticosa), a nitrogen (N) fixing shrub, is among the species responding to climate warming in both the Arctic and boreal forests. Alder-fixed N has the potential to increase decomposition of labile C, by relieving N limitation on microbial activity. Simultaneously, it has the potential to decrease decomposition of recalcitrant C by downregulating microbial N mining. The net effect of N additions is influenced by the relative quality of the soil C and could determine whether alder N additions result in a net sink or source of C to the atmosphere. We measured the activities of three extracellular enzymes in bulk organic soils under and away from alder canopies, in stands differing in soil organic matter quality, in both arctic and boreal forest regions of Alaska, USA. In the Alaskan arctic, the proximity of alder increased the activities of both recalcitrant and labile C-degrading enzymes regardless of soil C quality, potentially resulting in increased C losses. In the boreal forest, enzyme activities did not differ with alder proximity nor stand soil C quality, possibly due to long legacies of alder N inputs relieving microbial N limitation in these stands. As arctic and boreal forest ecosystems experience shifts in the distribution and abundance of this N fixing shrub, alders' influence on soil decomposition could have significant consequences for high latitude soil C budgets.
    • Effectiveness, environmental pathways and operational readiness of OP-40 chemical herder when used in conjunction with in-situ burning for oil spill reponse in the offshore Arctic

      Bullock, Robin J.; Perkins, Robert A.; Aggarwal, Srijan; Schnabel, William; Barnes, David; Allen, Alan (2021-05)
      The Arctic is the northern most part of the Earth, and within Alaska (United States), is home to approximately 10,000 people, the majority of which are indigenous populations. It contains some of the largest reserves of natural resources and the most extensive and continuous wilderness areas in the world. As the Earth's climate changes, so does the Arctic and its economy, its commercial opportunities as well as the associated risks. One such risk is the unintentional release of oil into the offshore Arctic environment from resource extraction, commercial fishing, tourism or marine shipping. Oil spills in this environment prove damaging to the marine population, as well as logistically challenging given the remote landscape, harsh temperatures, ice cover and difficult working conditions. The primary oil spill response methods are mechanical recovery, chemical dispersion, and/or in-situ burning. Regarding possible spills in Arctic seawaters, the choice of response option depends on ice cover, along with other factors. In-situ burning is a possible primary response option if the oil slick is thick enough to sustain burning and may be one of the few options available for use in ice-covered waters. Chemical agents, known as thickening agents or "herders", may enhance the opportunities for in-situ burning by temporarily thickening of the oil slick in order to sustain a burn. With careful evaluation of the physical and chemical processes involved with herder application and subsequent burning and their ultimate fate within the environment; industry, government, Alaska native and other interested parties would be better able to assess the usefulness of this response option and judge the safety and effectiveness of herder use in the Arctic, as well as estimate its effects on the environment.