• Tidal Echoes 2014

      Stangeland, Meghan; Salsman, Rebecca; Unzicker, Guy; Wall, Emily; Maier, Kevin; Landis, Rod; Neely, Sol; Minton, Sara; Enge, Carrie; Wedler, Annie; et al. (University of Alaska Southeast, 2014-03-20)
      Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2015

      Salsman, Rebecca; Cherry, Alexa; Wall, Emily; Neely, Sol; Wade, John; Elliot, William; Dewees, Andrea; Trafton, Math; Landis, Rod; Huff, Ben; et al. (University of Alaska Southeast, 2015-03-20)
      The 2015 edition of Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2016

      Cherry, Alexa; Clark, Maranda; Wall, Emily; Maier, Kevin; Neely, Sol; Enge, Carrie; Elliot, William; Hayes, Ernestine; Trafton, Math; Alexander, Rosemarie; et al. (University of Alaska Southeast, 2016-03-20)
      The 2016 edition of Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2017

      Clark, Maranda; Rumfelt, Elizabeth; Wall, Emily; Lamb, Jonas; Elliot, William; Trafton, Math; Hayes, Ernestine; Chordas, Nina; Martin, Mary Catherine; Enge, Carrie; et al. (University of Alaska Southeast, 2017)
      The 2017 edition of Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2018

      Rumfelt, Elizabeth; Busby, India; Wall, Emily; Lamb, Jonas; Elliot, William; Trafton, Math; Martin, Mary Catherine; Young, Karragh; Kane, Jeremy; Zacher, Liz; et al. (University of Alaska Southeast, 2018)
      Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2019

      Busby, India; Ziegler, Callie; Wall, Emily; Lamb, Jonas; Elliot, William; Bannerman, Amy; Trafton, Math; Landis, Rod; Alexander, Rosemarie; Neeland, Allison; et al. (University of Alaska Southeast, 2019)
      Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2020

      Ziegler, Callie; Bergren, Erika; Wall, Emily; Elliot, William; Bannerman, Amy; Trafton, Math; Alexander, Rosemarie; Maier, Kevin; Kane, Jeremy; Zacher, Liz (University of Alaska Southeast, 2020)
      Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidal Echoes 2021

      Alexander, Rosemarie; Bannerman, Amy; Bergren, Erika; Bowman, Emily; Elliot, William; Florian, Steve; Goodman, Jessy; Kane, Jeremy; Kirsch, Geoff; Lamb, Jonas; et al. (University of Alaska Southeast, 2021)
      Tidal Echoes presents an annual showcase of writers and artists who share one thing in common: a life surrounded by the rainforests and waterways of Southeast Alaska.
    • Tidewater glacier response to individual calving events

      Amundson, Jason M.; Truffer, Martin; Zwinger, Thomas (Cambridge University Press, 2022-03-15)
      Tidewater glaciers have been observed to experience instantaneous, stepwise increases in velocity during iceberg-calving events due to a loss of resistive stresses. These changes in stress can potentially impact tidewater glacier stability by promoting additional calving and affecting the viscous delivery of ice to the terminus. Using flow models and perturbation theory, we demonstrate that calving events and subsequent terminus readvance produce quasi-periodic, sawtooth oscillations in stress that originate at the terminus and propagate upstream. The stress perturbations travel at speeds much greater than the glacier velocities and, for laterally resisted glaciers, rapidly decay within a few ice thickness of the terminus. Consequently, because terminus fluctuations due to individual calving events tend to be much higher frequency than climate variations, individual calving events have little direct impact on the viscous delivery of ice to the terminus. This suggests that the primary mechanism by which calving events can trigger instability is by causing fluctuations in stress that weaken the ice and lead to additional calving and sustained terminus retreat. Our results further demonstrate a stronger response to calving events in simulations that include the full stress tensor, highlighting the importance of accounting for higher order stresses when developing calving parameterizations.
    • Time-dependent basal stress conditions beneath Black Rapids Glacier, Alaska, USA, inferred from measurements of ice deformation and surface motion

      Amundson, Jason M.; Truffer, Martin; Luthi, Martin P. (International Glaciological Society, 2006-06-23)
      Observations of surface motion and ice deformation from 2002–03 were used to infer mean stress fields in a cross-section of Black Rapids Glacier, Alaska, USA, over seasonal timescales. Basal shear stresses in a well-defined zone north of the center line (orographic left) were approximately 7% and 16% lower in spring and summer, respectively, than in winter. Correspondingly higher stresses were found near the margins. These changes in the basal shear stress distribution were sufficiently large to cause mean surface velocities to be 1.2 and 1.5 times larger in spring and summer than in winter. These results were inferred with a simple inverse finite-element flow model that can successfully reproduce bulk surface velocities and tiltmeter data. Stress redistribution between the well-defined zone and the margins may also occur over much shorter time periods as a result of rapidly changing basal conditions (ice–bed decoupling or enhanced till deformation), thereby causing large variations in surface velocity and strongly influencing the glacier’s net motion during summer.
    • Toward Understanding Bacterial Ice Nucleation

      Lukas, Max; Schwidetzky, Ralph; Eufemio, Rosemary J.; Bonn, Mischa; Meister, Konrad (American Chemical Society, 2022-01-27)
      Bacterial ice nucleators (INs) are among the most effective ice nucleators known and are relevant for freezing processes in agriculture, the atmosphere, and the biosphere. Their ability to facilitate ice formation is due to specialized ice-nucleating proteins (INPs) anchored to the outer bacterial cell membrane, enabling the crystallization of water at temperatures up to −2 °C. In this Perspective, we highlight the importance of functional aggregation of INPs for the exceptionally high ice nucleation activity of bacterial ice nucleators. We emphasize that the bacterial cell membrane, as well as environmental conditions, is crucial for a precise functional INP aggregation. Interdisciplinary approaches combining high-throughput droplet freezing assays with advanced physicochemical tools and protein biochemistry are needed to link changes in protein structure or protein–water interactions with changes on the functional level.
    • Tracking icebergs with time-lapse photography and sparse optical flow, LeConte Bay, Alaska, 2016–2017

      Kienholtz, Christian; Amundson, Jason M.; Motyka, Roman J.; Jackson, Rebecca H.; Mickett, John B.; Sutherland, David A.; Nash, Jonathan D.; Winters, Dylan S.; Dryer, William P.; Truffer, Martin (International Glaciological Society, 2019-03-07)
      We present a workflow to track icebergs in proglacial fjords using oblique time-lapse photos and the Lucas-Kanade optical flow algorithm. We employ the workflow at LeConte Bay, Alaska, where we ran five time-lapse cameras between April 2016 and September 2017, capturing more than 400 000 photos at frame rates of 0.5–4.0 min−1 . Hourly to daily average velocity fields in map coordinates illustrate dynamic currents in the bay, with dominant downfjord velocities (exceeding 0.5 m s−1 intermittently) and several eddies. Comparisons with simultaneous Acoustic Doppler Current Profiler (ADCP) measurements yield best agreement for the uppermost ADCP levels (∼ 12 m and above), in line with prevalent small icebergs that trace near-surface currents. Tracking results from multiple cameras compare favorably, although cameras with lower frame rates (0.5 min−1 ) tend to underestimate high flow speeds. Tests to determine requisite temporal and spatial image resolution confirm the importance of high image frame rates, while spatial resolution is of secondary importance. Application of our procedure to other fjords will be successful if iceberg concentrations are high enough and if the camera frame rates are sufficiently rapid (at least 1 min−1 for conditions similar to LeConte Bay).
    • Tracking icebergs with time-lapse photography and sparse optical flow, LeConte Bay, Alaska, 2016–2017

      Kienholz, Christian; Amundson, Jason M.; Motyka, Roman J.; Jackson, Rebecca H.; Mickett, John B.; Sutherland, David A.; Nash, Jonathan D.; Winters, Dylan S.; Dryer, William P.; Truffer, Martin (Journal of Glaciology, 2019-03-07)
      We present a workflow to track icebergs in proglacial fjords using oblique time-lapse photos and the Lucas-Kanade optical flow algorithm. We employ the workflow at LeConte Bay, Alaska, where we ran five time-lapse cameras between April 2016 and September 2017, capturing more than 400 000 photos at frame rates of 0.5–4.0 min−1. Hourly to daily average velocity fields in map coordinates illustrate dynamic currents in the bay, with dominant downfjord velocities (exceeding 0.5 m s−1 intermittently) and several eddies. Comparisons with simultaneous Acoustic Doppler Current Profiler (ADCP) measurements yield best agreement for the uppermost ADCP levels (∼ 12 m and above), in line with prevalent small icebergs that trace near-surface currents. Tracking results from multiple cameras compare favorably, although cameras with lower frame rates (0.5 min−1) tend to underestimate high flow speeds. Tests to determine requisite temporal and spatial image resolution confirm the importance of high image frame rates, while spatial resolution is of secondary importance. Application of our procedure to other fjords will be successful if iceberg concentrations are high enough and if the camera frame rates are sufficiently rapid (at least 1 min−1 for conditions similar to LeConte Bay).
    • Transition in Rural Communities: Opportunities for Secondary Students with Disabilities. A Meta-Synthesis

      Anderson, Nancy (University of Alaska Southeast, 2012-06-11)
      This metasynthesis examines transition planning and services in rural communities, especially those in Alaska. It considers the barriers and challenges to transition implementation, the cultural responsiveness of rural educators, the developments in and suggestions for transition services, and approaches and strategies for transition planning. It illuminates the importance of building community relationships and tapping into human resources. Finally, the metasynthesis stresses the rural educator's need for cultural sensitivity in rural Alaska Native communities.
    • Transition Planning for Secondary Students with Learning Disabilities: A Meta-Synthesis

      McKim, Howard (University of Alaska Southeast, 2012-06-11)
      Despite increasing legal requirements in planning and documentation, transition outcomes for secondary LD students continue to fall short of pre-graduation expectations. As students move from the supportive and controlled environment of public school education systems to the less structured world of work or post-secondary education, a myriad of skills, supports, and coordinated efforts are needed for optimal outcomes. As the number of students qualifying for services continues to rise, analysis of the shortcomings and successes of the current special education transition strategies is becoming increasingly important. This meta-synthesis of the literature on transitioning secondary LD students investigates the realities of secondary transition planning and the difficulties in implementation.
    • Trauma-Informed Practices

      Hercha, Anna (University of Alaska Southeast, 2019)
      This meta-synthesis of the literature on K-8 teachers with disabilities examines the profound influence that teachers can have on students dealing with trauma in their lives. Teachers can add to the students’ frustration and pain or, with understanding and specific techniques, teachers can help students to process the traumatic situations in their lives and advocate for the student in a way that will help retain trust in other people. In this meta-synthesis, these techniques will be examined and discussed through the lens of preparing to work with traumatized students who fall under differing special education categories.
    • TRICHOTILLOMANIA: EDUCATIONAL ISSUES

      Thomas Scott Duke, Jill Burkert, Jennifer Ward; Voth, David (2009)
      Twenty journal articles that examined the condition trichotillomania that are included in national journal databases created for educators were reviewed by a special education teacher. The articles were classified by publication type (e.g., empirical studies, descriptive articles, guides). Fourteen of the 20 articles were empirical studies. The studies were classified by research design (quantitative or mixed methods), the participants and data sources were identified, and the findings were summarized. The author analyzed the 20 articles utilizing a modified version of the Stevick-Collaizi-Keen method to develop themes that represent the essence of the literature. The four themes that emerged from the analysis include: (a) trichotillomania demographics; (b) social behaviors associated with trichotillomania; (c) trichotillomania and the school experience; and (d) trichotillomania treatments. The themes were connected to the role of the author as a special education teacher. Finally, the author reflected upon the changes the understanding illuminated by the analysis of the literature will have on his career
    • Trophic Transfer of Macroalgal Fatty Acids in Two Urchin Species: Digestion, Egestion, and Tissue Building

      Schram, Julie B.; Kobelt, Julia N.; Dethier, Megan N.; Galloway, Aaron W. E. (Frontiers in Ecology and Evolution, 2018-06-19)
      Sea urchins are ecosystem engineers of nearshore benthic communities because of their influence on the abundance and distribution of macroalgal species. Urchins are notoriously inefficient in assimilation of their macroalgal diets, so their fecal production can provide a nutritional subsidy to benthic consumers that cannot capture and handle large macroalgae. We studied the assimilation of macroalgal diets by urchins by analyzing the profiles of trophic biomarkers such as fatty acids (FAs). We tracked macroalgal diet assimilation in both Strongylocentrotus droebachiensis and S. purpuratus. Juvenile S. droebachiensis and adult S. purpuratus were maintained for 180 and 70 days, respectively, on one of three monoculture diets from three algal phyla: Nereocystis luetkeana, Pyropia sp., or Ulva sp. We then analyzed FA profiles of the macroalgal tissue fed to urchins as well as urchin gonad, gut, digesta, and egesta (feces) to directly evaluate trophic modification and compare nutritional quality of urchin food sources, urchin tissues, and fecal subsidies. In the S. purpuratus assay, there were significantly more total lipids in the digesta and egesta than in the algae consumed. The FA profiles of urchin tissues differed among urchin species, all diets, and tissue types. Despite these differences, we observed similar patterns in the relationships between the urchin and macroalgal tissues for both species. Egesta produced by urchins fed each of the three diets were depleted with respect to the concentration of important long chain polyunsaturated fatty acids (LCPUFAs), but did not differ significantly from the source alga consumed. Both urchin species were shown to synthesize and selectively retain both the precursor and resulting LCPUFAs involved in the synthesis of the LCPUFAs 20:4ω6 and 20:5ω3. S. droebachiensis and S. purpuratus exhibited consistent patterns in the respective depletion and retention of precursor FAs and resulting LCPUFAs of Pyropia and Ulva tissues, suggesting species level control of macroalgal digestion or differential tissue processing by gut microbiota. For both S. droebachiensis and S. purpuratus, macroalgal diet was a surprisingly strong driver of urchin tissue fatty acids; this indicates the potential of fatty acids for future quantitative trophic estimates of urchin assimilation of algal phyla in natural settings.
    • U.A. Journal 1983-02-23 (v.2 no.7)

      University of Alaska, Juneau, 1983-02-23
    • U.A. Journal 1983-03-09 (v.2 no.8)

      University of Alaska, Juneau, 1983-03-09