Viser treff 781-800 av 1637

    • Reduced immune responsiveness contributes to winter energy conservation in an Arctic bird 

      Nord, Andreas; Arne, Hegemann; Folkow, Lars (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-27)
      Animals in seasonal environments must prudently manage energy expenditure to survive the winter. This may be achieved through reductions in the allocation of energy for various purposes (e.g. thermoregulation, locomotion, etc.). We studied whether such trade-offs also include suppression of the innate immune response, by subjecting captive male Svalbard ptarmigan (<i>Lagopus muta hyperborea</i>) to ...
    • The neglected season: Warmer autumns counteract harsher winters and promote population growth in Arctic reindeer 

      Loe, Leif Egil; Liston, Glen E.; Pigeon, Gabriel; Barker, Kristin; Horvitz, Nir; Stien, Audun; Forchhammer, Mads C.; Getz, Wayne M.; Irvine, Robert Justin; Lee, Aline Magdalena; Movik, Lars K.; Mysterud, Atle; Pedersen, Åshild Ønvik; Reinking, Adele K.; Ropstad, Erik; Trondrud, Liv Monica; Tveraa, Torkild; Veiberg, Vebjørn; Hansen, Brage Bremset; Albon, Steve D. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-24)
      Arctic ungulates are experiencing the most rapid climate warming on Earth. While concerns have been raised that more frequent icing events may cause die‐offs, and earlier springs may generate a trophic mismatch in phenology, the effects of warming autumns have been largely neglected. We used 25 years of individual‐based data from a growing population of wild Svalbard reindeer, to test how warmer ...
    • Circadian clock mechanism driving mammalian photoperiodism 

      Wood, Shona Hiedi; Hindle, Matthew; Mizoro, Yasutaka; Cheng, Y; Saer, Ben; Miedzinska, K; Christian, Helen; Begley, Nicola; McNeilly, Judy; McNeilly, Alan; Meddle, Simone; Burt, Dave; Loudon, Andrew S.I. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-27)
      The annual photoperiod cycle provides the critical environmental cue synchronizing rhythms of life in seasonal habitats. In 1936, Bünning proposed a circadian-based coincidence timer for photoperiodic synchronization in plants. Formal studies support the universality of this so-called coincidence timer, but we lack understanding of the mechanisms involved. Here we show in mammals that long photoperiods ...
    • Meiofauna as a valuable bioindicator of climate change in the polar regions 

      Leasi, Francesca; Sevigny, Joseph L.; Hassett, Brandon (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-14)
      Establishing robust estimates of polar marine biodiversity is important for interpreting future changes in the Arctic; however, despite a recent increase in scientific expeditions, this region remains relatively underexplored. Particularly overlooked in biodiversity assessments are small species, such as protists, fungi, and many small invertebrates that are collectively known as meiofauna. These ...
    • Morphology, Transcriptomics and In Vitro Model of Skin from Polar Cod (Boreogadus Saida) and Atlantic Cod (Gadus Morhua) 

      Ytteborg, Elisabeth; Hansen, Øyvind Johannes; Høst, Vibeke; Afanasyev, Sergey; Vieweg, Ireen; Nahrgang, Jasmine; Krasnov, Aleksei (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-04)
      Fish skin is a multifunctional barrier tissue with high regeneration capacity that interacts with the surrounding environment and provides protection. Functional importance, high complexity and activity make skin an attractive tissue for studying the effects of environmental challenges and chemical stressors in fish. The aim of this work was to characterize skin from polar cod (<i>Boreogadus saida</i>) ...
    • Resource‐driven colonization by cod in a high Arctic food web 

      Johannesen, Edda; Yoccoz, Nigel; Tveraa, Torkild; Schackell, Nancy L.; Ellingsen, Kari; Dolgov, Andrey V.; Frank, Kenneth T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-23)
      <ol> <li>Climate change is commonly associated with many species redistributions and the influence of other factors may be marginalized, especially in the rapidly warming Arctic.</li> <li>The Barents Sea, a high latitude large marine ecosystem in the Northeast Atlantic has experienced above‐average temperatures since the mid‐2000s with divergent bottom temperature trends at subregional ...
    • Assessing the responses of Sphagnum micro-eukaryotes to climate changes using high throughput sequencing 

      Reczuga, Monika Katarzyna; Seppey, Victor William Christophe; Mulot, Matthieu; Jassey, Vincent E.J.; Buttler, Alexandre; Slowinska, Sandra; Slowinski, Michal; Lara, Enrique; Lamentowicz, Mariusz; Mitchell, Edward A.D. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-18)
      Current projections suggest that climate warming will be accompanied by more frequent and severe drought events. Peatlands store ca. one third of the world’s soil organic carbon. Warming and drought may cause peatlands to become carbon sources through stimulation of microbial activity increasing ecosystem respiration, with positive feedback effect on global warming. Micro-eukaryotes play a key role ...
    • The Chloroplast Ribonucleoprotein CP33B Quantitatively Binds the psbA mRNA 

      Teubner, Marlene; Lenzen, Benjamin; Espenberger, Lucas Bernal; Fuss, Janina; Nickelsen, Jörg; Krause, Kirsten; Ruwe, Hannes; Schmitz-Linneweber, Christian (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-17)
      Chloroplast RNAs are stabilized and processed by a multitude of nuclear-encoded RNA-binding proteins, often in response to external stimuli like light and temperature. A particularly interesting RNA-based regulation occurs with the <i>psbA</i> mRNA, which shows light-dependent translation. Recently, the chloroplast ribonucleoprotein CP33B was identified as a ligand of the <i>psbA</i> mRNA. We here ...
    • Latitudinal Cline in Chromosome Numbers of Ice Cod A. glacialis (Gadidae) from Northeast Greenland 

      Ghigliotti, Laura; Christiansen, Jørgen Schou; Carlig, Erica; Di Blasi, D; Pisano, Eva (Journal article; Tidsskriftartikkel, 2020-12-18)
      The ice cod <i>Arctogadus glacialis</i> (Peters, 1872) is one of the few fish species endemic to the Arctic. With a circumpolar distribution, the species is confined to the fjords and shelves of the Arctic seas. Biological information on <i>A. glacialis</i> is scarce, with genomic information restricted to microsatellites. Within the frame of the TUNU-Programme: Arctic Ocean Fishes—Diversity, ...
    • Benthic scavenger community composition and carrion removal in Arctic and Subarctic fjords 

      Dunlop, Katherine Mary; Renaud, Paul Eric; Berge, Jørgen; Jones, Daniel O.B.; Harbour, Rob P.; Tandberg, Anne Helene S.; Sweetman, Andrew K. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-05)
      In high latitude coastal regions, benthic scavenger communities are largely composed of invertebrates that play a key role in the cycling of organic matter. Factors including temperature and depth can structure Arctic and Subarctic fjord benthic communities, but the response of scavenging communities to these factors is poorly known. To address this, we compared scavenging fauna in eight fjords with ...
    • Mitogenomics and the genetic differentiation of contemporary Balaena mysticetus (Cetacea) from Svalbard 

      Bachmann, Lutz; Cabrera, Andrea A.; Heide-Jørgensen, Mads-Peter; Shpak, Olga V.; Lydersen, Christian; Wiig, Øystein; Kovacs, Kit M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-12)
      Full mitochondrial genomes were assembled for 12 recently sampled animals from the Svalbard bowhead whale (Balaena mysticetus) stock via high-throughput sequencing data, facilitating analysis of the demographic history of the population for the first time. The Svalbard population has retained noticeable amounts of mitochondrial genome diversity despite extreme historical harvest levels. Haplotype ...
    • Modelling the effect of mesh size and opening angle on size selection and capture pattern in a snow crab (Chionoecetes opilio) pot fishery 

      Herrmann, Bent; Grimaldo, Eduardo; Brcic, Jure; Cerbule, Kristine (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-18)
      Size selection in commercial snow crab (Chionoecetes opilio) pot fisheries is important for reducing on-board sorting and unintended mortality of undersized individuals. In this paper, we tested whether snow crab of various sizes geometrically could pass through diamond meshes of different sizes and opening angles, to estimate a model for predicting the effect of mesh size and mesh opening angle on ...
    • The tomato receptor CuRe1 senses a cell wall protein to identify Cuscuta as a pathogen 

      Hegenauer, Volker; Slaby, Peter; Körner, Max; Bruckmüller, Julien-Alexander; Burggraf, Ronja; Albert, Isabell; Kaiser, Bettina; Löffelhardt, Birgit; Droste-Borel, Irina; Sklenar, Jan; Menke, Frank L. H.; Macek, Boris; Ranjan, Aashish; Sinha, Neelima; Nurnberger, Thorsten; Felix, Georg; Krause, Kirsten; Stahl, Mark; Albert, Markus (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-20)
      Parasitic plants of the genus Cuscuta penetrate shoots of host plants with haustoria and build a connection to the host vasculature to exhaust water, solutes and carbohydrates. Such infections usually stay unrecognized by the host and lead to harmful host plant damage. Here, we show a molecular mechanism of how plants can sense parasitic Cuscuta. We isolated an 11 kDa protein of the parasite cell ...
    • Connecting the data landscape of long‐term ecological studies: The SPI‐Birds data hub 

      Culina, Antica; Adriaensen, Frank; Bailey, Liam D.; Burgess, Malcolm; Charmantier, Anne; Cole, Ella F; Eeva, Tapio; Matthysen, Erik; Nater, Chloe Rebecca; Sheldon, Ben C.; Sæther, Bernt-Erik; Vriend, Stefan J.G.; Zajkova, Zuzana; Adamik, Peter; Aplin, Lucy M.; Angulo, Elena; Artemyev, Alexandr; Barba, Emilio; Barišić, Sanja; Belda, Eduardo; Bilgin, Cemal Can; Bleu, Josefa; Both, Christiaan; Bouwhuis, Sandra; Branston, Claire J.; Broggi, Juli; Burke, Terry; Bushuev, Andrey; Camacho, Carlos; Campobello, Daniela; Canal, David; Cantarero, Alejandro; Caro, Samuel P.; Chaine, Alexis; Cauchoix, Maxime; Cichoń, Mariusz; Ćiković, Davor; Cusimano, Camillo A.; Deimel, Caroline; Dhondt, André A.; Dingemanse, Niels J.; Doligez, Blandine; Doutrelant, Claire; Drobniak, Szymon M.; Dubiec, Anna; Eens, Marcel; Erikstad, Kjell E; Espín, Silvia; Farine, Damien R.; Mennerat, Adele (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-17)
      <ol> <li>The integration and synthesis of the data in different areas of science is drastically slowed and hindered by a lack of standards and networking programmes. Long‐term studies of individually marked animals are not an exception. These studies are especially important as instrumental for understanding evolutionary and ecological processes in the wild. Furthermore, their number and global ...
    • A highly efficient protocol for transforming Cuscuta reflexa based on artificially induced infection sites 

      Lachner, Lena Anna-Maria; Galstyan, Levon; Krause, Kirsten (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-10)
      The parasitic plant genus <i>Cuscuta</i> is notoriously difficult to transform and to propagate or regenerate in vitro. With it being a substantial threat to many agroecosystems, techniques allowing functional analysis of gene products involved in host interaction and infection mechanisms are, however, in high demand. We set out to explore whether <i>Agrobacterium</i>‐mediated transformation of ...
    • En hjerne for hver sesong 

      Melum, Vebjørn Jacobsen (Chronicle; Kronikk, 2020-09-19)
      Livet for oss nordboere er ganske annerledes om sommeren enn om vinteren. Lyse solfylte netter, bar hud, sterke farger og utallige lukter. Det syder av liv. I disse dager begynner intensiteten å ebbe ut. Men likefult, det bugner av overskudd. Full-ladede kropper med nullstilte hjerner som er klar for å ta fatt på et nytt skoleår/semester. I skogen bogner det av sopp og bær, på fjellet lyser det ...
    • Photoperiodic induction without light-mediated circadian entrainment in a High Arctic resident bird 

      Appenroth, Daniel; Melum, Vebjørn Jacobsen; West, Alexander Christopher; Dardente, Hugues; Hazlerigg, David; Wagner, Gabriela (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-21)
      Organisms use changes in photoperiod to anticipate and exploit favourable conditions in a seasonal environment. While species living at temperate latitudes receive day length information as a year-round input, species living in the Arctic may spend as much as two-thirds of the year without experiencing dawn or dusk. This suggests that specialised mechanisms may be required to maintain seasonal ...
    • Report from a krill focused survey with RV Kronprins Haakon and land-based predator work in Antarctica during 2018/2019 

      Krafft, Bjørn Arne; Bakkeplass, Kjell Gunnar; Berge, Terje; Biuw, Martin; Erices, Julio Alberto; Jones, Elizabeth Marie; Knutsen, Tor; Kubilius, Rokas; Kvalsund, Merete; Lindstrøm, Ulf; Macaulay, Gavin; Renner, Angelika; Rey, Alina; Søiland, Henrik; Wienerroither, Rupert; Ahonen, Heidi; Goto, Jade; Hoem, Nils; Huerta, Magdelena; Höfer, Juan; Iden, Oda; Jouanneau, William; Kruger, Lucas; Liholt, Håvard; Lowther, Andy; Makhado, Azwianewi B.; Mestre, Mireia; Narvestad, Audun; Oosthuisen, Chris; Rodrigues, Jose Antonio Canseco; Øyerhamn, Rune (Research report; Forskningsrapport, 2019)
      The primary objective for this krill research activity was twofold 1) to conduct a survey that provides updated estimates of the biomass and distribution of krill which are used in models to estimate sustainable yield in CCAMLR Area 48 and 2) to develop knowledge on the marine environment essential for the implementation of a Feed-Back Management (FBM) system. The survey follows a similar design ...
    • Environmental conditions alter successional trajectories on an ephemeral resource: a field experiment with beetles in dead wood 

      Vindstad, Ole Petter Laksforsmo; Birkemoe, Tone; Ims, Rolf Anker; Sverdrup-Thygeson, Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-07)
      Successional processes can be observed for many organisms and resources, but most studies of succession have focused on plants. A general framework has been proposed, advocating that successional patterns in species turnover are predominantly driven by competition, dispersal or abiotic limitation, and that the patterning of species accumulation over time gives clues to which process is most influential ...
    • A Polar Surface Eddy Obscured by Thermal Stratification 

      Porter, Marie; Henley, Sian F.; Orkney, A.; Bouman, H. A.; Hwang, B.; Dumont, E.; Venables, E. J.; Cottier, Finlo Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-12)
      Mesoscale and submesoscale eddies play an important role in the distribution of heat and biogeochemical properties throughout the global oceans. Such eddies are important in the Arctic Ocean, particularly in the frontal regions, but are difficult to detect using traditional satellite‐based methods. Here we use high‐resolution in situ data from an underwater glider to identify a surface eddy that was ...