ScholarWorks@UA

ScholarWorks@UA is University of Alaska's institutional repository created to share research and works by UA faculty, students, and staff.

 

 

  • Domestic Violence Primary Prevention: Evidence from the Past Decade

    Johnson, Ingrid (Alaska Justice Information Center, 2024-07-12)
    This fact sheet summarizes findings from 16 meta-analyses synthesizing the results of evaluations of primary domestic violence prevention interventions between 2014 and 2024. Primary prevention includes policies or programs that stop the onset of crime perpetration and/or victimization. Domestic violence includes sexual violence, stalking, physical violence, psychological aggression, and/or control of reproductive or sexual health by spouses, boy or girlfriends, dating partners, or hook up partners. Findings show a preventative effect amongst youth and community-based adults, while no preventative effect was seen in college students.
  • The avialan fauna of the late Cretaceous Prince Creek Formation, Alaska

    Wilson, Lauren N.; Druckenmiller, Patrick; Fowell, Sarah; Ksepka, Daniel (2024-05)
    Modern polar regions are critical breeding grounds for over 250 species of birds. Some migrate to high latitudes for access to seasonally abundant resources during reproductive periods, whereas others are year-round residents. Despite the major role these birds play in polar ecosystems, we know very little of the origins of the utilization of polar ecosystems for nesting due to the rarity of avialan fossils from high latitudes. The avialan fossil record spans 150 million years, yet evidence for high-latitude bird reproduction extends only to the Eocene La Meseta Formation of Antarctica (56-33.6 Ma). Here, we report a remarkable polar avifauna from the northernmost fossil-bearing Late Cretaceous ecosystem in the world, the Prince Creek Formation of northern Alaska (PCF). The PCF was deposited at 80-85°N paleolatitude, where continuous summer daylight would have lasted nearly six months. It preserves an ancient polar ecosystem including avian and non-avian dinosaurs, mammals, and fishes. The PCF avialan material was found as part of a decade-long microfossil analysis of channel lag deposits. Numerous skeletal elements, representing almost the entire avialan skeleton, constitute one of the most comprehensive and well-preserved Late Cretaceous avifaunas in the world. These fossils share morphological affinities with hesperornithines, ichthyornithines, and crown birds. Further, abundant perinatal fossils represent the youngest-known growth stages of Mesozoic euornithines. This is the oldest direct evidence for polar bird reproduction and demonstrates that multi ---taxic bird nesting has occurred in the High Arctic for at least 73 million years--nearly half the tenure for birds on Earth. Likewise, these fossils demonstrate that this behavior originated in the Mesozoic ancestors of modern birds, millions of years before the radiation of crown group birds following the end-Cretaceous mass extinction.
  • Effects of hunting pressure on the spatial dynamics of a subarctic caribou herd

    Wells, Jeffrey; Crimmins, Shawn; Brinkman, Todd; Bentzen, Torsten (2024-05)
    Indirect effects of hunting can have important ecological and hunt management implications, and little has been done to quantify these indirect effects on caribou (Rangifer tarandus). To assess effects of hunting pressure on caribou spatial dynamics, we used GPS locations that spanned fall and winter 2010-2022 from the semi-migratory Fortymile caribou herd in interior Alaska. We analyzed these locations using integrated step selection analysis to evaluate step lengths (i.e., movement rates) and selection of distance to roads and trails, and forest cover across 3 hunting pressure levels (none, low, and high) as well as road crossings during hunting compared to non-hunting periods. We found that the caribou response to hunting pressure varied by season and, within the fall season, by hunting pressure level. Relative to no hunting pressure, caribou in fall showed a very strong avoidance of roads at high hunting pressure and a lower avoidance at low hunting pressure. Similarly, caribou in fall showed an avoidance of trails at high hunting pressure although, unlike roads, the avoidance continued at low hunting pressure. Conversely, relative to no hunting pressure, caribou did not change their selection of forest cover in either season nor did they alter their selection of roads or trails in winter. Furthermore, in both seasons, changes in step lengths in response to hunting pressure were less than we expected. Last, caribou avoided road crossings more during hunting compared to non-hunting periods in both seasons. Overall, caribou response to hunting pressure could have implications for caribou availability to hunters, especially during the fall season, as well as caribou distribution in relation to roads across both seasons. Hunt managers and public stakeholders could use our results to inform how changes to caribou harvest management might indirectly impact caribou movements and hunter opportunity.
  • Early life biology and ecology of king and tanner crabs in the Bering and Chukchi seas

    Weems, Jared; Eckert, Ginny; Mueter, Franz; Kimmel, David; Long, W. Christopher (2024-05)
    Pelagic larvae and early benthic juveniles are believed to be the most vulnerable life stages for crabs. Where and when young crab occur and their response to environmental conditions is poorly understood. I present two case studies that demonstrate the importance of monitoring crab early life stages of economically and ecologically important species in the Bering and Chukchi Seas. First, collapsed fisheries and poor juvenile recruitment are recurring issues for many Alaska king crab stocks. Among the most notable examples, Pribilof Islands blue king crab is a federally overfished stock that has failed to rebuild after decades of conservation. Comparison of field assessments from modern and historical periods suggests a current bottleneck in larval supply, severely limiting blue king crab recruitment. Supplementary assessments showed available nursery habitats and fish predation pressure do not appear to be limiting for juvenile king crabs. Blue king crab are unlikely to recover by natural means, therefore juvenile enhancement may be an appropriate tool for possible restoration. Second, larval crab dispersal during the pelagic life phase is relatively unknown across the Pacific Arctic. A multiyear study of larval crab abundance and distribution during late summer months, and their association with environmental covariates, was completed for the north Bering and Chukchi Seas. Larval community structure varied strongly across regions from south to north and many species and stages had specific associations with coastal or offshore water masses. Snow crab larvae were relatively abundant and ubiquitous across the study region and appear to originate from both Pacific and Arctic spawning stocks. Blue king crab larvae were relatively rare in the Chukchi Sea and likely dispersed away from north Bering Sea natal areas. Larvae likely experience increased growth rates and northward dispersal in warm years, which could impact delivery to and survival of settling crabs in nursery habitats. Across analyses, these results improve our understanding of early life dispersal, settlement processes, and possible recruitment bottlenecks for Arctic crab stocks.
  • Synthesis and stereoselective reduction of α-fluoro-β-ketoesters by ketoreductases

    Vanagel, Matthew G.; Green, Tom; Rasley, Brian; Kuhn, Thomas (2024-05)
    Using commercially available ketoreductase (KRED) enzymes, α-fluoro-β-hydroxy esters were stereoselectively synthesized from racemic α-fluoro-β-keto esters through dynamic reductive kinetic resolution (DYRKR). The α-fluoro-β-keto esters were synthesized via Reformatsky reactions between an aromatic aldehyde and ethyl bromofluoroacetate and subsequent oxidation with Dess Martin Periodinane (DMP). Two enzymes were selected for their ability to yield either syn or anti diastereomers. Three aromatic substrates were reduced in high diastereomeric and enantiomeric excess and good yields. The KRED products were derivatized with (R)- and (S)-α-methoxy-α-trifluoromethylphenylacetic acid (MTPA) and analyzed via ¹⁹F NMR spectroscopy to determine their absolute stereochemistry via Mosher ester analysis. For the three substrates, KRED 110 yielded the anti 2S,3S isomer. KRED 130 predominantly yielded the syn 2S,3R isomer but with less specificity. The use of these commercially available KRED enzymes provides access to enantio- and diastereomerically pure α-fluoro-β-hydroxy esters from readily accessible racemic substrates. Optically pure α-fluoro-β-hydroxy esters may serve as useful intermediates in the synthesis of medicinally relevant compounds such as fluorinated amino acids or fluorinated sphingolipid derivatives.

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